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Sample records for abrasion-resistant thin films

  1. Development and Testing of Abrasion Resistant Hard Coats For Polymer Film Reflectors: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jorgensen, G.; Gee, R.; DiGrazia, M.

    2010-10-01

    Reflective polymer film technology can significantly reduce the cost of solar reflectors and installed Concentrated Solar Power (CSP) plants by both reduced material cost and lower weight. One challenge of polymer reflectors in the CSP environment pertains to contact cleaning methods typically used with glass mirrors. Such contact cleaning methods can scratch the surface of polymer reflectors and thereby reduce specular reflectance. ReflecTech, Inc. (a subsidiary of SkyFuel, Inc.) and the National Renewable Energy Laboratory (NREL) initiated a cooperative research and development agreement (CRADA) to devise and develop an abrasion resistant coating (ARC) suitable for deposition onto polymer based mirror film. A number of candidate ARC products were identified as candidate formulations. Industrial collaborators prepared samples having their ARCs deposited onto ReflecTech Mirror Film pre-laminated to aluminum sheet substrates. Samples were provided for evaluation and subjected to baseline (unweathered) and accelerated exposure conditions and subsequently characterized for abrasion resistance and adhesion. An advanced ARC product has been identified that exhibits outstanding initial abrasion resistance and adhesion to ReflecTech Mirror Film. These properties were also retained after exposure to the various accelerated stress conditions. This material has been successfully manufactured as a 1.5 m wide roll-to-roll construction in a production environment.

  2. Photochemical surface modification of PP for abrasion resistance

    International Nuclear Information System (INIS)

    Bahners, Thomas; Haessler, Ruediger; Gao Shanglin; Maeder, Edith; Wego, Andreas; Schollmeyer, Eckhard

    2009-01-01

    The potential of a photo-chemical approach to increase the surface hardness of polypropylene (PP) has been studied. Using a 222 nm excimer lamp, fibers and film were irradiated in the presence of multi-functional substances diallylphthalate (DAP), tetraallyloxyethane (TAE), and pentaerithritoltriacylate (PETA) and characterized with regard to the resulting effect on abrasion resistance. AFM-based methods were employed to analyze thermo-mechanical surface properties. Nanoindentation and microthermal analyses of the outermost surface layers of UV treated fibers gave clear indications of an effective cross-linking of reactive substances present during irradiation. One may assume that the reactive media polymerize on top of the surface of the PP substrate and form a thin-layer. The abrasion resistance of the PP fibers was tested by applying stress through a rotating and axially oscillating roller of defined roughness and measuring the mass loss as a function of time. The abrasion resistance was found to be remarkably improved compared to the untreated fiber. Best effects were achieved using PETA as reactive substance. The experiments clearly showed the influence of processing conditions, namely with regard to homogeneous coverage of the substrate surface with the reactive medium.

  3. Resistivity of thiol-modified gold thin films

    International Nuclear Information System (INIS)

    Correa-Puerta, Jonathan; Del Campo, Valeria; Henríquez, Ricardo; Häberle, Patricio

    2014-01-01

    In this work, we study the effect of thiol self assembled monolayers on the electrical resistivity of metallic thin films. The analysis is based on the Fuchs–Sondheimer–Lucas theory and on electrical transport measurements. We determined resistivity change due to dodecanethiol adsorption on gold thin films. For this purpose, we controlled the deposition and annealing temperatures of the films to change the surface topography and to diminish the effect of electron grain boundary scattering. Results show that the electrical response to the absorption of thiols strongly depends on the initial topography of the surface. - Highlights: • We study the effect of self assembled monolayers on the resistivity of thin films. • Fuchs–Sondheimer theory reproduces the resistivity increase due to thiol deposition. • We determined resistivity change due to dodecanethiol deposition on gold thin films. • The electrical response strongly depends on the substrate surface topography

  4. Resistivity of thiol-modified gold thin films

    Energy Technology Data Exchange (ETDEWEB)

    Correa-Puerta, Jonathan [Instituto de Física, Pontificia Universidad Católica de Valparaíso, Av. Universidad 330, Curauma, Valparaíso (Chile); Del Campo, Valeria [Departamento de Física, Universidad Técnica Federico Santa María, Av. España 1680, Valparaiso 2390123 (Chile); Henríquez, Ricardo, E-mail: ricardo.henriquez@usm.cl [Departamento de Física, Universidad Técnica Federico Santa María, Av. España 1680, Valparaiso 2390123 (Chile); Häberle, Patricio [Departamento de Física, Universidad Técnica Federico Santa María, Av. España 1680, Valparaiso 2390123 (Chile)

    2014-11-03

    In this work, we study the effect of thiol self assembled monolayers on the electrical resistivity of metallic thin films. The analysis is based on the Fuchs–Sondheimer–Lucas theory and on electrical transport measurements. We determined resistivity change due to dodecanethiol adsorption on gold thin films. For this purpose, we controlled the deposition and annealing temperatures of the films to change the surface topography and to diminish the effect of electron grain boundary scattering. Results show that the electrical response to the absorption of thiols strongly depends on the initial topography of the surface. - Highlights: • We study the effect of self assembled monolayers on the resistivity of thin films. • Fuchs–Sondheimer theory reproduces the resistivity increase due to thiol deposition. • We determined resistivity change due to dodecanethiol deposition on gold thin films. • The electrical response strongly depends on the substrate surface topography.

  5. Thin Cu film resistivity using four probe techniques: Effect of film thickness and geometrical shapes

    Science.gov (United States)

    Choudhary, Sumita; Narula, Rahul; Gangopadhyay, Subhashis

    2018-05-01

    Precise measurement of electrical sheet resistance and resistivity of metallic thin Cu films may play a significant role in temperature sensing by means of resistivity changes which can further act as a safety measure of various electronic devices during their operation. Four point probes resistivity measurement is a useful approach as it successfully excludes the contact resistance between the probes and film surface of the sample. Although, the resistivity of bulk samples at a particular temperature mostly depends on its materialistic property, however, it may significantly differ in the case of thin films, where the shape and thickness of the sample can significantly influence on it. Depending on the ratio of the film thickness to probe spacing, samples are usually classified in two segments such as (i) thick films or (ii) thin films. Accordingly, the geometric correction factors G can be related to the sample resistivity r, which has been calculated here for thin Cu films of thickness up to few 100 nm. In this study, various rectangular shapes of thin Cu films have been used to determine the shape induced geometric correction factors G. An expressions for G have been obtained as a function of film thickness t versus the probe spacing s. Using these expressions, the correction factors have been plotted separately for each cases as a function of (a) film thickness for fixed linear probe spacing and (b) probe distance from the edge of the film surface for particular thickness. Finally, we compare the experimental results of thin Cu films of various rectangular geometries with the theoretical reported results.

  6. Characterization of interference thin films grown on stainless steel surface by alternate pulse current in a sulphochromic solution

    Directory of Open Access Journals (Sweden)

    Rosa Maria Rabelo Junqueira

    2008-12-01

    Full Text Available The aim of this work was to characterize thin interference films grown on the surface of AISI 304 stainless steel for decorative purposes. Films were grown in a sulphochromic solution at room temperature by an alternating pulse current method. The morphology and chemical state of the elements in the films were investigated by field emission scanning electron microscopy (FESEM, atomic force microscopy (AFM, glow discharge optical emission spectrometry (GDOES, and infrared Fourier transform spectroscopy (FTIR. Depth-sensing indentation (DSI experiments and wear abrasion tests were employed to assess the mechanical resistance of the films. The coloration process resulted in porous thin films which increased the surface roughness of the substrate. The interference films mainly consisted of hydrated chromium oxide containing iron. Increasing film thickness produced different colors and affected the mechanical properties of the coating-substrate system. Thicker films, such as those producing gold and green colors, were softer but more abrasion resistant.

  7. Nanotechnological Advances in Catalytic Thin Films for Green Large-Area Surfaces

    Directory of Open Access Journals (Sweden)

    Suzan Biran Ay

    2015-01-01

    Full Text Available Large-area catalytic thin films offer great potential for green technology applications in order to save energy, combat pollution, and reduce global warming. These films, either embedded with nanoparticles, shaped with nanostructuring techniques, hybridized with other systems, or functionalized with bionanotechnological methods, can include many different surface properties including photocatalytic, antifouling, abrasion resistant and mechanically resistive, self-cleaning, antibacterial, hydrophobic, and oleophobic features. Thus, surface functionalization with such advanced structuring methods is of significance to increase the performance and wide usage of large-area thin film coatings specifically for environmental remediation. In this review, we focus on methods to increase the efficiency of catalytic reactions in thin film and hence improve the performance in relevant applications while eliminating high cost with the purpose of widespread usage. However, we also include the most recent hybrid architectures, which have potential to make a transformational change in surface applications as soon as high quality and large area production techniques are available. Hence, we present and discuss research studies regarding both organic and inorganic methods that are used to structure thin films that have potential for large-area and eco-friendly coatings.

  8. Resistance switching induced by electric fields in manganite thin films

    International Nuclear Information System (INIS)

    Villafuerte, M; Juarez, G; Duhalde, S; Golmar, F; Degreef, C L; Heluani, S P

    2007-01-01

    In this work, we investigate the polarity-dependent Electric Pulses Induced Resistive (EPIR) switching phenomenon in thin films driven by electric pulses. Thin films of 0.5 Ca 0.5 MnO 3 (manganite) were deposited by PLD on Si substrate. The transport properties at the interface between the film and metallic electrode are characterized in order to study the resistance switching. Sample thermal treatment and electrical field history are important to be considered for get reproducible EPIR effect. Carriers trapping at the interfaces are considered as a possible explanation of our results

  9. Anti-abrasive nanocoatings current and future applications

    CERN Document Server

    2015-01-01

    This book provides an overview of the fabrication methods for anti-abrasive nanocoatings. The connections among fabrication parameters, the characteristics of nanocoatings and the resulting properties (i.e. nanohardness, toughness, wear rate, load-bearing ability, friction coefficient, and scratch resistance) are discussed. Size-affected mechanical properties of nanocoatings are examined, including their uses. Anti-abrasive nanocoatings, including metallic-, ceramic-, and polymeric-based layers, as well as different kinds of nanostructures, such as multi-layered nanocomposites and thin films, are reviewed. * Provides a comprehensive overview of the fabrication methods for anti-abrasive nanocoatings* Discusses the connections among fabrication parameters, the characteristics of nanocoatings and the resulting properties* Reviews advantages and drawbacks of fabrication methods for anti-abrasive nanocoatings and clarifies the place of these nanocoatings in the world of nanotechnology

  10. Investigation of resistive switching in barium strontium titanate thin films for memory applications

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Wan

    2010-11-17

    Resistive random access memory (RRAM) has attracted much attention due to its low power consumption, high speed operation, non-readout disturbance and high density integration potential and is regarded as one of the most promising candidates for the next generation non-volatile memory. The resistive switching behavior of Mn-doped BaSrTiO{sub 3} (BST) thin films with different crystalline properties was investigated within this dissertation. The laser fluence dependence was checked in order to optimize the RRAM properties. Although the film epitaxial quality was improved by reducing the laser energy during deposition process, the yields fluctuated and only 3% RRAM devices with highest epitaxial quality of BST film shows resistive switching behavior instead of 67% for the samples with worse film quality. It gives a clue that the best thin film quality does not result in the best switching performance, and it is a clear evidence of the importance of the defects to obtain resistive switching phenomena. The bipolar resistive switching behavior was studied with epitaxial BST thin films on SRO/STO. Compared to Pt top electrode, the yield, endurance and reliability were strongly improved for the samples with W top electrode. Whereas the samples with Pt top electrode show a fast drop of the resistance for both high and low resistance states, the devices with W top electrode can be switched for 10{sup 4} times without any obvious degradation. The resistance degradation for devices with Pt top electrode may result from the diffusion of oxygen along the Pt grain boundaries during cycling whereas for W top electrode the reversible oxidation and reduction of a WO{sub x} layer, present at the interface between W top electrode and BST film, attributes to the improved switching property. The transition from bipolar to unipolar resistive switching in polycrystalline BST thin films was observed. A forming process which induces a metallic low resistance state is prerequisite for the

  11. Investigation of resistive switching in barium strontium titanate thin films for memory applications

    International Nuclear Information System (INIS)

    Shen, Wan

    2010-01-01

    Resistive random access memory (RRAM) has attracted much attention due to its low power consumption, high speed operation, non-readout disturbance and high density integration potential and is regarded as one of the most promising candidates for the next generation non-volatile memory. The resistive switching behavior of Mn-doped BaSrTiO 3 (BST) thin films with different crystalline properties was investigated within this dissertation. The laser fluence dependence was checked in order to optimize the RRAM properties. Although the film epitaxial quality was improved by reducing the laser energy during deposition process, the yields fluctuated and only 3% RRAM devices with highest epitaxial quality of BST film shows resistive switching behavior instead of 67% for the samples with worse film quality. It gives a clue that the best thin film quality does not result in the best switching performance, and it is a clear evidence of the importance of the defects to obtain resistive switching phenomena. The bipolar resistive switching behavior was studied with epitaxial BST thin films on SRO/STO. Compared to Pt top electrode, the yield, endurance and reliability were strongly improved for the samples with W top electrode. Whereas the samples with Pt top electrode show a fast drop of the resistance for both high and low resistance states, the devices with W top electrode can be switched for 10 4 times without any obvious degradation. The resistance degradation for devices with Pt top electrode may result from the diffusion of oxygen along the Pt grain boundaries during cycling whereas for W top electrode the reversible oxidation and reduction of a WO x layer, present at the interface between W top electrode and BST film, attributes to the improved switching property. The transition from bipolar to unipolar resistive switching in polycrystalline BST thin films was observed. A forming process which induces a metallic low resistance state is prerequisite for the observation of

  12. Electrical resistivity of thin metal films and multilayers

    International Nuclear Information System (INIS)

    Fenn, M.

    1999-01-01

    The electrical resistivity and temperature coefficient of resistivity (TCR) of thin films and multilayers of Cu, Nb and Zr have been measured over a wide range of layer thicknesses. The structure of the films has been characterised using transmission electron microscopy (TEM) and x-ray reflectivity. The experimental results have been compared with the semiclassical theory due to Dimmich. The values of the grain boundary reflectivity, R, in the single films has been found to be approximately 0.35 for Cu in agreement with the literature. The value of R for Nb and Zr has been found to vary with grain size, although it is approximately 0.55 for Nb and 0.925 for Zr over a wide range of grain sizes, and this is believed to be presented for the first time. The value of the interfacial specularity parameter, p, is not found to have a significant effect compared to R in the single films. Dimmich's theoretical expression for the TCR does not match experiment, but by adapting the resistivity expression of the theory to different temperatures a satisfactory fit has been obtained. It has been concluded that the assumption of the free electron model in the presence of grain boundary scattering is in error. The adapted theory predicts negative TCR in sufficiently thin films with experimentally plausible values of the input parameters, and this is believed to be demonstrated for the first time. The experimental resistivity of the multilayers was much lower than expected from the resistivity of the single films. A theoretical fit to the experimental resistivity and TCR of the multilayers was obtained by adjusting the parameter values obtained from single films, and the value of p was found to be significant. This procedure leads to a contradiction in the value of R for Nb. With a view to extending the above work to magnetic multilayers, an AC susceptometer has been designed, built and tested. The results indicate that this instrument would be suitable for work on magnetic

  13. Modification of UV absorption profile of polymer film reflectors to increase solar-weighted reflectance

    Science.gov (United States)

    Jorgensen, Gary; Gee, Randall C.; White, David

    2017-05-02

    Provided are reflective thin film constructions including a reduced number of layers, which provides for increased solar-weighted hemispherical reflectance and durability. Reflective films include those comprising an ultraviolet absorbing abrasion resistant coating over a metal layer. Also provided are ultraviolet absorbing abrasion resistant coatings and methods for optimizing the ultraviolet absorption of an abrasion resistant coating. Reflective films disclosed herein are useful for solar reflecting, solar collecting, and solar concentrating applications, such as for the generation of electrical power.

  14. Transforming Anaerobic Adhesives into Highly Durable and Abrasion Resistant Superhydrophobic Organoclay Nanocomposite Films: A New Hybrid Spray Adhesive for Tough Superhydrophobicity

    Science.gov (United States)

    Bayer, Ilker S.; Brown, Andrea; Steele, Adam; Loth, Eric

    2009-12-01

    The authors report fabrication of tough nanostructured self-cleaning superhydrophobic polymer-organoclay films from anaerobic acrylic adhesives displaying strong adhesion to metal surfaces. Both industrial and bio-grade anaerobic adhesives such as bone cements could be used. Montmorillonite clay filled anaerobic adhesives were modified by blending with a water dispersed fluoro-methacrylic latex in solution to form abrasion resistant interpenetrating polymer network films upon spray casting. The adhesive films could cure by thermosetting in oxygen-rich environments. Very high contact angles with low hysteresis were also measured for acidic (pH 2) and basic (pH 11) aqueous buffer solutions indicating resistance to acidic and basic media.

  15. Electrical resistivity measurements to predict abrasion resistance of ...

    Indian Academy of Sciences (India)

    WINTEC

    increasing expansion of highway and other construction works and decreasing natural aggregate resources in the world, the demand for crushed stone aggregates has in- creased from day-to-day. One of the important properties of rock aggregates is abrasion resistance. The abrasion resistance of aggregates is generally ...

  16. Usage of abrasion-resistant materials in agriculture

    Directory of Open Access Journals (Sweden)

    J Votava

    2014-06-01

    Full Text Available Agricultural soil-processing machines are subject to an extensive abrasive wear. This paper analyses technical materials and their fitness to exchangeable parts of plough bottoms, such as edge-tools and whole plough cutting edges. There were tested abrasion-resistant steels with different microstructures: austenite, martensite-bainite, and carbide. Steel with the pearlite-ferrite structure was used as an etalon. Abrasion resistance tests were processed in compliance with the norm CSN 01 5084, which is a test of abrasion wear on abrasive cloth.

  17. Resistivity behavior of optimized PbTiO3 thin films prepared by spin coating method

    Science.gov (United States)

    Nurbaya, Z.; Wahid, M. H.; Rozana, M. D.; Alrokayan, S. A. H.; Khan, H. A.; Rusop, M.

    2018-05-01

    Th is study presents the resistivity behavior of PbTiO3 thin films which were prepared towards metal-insulator-metal capacitor device fabrication. The PbTiO3 thin films were prepared through sol-gel spin coating method that involved various deposition parameters that is (1) different molar concentration of PbTiO3 solutions, (2) various additional PbAc-content in PbTiO3 solutions, and (3) various annealing temperature on PbTiO3 thin films. Hence, an electrical measurement of current versus voltage was done to determine the resistivity behavior of PbTiO3 thin films.

  18. Quantifying resistances across nanoscale low- and high-angle interspherulite boundaries in solution-processed organic semiconductor thin films.

    Science.gov (United States)

    Lee, Stephanie S; Mativetsky, Jeffrey M; Loth, Marsha A; Anthony, John E; Loo, Yueh-Lin

    2012-11-27

    The nanoscale boundaries formed when neighboring spherulites impinge in polycrystalline, solution-processed organic semiconductor thin films act as bottlenecks to charge transport, significantly reducing organic thin-film transistor mobility in devices comprising spherulitic thin films as the active layers. These interspherulite boundaries (ISBs) are structurally complex, with varying angles of molecular orientation mismatch along their lengths. We have successfully engineered exclusively low- and exclusively high-angle ISBs to elucidate how the angle of molecular orientation mismatch at ISBs affects their resistivities in triethylsilylethynyl anthradithiophene thin films. Conductive AFM and four-probe measurements reveal that current flow is unaffected by the presence of low-angle ISBs, whereas current flow is significantly disrupted across high-angle ISBs. In the latter case, we estimate the resistivity to be 22 MΩμm(2)/width of the ISB, only less than a quarter of the resistivity measured across low-angle grain boundaries in thermally evaporated sexithiophene thin films. This discrepancy in resistivities across ISBs in solution-processed organic semiconductor thin films and grain boundaries in thermally evaporated organic semiconductor thin films likely arises from inherent differences in the nature of film formation in the respective systems.

  19. Electrical resistivity of ferrimagnetic magnetite thin film

    International Nuclear Information System (INIS)

    Varshney, Dinesh; Yogi, A.; Kaurav, N.; Gupta, R.P.; Phase, D.M.

    2006-01-01

    We have grown Fe 3 O 4 (III) epitaxial film on Al 2 O 3 (0001) substrate by pulsed laser deposition, with thickness of 130 nm. X-ray diffraction studies of magnetite show the spinel cubic structure of film with preferential (III) orientation. The electrical resistivity measurement demonstrates that the properties of thin film of magnetite are basically similar to those of bulk magnetite and clearly shows semiconductor-insulator transition at Verwey transition temperature (≅140 K). We have found higher Verwey transition temperature when compared with earlier reports on similar type of system. Possible causes for increase in transition temperature are discussed. (author)

  20. Abnormal electrical resistivity in γ-TiAl thin films deposited by magnetron sputtering

    International Nuclear Information System (INIS)

    Alford, T.L.; Gadre, K.S.; Kim, H.C.; Deevi, S.C.

    2003-01-01

    Thin films of γ-TiAl are being considered as a potential conductor and/or diffusion barrier for high temperature electronics because of their high melting points and high oxidation resistance. However, it is not possible to form pure γ-TiAl thin films by thermal annealing of Al/Ti bilayers. This study, however, demonstrates the formation of γ-TiAl thin films by dc magnetron sputtering of a compound target. X-ray diffractometry and Rutherford backscattering spectrometry analyses confirm the γ-TiAl phase formation, composition, and thermal stability in vacuum (up to 700 deg. C, 1 h) on SiO 2 . Four-point probe resistivity measurements in vacuum show an initial increase in the resistivity with temperature up to transition temperature for the γ-TiAl thin films. At higher temperatures a decrease in resistivity with additional heating (i.e., negative temperature coefficient of resistivity, TCR) is seen. The values of dρ/dT are typically on the order of -0.32 μΩ cm/ deg. C between 200 and 550 deg. C. At the highest temperature, a minimum value of resistivity of ∼13 μΩ cm is obtained; this value is about one half the value of bulk TiAl at room temperatures. The negative TCR, low resistivity values at high temperatures, and temperature stability are not typically seen in bulk TiAl. This abnormal electrical property is explained using a modified model for a thermally activated polaron-hopping mechanism

  1. Chemically robust carbon nanotube–PTFE superhydrophobic thin films with enhanced ability of wear resistance

    Institute of Scientific and Technical Information of China (English)

    Kewei Wang; Pan Xiong; Xiuping Xu; Kan Wang; YanLong Li; Yufeng Zheng

    2017-01-01

    A chemically robust superhydrophobic nanocomposite thin film with enhanced wear resistance is prepared from a composite comprising polytetrafluoroethylene (PTFE) and carbon nanotubes. The superhydrophobic thin films with hierarchical structure are fabricated by spraying an environmentally friendly aqueous dispersion containing carbon nanotubes and PTFE resin on silicon wafer. Thin films with a contact angle of 154.1° ± 2° and a sliding angle less than 2° remain superhydrophobic after abrading over 500 times under a pressure of 50 g/cm2. The thin film is also extremely stable even under much stress conditions. To further the understanding of the enhancement of wear resistance, we investigated the formation of microsized structure and their effects. The growth of microbumps is caused by attracting solution droplet to the hydrophilic islands on hydrophobic surface.

  2. TiFeCoNi oxide thin film - A new composition with extremely low electrical resistivity at room temperature

    International Nuclear Information System (INIS)

    Yang, Ya-Chu; Tsau, Chun-Huei; Yeh, Jien-Wei

    2011-01-01

    We show the electrical resistivity of a TiFeCoNi oxide thin film. The electrical resistivity of the TiFeCoNi thin film decreased sharply after a suitable period of oxidation at high temperature. The lowest resistivity of the TiFeCoNi oxide film was 35 ± 3 μΩ-cm. The low electrical resistivity of the TiFeCoNi oxide thin film was attributed to Ti, which is more reactive than the other elements, reacting with oxygen at the initial stage of annealing. The low resistivity is caused by the remaining electrons.

  3. The ion plating of optical thin films for the infrared

    International Nuclear Information System (INIS)

    Reid, I.M.; Macleod, H.A.; Carter, M.J.; Henderson, E.

    1979-01-01

    Although excellent humidity resistance was achieved with diode ion plated zinc sulphide antireflection films on germanium substrates the abrasion resistance was found to be poor. This could be attributed to an intense columnar structure with very loose packing. To improve the abrasion resistance it was found necessary to add a third electrode which allowed the discharge to be sustained at lower pressures, and to heat the substrates during deposition. (author)

  4. Electrical resistivity of thin metal films

    CERN Document Server

    Wissmann, Peter

    2007-01-01

    The aim of the book is to give an actual survey on the resistivity of thin metal and semiconductor films interacting with gases. We discuss the influence of the substrate material and the annealing treatment of the films, presenting our experimental data as well as theoretical models to calculate the scattering cross section of the conduction electrons in the frame-work of the scattering hypothesis. Main emphasis is laid on the comparison of gold and silver films which exhibit nearly the same lattice structure but differ in their chemical activity. In conclusion, the most important quantity for the interpretation is the surface charging z while the correlation with the optical data or the frustrated IR vibrations seems the show a more material-specific character. Z can be calculated on the basis of the density functional formalism or the self-consistent field approximation using Mulliken’s population analysis.

  5. Electrical resistivity measurements to predict abrasion resistance

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 31; Issue 2. Electrical resistivity measurements to predict abrasion resistance of rock aggregates ... It was seen that correlation coefficients were increased for the rock classes. In addition ...

  6. Resistive switching in polycrystalline YMnO3 thin films

    Directory of Open Access Journals (Sweden)

    A. Bogusz

    2014-10-01

    Full Text Available We report a unipolar, nonvolatile resistive switching in polycrystalline YMnO3 thin films grown by pulsed laser deposition and sandwiched between Au top and Ti/Pt bottom electrodes. The ratio of the resistance in the OFF and ON state is larger than 103. The observed phenomena can be attributed to the formation and rupture of conductive filaments within the multiferroic YMnO3 film. The generation of conductive paths under applied electric field is discussed in terms of the presence of grain boundaries and charged domain walls inherently formed in hexagonal YMnO3. Our findings suggest that engineering of the ferroelectric domains might be a promising route for designing and fabrication of novel resistive switching devices.

  7. Preparation and properties of low resistivity molybdenum silicide thin films

    International Nuclear Information System (INIS)

    Beddies, G.; Hofmann, K.; Bretschneider, W.; Zscheile, H.D.; Bogdanowa, P.; Helms, H.; Wickleder, K.H.

    1983-01-01

    Using different sputtering methods and target variants Mo/Si mixed films are prepared. After the deposition these thin films are amorphous. Isothermal annealing in vacuum leads to the formation of crystalline phases. The crystallization of the hexagonal phase of MoSi 2 is connected with an increase in stress. The formation of the tetragonal phase causes a great decrease of the specific resistance

  8. Wear resistant PTFE thin film enabled by a polydopamine adhesive layer

    International Nuclear Information System (INIS)

    Beckford, Samuel; Zou, Min

    2014-01-01

    The influence of a polydopamine (PDA) adhesive layer on the friction and wear resistance of polytetrafluoroethylene (PTFE) thin films coated on stainless steel was investigated. The friction and wear tests were carried out using a ball on flat configuration under a normal load of 50 g, sliding speed of 2.5 mm/s, and stroke length of 15 mm. It is found that the PDA/PTFE film is able to withstand approximately 500 times more rubbing cycles than the PTFE film alone. X-ray photoelectron spectroscopy (XPS) results show that a tenacious layer of PTFE remains adhered to the PDA layer, which enables the durability of the PDA/PTFE film. Because of the relatively low thickness of the film, PDA/PTFE shows great potential for use in applications where durable, thin films are desirable

  9. Self-assembled thin film of imidazolium ionic liquid on a silicon surface: Low friction and remarkable wear-resistivity

    International Nuclear Information System (INIS)

    Gusain, Rashi; Kokufu, Sho; Bakshi, Paramjeet S.; Utsunomiya, Toru; Ichii, Takashi; Sugimura, Hiroyuki; Khatri, Om P.

    2016-01-01

    Graphical abstract: - Highlights: • Ionic liquid thin film is deposited on a silicon surface via covalent interaction. • Chemical and morphological features of ionic liquid thin film are probed by XPS and AFM. • Ionic liquid thin film exhibited low and steady friction along with remarkable wear-resistivity. - Abstract: Imidazolium-hexafluorophosphate (ImPF_6) ionic liquid thin film is prepared on a silicon surface using 3-chloropropyltrimethoxysilane as a bifunctional chemical linker. XPS result revealed the covalent grafting of ImPF_6 thin film on a silicon surface. The atomic force microscopic images demonstrated that the ImPF_6 thin film is composed of nanoscopic pads/clusters with height of 3–7 nm. Microtribological properties in terms of coefficient of friction and wear-resistivity are probed at the mean Hertzian contact pressure of 0.35–0.6 GPa under the rotational sliding contact. The ImPF_6 thin film exhibited low and steady coefficient of friction (μ = 0.11) along with remarkable wear-resistivity to protect the underlying silicon substrate. The low shear strength of ImPF_6 thin film, the covalent interaction between ImPF_6 ionic liquid thin film and underlying silicon substrate, and its regular grafting collectively reduced the friction and improved the anti-wear property. The covalently grafted ionic liquid thin film further shows immense potential to expand the durability and lifetime of M/NEMS based devices with significant reduction of the friction.

  10. Self-assembled thin film of imidazolium ionic liquid on a silicon surface: Low friction and remarkable wear-resistivity

    Energy Technology Data Exchange (ETDEWEB)

    Gusain, Rashi [CSIR-Indian Institute of Petroleum, Mohkampur, Dehardun 248005 (India); Academy of Scientific and Innovative Research, New Delhi 110025 (India); Kokufu, Sho [Department of Materials Science and Engineering, Kyoto University, Kyoto 606-8501 (Japan); Bakshi, Paramjeet S. [CSIR-Indian Institute of Petroleum, Mohkampur, Dehardun 248005 (India); Utsunomiya, Toru; Ichii, Takashi; Sugimura, Hiroyuki [Department of Materials Science and Engineering, Kyoto University, Kyoto 606-8501 (Japan); Khatri, Om P., E-mail: opkhatri@iip.res.in [CSIR-Indian Institute of Petroleum, Mohkampur, Dehardun 248005 (India); Academy of Scientific and Innovative Research, New Delhi 110025 (India)

    2016-02-28

    Graphical abstract: - Highlights: • Ionic liquid thin film is deposited on a silicon surface via covalent interaction. • Chemical and morphological features of ionic liquid thin film are probed by XPS and AFM. • Ionic liquid thin film exhibited low and steady friction along with remarkable wear-resistivity. - Abstract: Imidazolium-hexafluorophosphate (ImPF{sub 6}) ionic liquid thin film is prepared on a silicon surface using 3-chloropropyltrimethoxysilane as a bifunctional chemical linker. XPS result revealed the covalent grafting of ImPF{sub 6} thin film on a silicon surface. The atomic force microscopic images demonstrated that the ImPF{sub 6} thin film is composed of nanoscopic pads/clusters with height of 3–7 nm. Microtribological properties in terms of coefficient of friction and wear-resistivity are probed at the mean Hertzian contact pressure of 0.35–0.6 GPa under the rotational sliding contact. The ImPF{sub 6} thin film exhibited low and steady coefficient of friction (μ = 0.11) along with remarkable wear-resistivity to protect the underlying silicon substrate. The low shear strength of ImPF{sub 6} thin film, the covalent interaction between ImPF{sub 6} ionic liquid thin film and underlying silicon substrate, and its regular grafting collectively reduced the friction and improved the anti-wear property. The covalently grafted ionic liquid thin film further shows immense potential to expand the durability and lifetime of M/NEMS based devices with significant reduction of the friction.

  11. Deposition of Cu-doped PbS thin films with low resistivity using DC sputtering

    Directory of Open Access Journals (Sweden)

    Hariyadi Soetedjo

    2018-03-01

    Full Text Available Investigation of the electrical resistivity of Cu-doped PbS thin films has been carried out. The films were prepared using a DC sputtering technique. The doping was achieved by introducing the Cu dopant plate material directly on the surface of the PbS sputtering target plate. SEM-EDX data shows the Cu concentration in the PbS film to be proportional to the Cu plate diameter. The XRD pattern indicates the film is in crystalline cubic form. The Hall effect measurement shows that Cu doping yields an increase in the carrier concentration to 3.55 × 1019 cm−3 and a significant decrease in electrical resistivity. The lowest resistivity obtained was 0.13 Ωcm for a Cu concentration of 18.5%. Preferential orientation of (1 1 1 and (2 0 0 occurs during deposition. Keywords: Thin films, Lead sulfide, Sputtering, Resistivity, Semiconductor, Infrared

  12. Resistive switching properties and physical mechanism of europium oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Wei; Zou, Changwei [School of Physical Science and Technology, Lingnan Normal University, Zhanjiang (China); Bao, Dinghua [State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou (China)

    2017-09-15

    A forming-free resistive switching effect was obtained in Pt/Eu{sub 2}O{sub 3}/Pt devices in which the Eu{sub 2}O{sub 3} thin films were fabricated by a chemical solution deposition method. The devices show unipolar resistive switching with excellent switching parameters, such as high resistance ratio (10{sup 7}), stable resistance values (read at 0.2 V), low reset voltage, good endurance, and long retention time (up to 10{sup 4} s). On the basis of the analysis of the current-voltage (I-V) curves and the resistance-temperature dependence, it can be concluded that the dominant conducting mechanisms were ohmic behavior and Schottky emission at low resistance state and high resistance state, respectively. The resistive switching behavior could be explained by the formation and rupture of conductive filament, which is related to the abundant oxygen vacancies generated in the deposition process. This work demonstrates the great potential opportunities of Eu{sub 2}O{sub 3} thin film in resistive switching memory applications, which might possess distinguished properties. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Surface microstructures and corrosion resistance of Ni-Ti-Nb shape memory thin films

    Energy Technology Data Exchange (ETDEWEB)

    Li, Kun [School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Beijing Key Laboratory for Advanced Functional Materials and Thin Film Technology, Beihang University, Beijing 100191 (China); Faculty of Engineering and Environment, Northumbria University, Newcastle Upon Tyne NE1 8ST (United Kingdom); Li, Yan, E-mail: liyan@buaa.edu.cn [School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Beijing Key Laboratory for Advanced Functional Materials and Thin Film Technology, Beihang University, Beijing 100191 (China); Huang, Xu [Memry Corporation, Bethel, CT 06801 (United States); Gibson, Des [Institute of Thin Films, Sensors & Imaging, Scottish Universities Physics Alliance, University of the West of Scotland, Paisley PA1 2BE (United Kingdom); Zheng, Yang; Liu, Jiao; Sun, Lu [School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Beijing Key Laboratory for Advanced Functional Materials and Thin Film Technology, Beihang University, Beijing 100191 (China); Fu, Yong Qing, E-mail: richard.fu@northumbria.ac.uk [Faculty of Engineering and Environment, Northumbria University, Newcastle Upon Tyne NE1 8ST (United Kingdom)

    2017-08-31

    Highlights: • The corrosion resistance of Ni-Ti-Nb shape memory thin films is investigated. • Modified surface oxide layers improve the corrosion resistance of Ni-Ti-Nb films. • Further Nb additions reduce the potential corrosion tendency of the films. - Abstract: Ni-Ti-Nb and Ni-Ti shape memory thin films were sputter-deposited onto silicon substrates and annealed at 600 °C for crystallization. X-ray diffraction (XRD) measurements indicated that all of the annealed Ni-Ti-Nb films were composed of crystalline Ni-Ti (Nb) and Nb-rich grains. X-ray photoelectron spectroscopy (XPS) tests showed that the surfaces of Ni-Ti-Nb films were covered with Ti oxides, NiO and Nb{sub 2}O{sub 5}. The corrosion resistance of the Ni-Ti-Nb films in 3.5 wt.% NaCl solution was investigated using electrochemical tests such as open-circuit potential (OCP) and potentio-dynamic polarization tests. Ni-Ti-Nb films showed higher OCPs, higher corrosion potentials (E{sub corr}) and lower corrosion current densities (i{sub corr}) than the binary Ni-Ti film, which indicated a better corrosion resistance. The reason may be that Nb additions modified the passive layer on the film surface. The OCPs of Ni-Ti-Nb films increased with further Nb additions, whereas no apparent difference of E{sub corr} and i{sub corr} was found among the Ni-Ti-Nb films.

  14. Studies on nonvolatile resistance memory switching in ZnO thin films

    Indian Academy of Sciences (India)

    Six decades of research on ZnO has recently sprouted a new branch in the domain of resistive random access memories. Highly resistive and c-axis oriented ZnO thin films were grown by us using d.c. discharge assisted pulsed laser deposition on Pt/Ti/SiO2/Si substrates at room temperature. The resistive switching ...

  15. Control of electrical resistivity of TaN thin films by reactive sputtering for embedded passive resistors

    International Nuclear Information System (INIS)

    Kang, S.M.; Yoon, S.G.; Suh, S.J.; Yoon, D.H.

    2008-01-01

    Tantalum nitride thin films were deposited by radio frequency (RF) reactive sputtering at various N 2 /Ar gas flow ratios and working pressures to examine the change of their electrical resistivity. From the X-ray diffraction (XRD) and four-point probe sheet resistance measurements of the TaN x films, it was found that the change of the crystalline structures of the TaN x films as a function of the N 2 partial pressure caused an abrupt change of the electrical resistivity. When the hexagonal structure TaN thin films changed to an f.c.c. structure, the sheet resistance increased from 16 Ω/sq to 1396 Ω/sq. However, we were able to control the electrical resistivity of the TaN thin film in the range from 69 Ω/sq to 875 Ω/sq, with no change in crystalline structure, within a certain range of working pressures. The size of the grains in the scanning electron microscopy (SEM) images seemed to decrease with the increase of working pressure

  16. Effects of crystallographic texture on stress-migration resistance in copper thin films

    International Nuclear Information System (INIS)

    Koike, J.; Wada, M.; Sanada, M.; Maruyama, K.

    2002-01-01

    The crystallographic texture of heat-treated Cu thin films and its effects on stress-migration resistance were studied as a function of film thickness within a range of 50-900 nm. All as-deposited films had (111) texture. After heat treatment at 723 K, texture transition from (111) to (100) was observed in films of thickness greater than 300 nm. The (111) texture films after heat treatment showed severe stress migration; in contrast, the (100) texture films showed no noticeable stress migration. The observed stress-migration resistance in the (100) texture films can be attributed to the absence of twins and to lower thermal stress as compared with the (111) texture films

  17. The Microstructures and Electrical Resistivity of (Al, Cr, TiFeCoNiOx High-Entropy Alloy Oxide Thin Films

    Directory of Open Access Journals (Sweden)

    Chun-Huei Tsau

    2015-01-01

    Full Text Available The (Al, Cr, TiFeCoNi alloy thin films were deposited by PVD and using the equimolar targets with same compositions from the concept of high-entropy alloys. The thin films became metal oxide films after annealing at vacuum furnace for a period; and the resistivity of these thin films decreased sharply. After optimum annealing treatment, the lowest resistivity of the FeCoNiOx, CrFeCoNiOx, AlFeCoNiOx, and TiFeCoNiOx films was 22, 42, 18, and 35 μΩ-cm, respectively. This value is close to that of most of the metallic alloys. This phenomenon was caused by delaminating of the alloy oxide thin films because the oxidation was from the surfaces of the thin films. The low resistivity of these oxide films was contributed to the nonfully oxidized elements in the bottom layers and also vanishing of the defects during annealing.

  18. Tailoring surface properties of ArF resists thin films with functionally graded materials (FGM)

    Science.gov (United States)

    Takemoto, Ichiki; Ando, Nobuo; Edamatsu, Kunishige; Fuji, Yusuke; Kuwana, Koji; Hashimoto, Kazuhiko; Funase, Junji; Yokoyama, Hiroyuki

    2007-03-01

    Our recent research effort has been focused on new top coating-free 193nm immersion resists with regard to leaching of the resist components and lithographic performance. We have examined methacrylate-based resins that control the surface properties of ArF resists thin films by surface segregation behavior. For a better understanding of the surface properties of thin films, we prepared the six resins (Resin 1-6) that have three types fluorine containing monomers, a new monomer (Monomer A), Monomer B and Monomer C, respectively. We blended the base polymer (Resin 0) with Resin (1-6), respectively. We evaluated contact angles, surface properties and lithographic performances of the polymer blend resists. The static and receding contact angles of the resist that contains Resin (1-6) are greater than that of the base polymer (Resin 0) resist. The chemical composition of the surface of blend polymers was investigated with X-ray photoelectron spectroscopy (XPS). It was shown that there was significant segregation of the fluorine containing resins to the surface of the blend films. We analyzed Quantitative Structure-Property Relationships (QSPR) between the surface properties and the chemical composition of the surface of polymer blend resists. The addition of 10 wt% of the polymer (Resin 1-6) to the base polymer (Resin 0) did not influence the lithographic performance. Consequently, the surface properties of resist thin films can be tailored by the appropriate choice of fluorine containing polymer blends.

  19. Structure and mechanical properties of silica doped zirconia thin films

    Energy Technology Data Exchange (ETDEWEB)

    Uhlmann, Ina, E-mail: uhlmann@ceramics.tu-darmstadt.de [Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt (Germany); Hawelka, Dominik [Fraunhofer Institute for Laser Technology ILT, 52074 Aachen (Germany); Hildebrandt, Erwin [Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt (Germany); Pradella, Jens [Merck KGaA Darmstadt, 64293 Darmstadt (Germany); Rödel, Jürgen [Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt (Germany)

    2013-01-01

    Sol–gel based wear resistant coatings are presented as an alternative to existing vapor deposition coatings. The films consist of zirconia which has been doped with 8 wt.% silica. Crack-free single as well as multilayer coatings with thicknesses of 80 and 150 nm, respectively, could be produced after sintering at 1000 °C. The evolution of layer thickness, optical, chemical and mechanical properties during film annealing was investigated by ellipsometry, scanning electron microscopy, thermal gravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, nanoindentation and micro-abrasion. Micro-abrasion has been established as an easy and powerful tool to achieve first comparative abrasion data which could be correlated to hardness, Young's modulus and structure of the films. Above 600 °C a tetragonal, oxide coating with a Young's modulus ranging from 80 to 90 GPa, a hardness from 7 to 8 GPa and an increased abrasion resistance was obtained. The film density reached 4.64 g/cm{sup 3} with the mean refractive index n{sub 550} {sub nm} lying between 1.88 and 1.93. - Highlights: ► Sol–gel zirconia–8 wt.% silica coatings with hardness up to 8 GPa achieved ► Layer thickness as compared by ellipsometry and scanning electron microscopy ► Crack-free multilayer coatings produced up to 150 nm.

  20. Cathodic arc sputtering of functional titanium oxide thin films, demonstrating resistive switching

    Energy Technology Data Exchange (ETDEWEB)

    Shvets, Petr, E-mail: pshvets@innopark.kantiana.ru; Maksimova, Ksenia; Demin, Maxim; Dikaya, Olga; Goikhman, Alexander

    2017-05-15

    The formation of thin films of the different stable and metastable titanium oxide phases is demonstrated by cathode arc sputtering of a titanium target in an oxygen atmosphere. We also show that sputtering of titanium in vacuum yields the formation of titanium silicides on the silicon substrate. The crystal structure of the produced samples was investigated using Raman spectroscopy and X-ray diffraction. We conclude that cathode arc sputtering is a flexible method suitable for producing the functional films for electronic applications. The functionality is verified by the memory effect demonstration, based on the resistive switching in the titanium oxide thin film structure.

  1. Corrosion resistance of sintered NdFeB coated with SiC/Al bilayer thin films by magnetron sputtering

    International Nuclear Information System (INIS)

    Huang, Yiqin; Li, Heqin; Zuo, Min; Tao, Lei; Wang, Wei; Zhang, Jing; Tang, Qiong; Bai, Peiwen

    2016-01-01

    The poor corrosion resistance of sintered NdFeB imposes a great challenge in industrial applications. In this work, the SiC/Al bilayer thin films with the thickness of 510 nm were deposited on sintered NdFeB by magnetron sputtering to improve the corrosion resistance. A 100 nm Al buffer film was used to reduce the internal stress between SiC and NdFeB and improve the surface roughness of the SiC thin film. The morphologies and structures of SiC/Al bilayer thin films and SiC monolayer film were investigated with FESEM, AFM and X-ray diffraction. The corrosion behaviors of sintered NdFeB coated with SiC monolayer film and SiC/Al bilayer thin films were analyzed by polarization curves. The magnetic properties were measured with an ultra-high coercivity permanent magnet pulse tester. The results show that the surface of SiC/Al bilayer thin films is more compact and uniform than that of SiC monolayer film. The corrosion current densities of SiC/Al bilayer films coated on NdFeB in acid, alkali and salt solutions are much lower than that of SiC monolayer film. The SiC/Al bilayer thin films have little influence to the magnetic properties of NdFeB. - Highlights: • The same thick Al, SiC and SiC/Al films are deposited on NdFeB by magnetron sputtering. • 510 nm SiC/Al bilayer films can improve the corrosion resistance of the NdFeB evidently. • Al buffer layer improves effectively the surface roughness of the SiC thin film. • SiC/Al bilayer films do not deteriorate the magnetic properties of NdFeB.

  2. Corrosion resistance of sintered NdFeB coated with SiC/Al bilayer thin films by magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yiqin [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Li, Heqin, E-mail: lhqjs@hfut.edu.cn [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Zuo, Min; Tao, Lei; Wang, Wei [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Zhang, Jing; Tang, Qiong [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); School of Electronic Science and Applied Physics, Hefei University of Technology, Hefei 230009 (China); Bai, Peiwen [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China)

    2016-07-01

    The poor corrosion resistance of sintered NdFeB imposes a great challenge in industrial applications. In this work, the SiC/Al bilayer thin films with the thickness of 510 nm were deposited on sintered NdFeB by magnetron sputtering to improve the corrosion resistance. A 100 nm Al buffer film was used to reduce the internal stress between SiC and NdFeB and improve the surface roughness of the SiC thin film. The morphologies and structures of SiC/Al bilayer thin films and SiC monolayer film were investigated with FESEM, AFM and X-ray diffraction. The corrosion behaviors of sintered NdFeB coated with SiC monolayer film and SiC/Al bilayer thin films were analyzed by polarization curves. The magnetic properties were measured with an ultra-high coercivity permanent magnet pulse tester. The results show that the surface of SiC/Al bilayer thin films is more compact and uniform than that of SiC monolayer film. The corrosion current densities of SiC/Al bilayer films coated on NdFeB in acid, alkali and salt solutions are much lower than that of SiC monolayer film. The SiC/Al bilayer thin films have little influence to the magnetic properties of NdFeB. - Highlights: • The same thick Al, SiC and SiC/Al films are deposited on NdFeB by magnetron sputtering. • 510 nm SiC/Al bilayer films can improve the corrosion resistance of the NdFeB evidently. • Al buffer layer improves effectively the surface roughness of the SiC thin film. • SiC/Al bilayer films do not deteriorate the magnetic properties of NdFeB.

  3. Exchange bias and bistable magneto-resistance states in amorphous TbFeCo thin films

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaopu, E-mail: xl6ba@virginia.edu; Ma, Chung T.; Poon, S. Joseph, E-mail: sjp9x@virginia.edu [Department of Physics, University of Virginia, Charlottesville, Virginia 22904 (United States); Lu, Jiwei [Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Devaraj, Arun [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States); Spurgeon, Steven R.; Comes, Ryan B. [Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352 (United States)

    2016-01-04

    Amorphous TbFeCo thin films sputter deposited at room temperature on thermally oxidized Si substrate are found to exhibit strong perpendicular magnetic anisotropy. Atom probe tomography, scanning transmission electron microscopy, and energy dispersive X-ray spectroscopy mapping have revealed two nanoscale amorphous phases with different Tb atomic percentages distributed within the amorphous film. Exchange bias accompanied by bistable magneto-resistance states has been uncovered near room temperature by magnetization and magneto-transport measurements. The exchange anisotropy originates from the exchange interaction between the ferrimagnetic and ferromagnetic components corresponding to the two amorphous phases. This study provides a platform for exchange bias and magneto-resistance switching using single-layer amorphous ferrimagnetic thin films that require no epitaxial growth.

  4. Resistance switching in epitaxial SrCoOx thin films

    Science.gov (United States)

    Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk; Kim, Yeon Soo; Park, Bae Ho; Jeong, Huiseong; Park, Ji-Yong; Cho, Myung Rae; Park, Yun Daniel; Choi, Woo Seok; Kim, Dong-Wook; Jin, Hyunwoo; Lee, Suyoun; Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong

    2014-08-01

    We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO3 (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO2.5) and conducting perovskite (SrCoO3-δ) depending on the oxygen content. The current-voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoOx thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO2.5.

  5. Resistance switching in epitaxial SrCoOx thin films

    International Nuclear Information System (INIS)

    Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk; Kim, Yeon Soo; Park, Bae Ho; Jeong, Huiseong; Park, Ji-Yong; Cho, Myung Rae; Park, Yun Daniel; Choi, Woo Seok; Kim, Dong-Wook; Jin, Hyunwoo; Lee, Suyoun; Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong

    2014-01-01

    We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO 3 (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO 2.5 ) and conducting perovskite (SrCoO 3−δ ) depending on the oxygen content. The current–voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoO x thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO 2.5

  6. On the difference between optically and electrically determined resistivity of ultra-thin titanium nitride films

    NARCIS (Netherlands)

    Van Hao, B.; Kovalgin, Alexeij Y.; Wolters, Robertus A.M.

    2013-01-01

    This work reports on the determination and comparison of the resistivity of ultra-thin atomic layer deposited titanium nitride films in the thickness range 0.65–20 nm using spectroscopic ellipsometry and electrical test structures. We found that for films thicker than 4 nm, the resistivity values

  7. Tungsten oxide thin films grown by thermal evaporation with high resistance to leaching

    Energy Technology Data Exchange (ETDEWEB)

    Correa, Diogo S. [Universidade Federal de Pelotas (UFPel), RS (Brazil). Centro de Ciencias Quimicas, Farmaceuticas e de Alimentos; Pazinato, Julia C.O.; Freitas, Mauricio A. de; Radtke, Claudio; Garcia, Irene T.S., E-mail: irene@iq.ufrgs.br [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Instituto de Quimica; Dorneles, Lucio S. [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Centro de Ciencias Naturais e Exatas

    2014-05-15

    Tungsten oxides show different stoichiometries, crystal lattices and morphologies. These characteristics are important mainly when they are used as photocatalysts. In this work tungsten oxide thin films were obtained by thermal evaporation on (100) silicon substrates covered with gold and heated at 350 and 600 °C, with different deposition times. The stoichiometry of the films, morphology, crystal structure and resistance to leaching were characterized through X-ray photoelectron spectroscopy, micro-Raman spectroscopy, scanning and transmission electron microscopy, X-ray diffractometry, Rutherford backscattering spectrometry and O{sup 16} (α,α')O{sup 16} resonant nuclear reaction. Films obtained at higher temperatures show well-defined spherical nanometric structure; they are composed of WO{sub 3.1} and the presence of hydrated tungsten oxide was also observed. The major crystal structure observed is the hexagonal. Thin films obtained through thermal evaporation present resistance to leaching in aqueous media and excellent performance as photocatalysts, evaluated through the degradation of the methyl orange dye. (author)

  8. Corrosion resistance of sintered NdFeB coated with SiC/Al bilayer thin films by magnetron sputtering

    Science.gov (United States)

    Huang, Yiqin; Li, Heqin; Zuo, Min; Tao, Lei; Wang, Wei; Zhang, Jing; Tang, Qiong; Bai, Peiwen

    2016-07-01

    The poor corrosion resistance of sintered NdFeB imposes a great challenge in industrial applications. In this work, the SiC/Al bilayer thin films with the thickness of 510 nm were deposited on sintered NdFeB by magnetron sputtering to improve the corrosion resistance. A 100 nm Al buffer film was used to reduce the internal stress between SiC and NdFeB and improve the surface roughness of the SiC thin film. The morphologies and structures of SiC/Al bilayer thin films and SiC monolayer film were investigated with FESEM, AFM and X-ray diffraction. The corrosion behaviors of sintered NdFeB coated with SiC monolayer film and SiC/Al bilayer thin films were analyzed by polarization curves. The magnetic properties were measured with an ultra-high coercivity permanent magnet pulse tester. The results show that the surface of SiC/Al bilayer thin films is more compact and uniform than that of SiC monolayer film. The corrosion current densities of SiC/Al bilayer films coated on NdFeB in acid, alkali and salt solutions are much lower than that of SiC monolayer film. The SiC/Al bilayer thin films have little influence to the magnetic properties of NdFeB.

  9. Beryllium thin films for resistor applications

    Science.gov (United States)

    Fiet, O.

    1972-01-01

    Beryllium thin films have a protective oxidation resistant property at high temperature and high recrystallization temperature. However, the experimental film has very low temperature coefficient of resistance.

  10. Solidification structure and abrasion resistance of high chromium white irons

    Science.gov (United States)

    Doğan, Ö. N.; Hawk, J. A.; Laird, G.

    1997-06-01

    Superior abrasive wear resistance, combined with relatively low production costs, makes high Cr white cast irons (WCIs) particularly attractive for applications in the grinding, milling, and pumping apparatus used to process hard materials. Hypoeutectic, eutectic, and hypereutectic cast iron compositions, containing either 15 or 26 wt pct chromium, were studied with respect to the macrostructural transitions of the castings, solidification paths, and resulting microstructures when poured with varying superheats. Completely equiaxed macrostructures were produced in thick section castings with slightly hypereutectic compositions. High-stress abrasive wear tests were then performed on the various alloys to examine the influence of both macrostructure and microstructure on wear resistance. Results indicated that the alloys with a primarily austenitic matrix had a higher abrasion resistance than similar alloys with a pearlitic/bainitic matrix. Improvement in abrasion resistance was partially attributed to the ability of the austenite to transform to martensite at the wear surface during the abrasion process.

  11. Tribological improvement of moving microparts by application of thin films and micropatterning

    International Nuclear Information System (INIS)

    Bandorf, R; Paulkowski, D M; Schiffmann, K I; Kuester, R L A

    2008-01-01

    The relevance of active microsystems continually increases and with the expansion of applications also aspects of reliability and durability of the moving microparts. In particular, the microtribological improvement of active MEMS therefore was investigated and improved. On the one hand, the influence of different thin films was investigated; on the other hand, improvement by micropatterning of the tribological surfaces in combination with coatings was studied. Most promising results were gained using thin carbon-based films. The typical film thickness of the coatings was in a range of several tens up to a few hundred nanometres. The films were deposited by plasma processes varying different process parameters, mainly the applied bias voltage. Different doping elements (Si, Au and W) were added to the diamond-like carbon (DLC) films (a-C, a-C:H, a-C:H:Si, a-C:H:Au, and a-C:H:W). Different methods were used for characterizing the thin films. Under single asperity contact indentation and scratch tests were performed to determine microhardness, microwear and microfriction. An influence of the applied bias voltage on the micromechanical and microtribological properties was found. At low constant loads of 100 μN the more brittle a-C films showed an initially higher microwear volume than the more elastic a-C:H films. With increasing load the microwear of the a-C films showed less increase of microwear compared to a-C:H films. At low load in the range from 50 μN to a few 100 μN the friction coefficient in single-asperity contact decreased with increasing load. Reaching a critical load the behaviour changed and due to inelastic effects, the friction coefficient increased with further increasing load. For investigation of microabrasive wear under multi-asperity contact a specifically developed tester was used. Besides a ranking of different materials regarding their abrasive microwear resistance the influence of the substrate material on the resulting wear behaviour was

  12. Effect of substrate properties and thermal annealing on the resistivity of molybdenum thin films

    International Nuclear Information System (INIS)

    Schmid, U.; Seidel, H.

    2005-01-01

    In this study, the influence of substrate properties (e.g. roughness characteristics and chemical composition) on the electrical resistivity of evaporated molybdenum thin films is investigated as a function of varying parameters, such as film thickness (25-115 nm) and post-deposition annealing with temperatures up to T PDA = 900 deg. C. A thermally oxidized silicon wafer with very low surface roughness was used as one substrate type. In contrast, a low temperature co-fired ceramics substrate with a glass encapsulant printed in thick film technology is the representative for rough surface morphology. The electrical resistivity follows the prediction of the size effect up to T PDA = 600 deg. C independent of substrate nature. On the silicon-based substrate, the thickness-independent portion of the film resistivity ρ g in the 'as deposited' state is about 29 times higher than the corresponding bulk value for a mono-crystalline sample. Thin films of this refractory metal on the SiO 2 /Si substrate exhibit an average grain size of 4.9 nm and a negative temperature coefficient of resistivity (TCR). On the glass/ceramic-based substrate, however, ρ g is half the value as compared to that obtained on the SiO 2 /Si substrate and the TCR is positive

  13. The anomalous low temperature resistivity of thermally evaporated α-Mn thin film

    International Nuclear Information System (INIS)

    Ampong, F.K.; Boakye, F.; Nkum, R.K.

    2010-01-01

    Electrical resistivity measurements have been carried out on thermally evaporated α-Mn thin film between 300 and 1.4 K using the van der Pauw four probe technique. The film was grown on a glass substrate held at a temperature of 373 K, in an ambient pressure of 5x10 -6 Torr. The results show a resistance minimum, a notable characteristic of α-Mn but at a (rather high) temperature of 194±1 K. Below the resistivity maximum which corresponds to 70 K, the resistivity drops by only 0.02 μΩm indicating a rather short range magnetic ordering. The low temperature results show a tendency towards saturation of the resistivity as the temperature approaches zero suggesting a Kondo scattering.

  14. The anomalous low temperature resistivity of thermally evaporated alpha-Mn thin film

    Energy Technology Data Exchange (ETDEWEB)

    Ampong, F.K., E-mail: kampxx@yahoo.co [Department of Physics, Kwame Nkrumah University of Science and Technology, Kumasi (Ghana); Boakye, F.; Nkum, R.K. [Department of Physics, Kwame Nkrumah University of Science and Technology, Kumasi (Ghana)

    2010-08-15

    Electrical resistivity measurements have been carried out on thermally evaporated alpha-Mn thin film between 300 and 1.4 K using the van der Pauw four probe technique. The film was grown on a glass substrate held at a temperature of 373 K, in an ambient pressure of 5x10{sup -6} Torr. The results show a resistance minimum, a notable characteristic of alpha-Mn but at a (rather high) temperature of 194+-1 K. Below the resistivity maximum which corresponds to 70 K, the resistivity drops by only 0.02 muOMEGAm indicating a rather short range magnetic ordering. The low temperature results show a tendency towards saturation of the resistivity as the temperature approaches zero suggesting a Kondo scattering.

  15. Use of a Fabry-Perot resonator at millimeter wave frequencies in the determination of thin-film resistivities

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, S. J.

    1979-08-01

    A novel contact-free method of measuring resistivity of thin semiconducting films on highly conductive substrates is described. The material structure studied is commonly encountered in thin-film solar cell development. The microwave technique that involves using a semiconfocal Fabry-Perot cavity at a wavelength of 3 mm is discussed in detail. The sample consists o a thin film of CdS on a brass substrate and is mounted on the flat reflector of the cavity. Using field perturbation methods, an expression is derived that relates the film resistivity to the cavity quality factor Q. The cavity quality factor is an easily measured parameter and, by comparing measurements of Q with and without the sample mounted, an accurate measure of the resistivity is obtained. Accuracy of measurements and necessary sample constraints are discussed in detail. Three samples of CdS were measured on brass substrates spanning an order of magnitude in resistivity difference. The results of the method described agree with those of another method that involves current voltage measurement after application of a metallic contact. Unlike the latter method, however, the new technique provides a nondestructive way of measuring the resistivity of semiconductor films on conducting substrates and is amenable to automation.

  16. Inhibitory Effect Evaluation of Glycerol-Iron Oxide Thin Films on Methicillin-Resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    C. L. Popa

    2015-01-01

    Full Text Available The main purpose of this study was to evaluate the inhibitory effect of glycerol- iron oxide thin films on Methicillin-Resistant Staphylococcus aureus (MRSA. Our results suggest that glycerol-iron oxide thin films could be used in the future for various biomedical and pharmaceutical applications. The glycerol-iron oxide thin films have been deposited by spin coating method on a silicon (111 substrate. The structural properties have been studied by X-ray diffraction (XRD and scanning electron spectroscopy (SEM. The XRD investigations of the prepared thin films demonstrate that the crystal structure of glycerol-iron oxide nanoparticles was not changed after spin coating deposition. On the other hand, the SEM micrographs suggest that the size of the glycerol-iron oxide microspheres increased with the increase of glycerol exhibiting narrow size distributions. The qualitative depth profile of glycerol-iron oxide thin films was identified by glow discharge optical emission spectroscopy (GDOES. The GDOES spectra revealed the presence of the main elements: Fe, O, C, H, and Si. The antimicrobial activity of glycerol-iron oxide thin films was evaluated by measuring the zone of inhibition. After 18 hours of incubation at 37°C, the diameters of the zones of complete inhibition have been measured obtaining values around 25 mm.

  17. Disappearance of superconductivity and critical resistance in thin indium films

    International Nuclear Information System (INIS)

    Okuma, Satoshi; Nishida, Nobuhiko

    1991-01-01

    In thin granular films composed of two-dimensionally coupled indium particles, we have studied influences of average particle sizes anti d on the superconducting transition. For films with anti d=280A and 224A, superconducting transition temperature stays almost constant with increasing the sheet resistance R n in the normal state, while for a film with anti d=140A, it decreases linearly with R n . This means that the system changes to a dirty superconductor by reducing anti d. With further increasing R n , superconductivity disappears when R n exceeds the value R c of order h/4e 2 , which seems to correlate with anti d. (orig.)

  18. Effects of process parameters on sheet resistance uniformity of fluorine-doped tin oxide thin films

    Science.gov (United States)

    Hudaya, Chairul; Park, Ji Hun; Lee, Joong Kee

    2012-01-01

    An alternative indium-free material for transparent conducting oxides of fluorine-doped tin oxide [FTO] thin films deposited on polyethylene terephthalate [PET] was prepared by electron cyclotron resonance - metal organic chemical vapor deposition [ECR-MOCVD]. One of the essential issues regarding metal oxide film deposition is the sheet resistance uniformity of the film. Variations in process parameters, in this case, working and bubbler pressures of ECR-MOCVD, can lead to a change in resistance uniformity. Both the optical transmittance and electrical resistance uniformity of FTO film-coated PET were investigated. The result shows that sheet resistance uniformity and the transmittance of the film are affected significantly by the changes in bubbler pressure but are less influenced by the working pressure of the ECR-MOCVD system.

  19. Reversible electrical resistance switching in GeSbTe thin films : An electrolytic approach without amorphous-crystalline phase-change

    NARCIS (Netherlands)

    Pandian, Ramanathaswamy; Kooi, Bart J.; Palasantzas, George; De Hosson, Jeff Th. M.; Wouters, DJ; Hong, S; Soss, S; Auciello, O

    2008-01-01

    Besides the well-known resistance switching originating from the amorphous-crystalline phase-change in GeSbTe thin films, we demonstrate another switching mechanism named 'polarity-dependent resistance (PDR) switching'. 'Me electrical resistance of the film switches between a low- and high-state

  20. Resistive switching in TiO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lin

    2011-10-26

    The continuing improved performance of the digital electronic devices requires new memory technologies which should be inexpensively fabricated for higher integration capacity, faster operation, and low power consumption. Resistive random access memory has great potential to become the front runner as the non volatile memory technology. The resistance states stored in such cell can remain for long time and can be read out none-destructively by a very small electrical pulse. In this work the typically two terminal memory cells containing a thin TiO{sub 2} layer are studied. Polycrystalline TiO{sub 2} thin films are deposited with atomic layer deposition and magnetron reactive sputtering processes, which are both physically and electrically characterized. The resistive switching cells are constructed in a metal/TiO{sub 2}/metal structure. Electroforming process initiate the cell from the beginning good insulator to a real memory cell to program the resistive states. Multilevel resistive bipolar switching controlled by current compliance is the common characteristic observed in these cells, which is potentially to be used as so called multi-bit memory cells to improve the memory capacity. With different top electrodes of Pt, Cu, Ag the resistive switching behaviors are studied. The switching behaviors are different depending on the top metal such as the minimum current compliance, the endurance of the programmed resistance states and the morphology change during the switching. The temperature dependence of different resistance states are investigated. A reduction of the activation energy and their possible conduction mechanisms is discussed on the base of the basic current conduction models. It is found that the resistance state transfers from semiconductor to metallic property with the reducing resistances. The calculated temperature coefficients of their metallic states on the Cu/TiO{sub 2}/Pt and Ag/TiO{sub 2}/Pt are very close to the reported literature data

  1. Structure dependent resistivity and dielectric characteristics of tantalum oxynitride thin films produced by magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Cristea, D., E-mail: daniel.cristea@unitbv.ro [Department of Materials Science, Transilvania University, 500036 Brasov (Romania); Crisan, A. [Department of Materials Science, Transilvania University, 500036 Brasov (Romania); Cretu, N. [Electrical Engineering and Applied Physics Department, Transilvania University, 500036 Brasov (Romania); Borges, J. [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710 - 057 Braga (Portugal); Instituto Pedro Nunes, Laboratório de Ensaios, Desgaste e Materiais, Rua Pedro Nunes, 3030-199 Coimbra (Portugal); SEG-CEMUC, Mechanical Engineering Department, University of Coimbra, 3030-788 Coimbra (Portugal); Lopes, C.; Cunha, L. [Centro de Física, Universidade do Minho, Campus de Gualtar, 4710 - 057 Braga (Portugal); Ion, V.; Dinescu, M. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, “Photonic Processing of Advanced Materials” Group, PO Box MG-16, RO 77125 Magurele-Bucharest (Romania); Barradas, N.P. [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, E.N. 10 ao km 139,7, 2695-066 Bobadela LRS (Portugal); Alves, E. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, E.N. 10 ao km 139,7, 2695-066 Bobadela LRS (Portugal); Apreutesei, M. [MATEIS Laboratory-INSA de Lyon, 21 Avenue Jean Capelle, 69621 Villeurbanne cedex (France); Université de Lyon, Institut des Nanotechnologies de Lyon INL-UMR5270, CNRS, Ecole Centrale de Lyon, Ecully F-69134 (France); Munteanu, D. [Department of Materials Science, Transilvania University, 500036 Brasov (Romania)

    2015-11-01

    Highlights: • Tantalum oxynitride thin films have been deposited by magnetron sputtering, in various configurations. • The rising of the reactive gases mixture flow has the consequence of a gradual increase in the non-metallic content in the films, which results in a 10 orders of magnitude resistivity domain. • The higher resistivity films exhibit dielectric constants up to 41 and quality factors up to 70. - Abstract: The main purpose of this work is to present and to interpret the change of electrical properties of Ta{sub x}N{sub y}O{sub z} thin films, produced by DC reactive magnetron sputtering. Some parameters were varied during deposition: the flow of the reactive gases mixture (N{sub 2} and O{sub 2}, with a constant concentration ratio of 17:3); the substrate voltage bias (grounded, −50 V or −100 V) and the substrate (glass, (1 0 0) Si or high speed steel). The obtained films exhibit significant differences. The variation of the deposition parameters induces variations of the composition, microstructure and morphology. These differences cause variation of the electrical resistivity essentially correlated with the composition and structural changes. The gradual decrease of the Ta concentration in the films induces amorphization and causes a raise of the resistivity. The dielectric characteristics of some of the high resistance Ta{sub x}N{sub y}O{sub z} films were obtained in the samples with a capacitor-like design (deposited onto high speed steel, with gold pads deposited on the dielectric Ta{sub x}N{sub y}O{sub z} films). Some of these films exhibited dielectric constant values higher than those reported for other tantalum based dielectric films.

  2. Intrinsically conductive polymer thin film piezoresistors

    DEFF Research Database (Denmark)

    Lillemose, Michael; Spieser, Martin; Christiansen, N.O.

    2008-01-01

    We report on the piezoresistive effect in the intrinsically conductive polymer, polyaniline. A process recipe for indirect patterning of thin film polyaniline has been developed. Using a specially designed chip, the polyaniline thin films have been characterised with respect to resistivity...

  3. Contact resistance and stability study for Au, Ti, Hf and Ni contacts on thin-film Mg2Si

    KAUST Repository

    Zhang, Bo; Zheng, Tao; Wang, Qingxiao; Zhu, Yihan; Alshareef, Husam N.; Kim, Moon J.; Gnade, Bruce E.

    2016-01-01

    We present a detailed study of post-deposition annealing effects on contact resistance of Au, Ti, Hf and Ni electrodes on Mg2Si thin films. Thin-film Mg2Si and metal contacts were deposited using magnetron sputtering. Various post

  4. Highly uniform resistive switching properties of amorphous InGaZnO thin films prepared by a low temperature photochemical solution deposition method.

    Science.gov (United States)

    Hu, Wei; Zou, Lilan; Chen, Xinman; Qin, Ni; Li, Shuwei; Bao, Dinghua

    2014-04-09

    We report on highly uniform resistive switching properties of amorphous InGaZnO (a-IGZO) thin films. The thin films were fabricated by a low temperature photochemical solution deposition method, a simple process combining chemical solution deposition and ultraviolet (UV) irradiation treatment. The a-IGZO based resistive switching devices exhibit long retention, good endurance, uniform switching voltages, and stable distribution of low and high resistance states. Electrical conduction mechanisms were also discussed on the basis of the current-voltage characteristics and their temperature dependence. The excellent resistive switching properties can be attributed to the reduction of organic- and hydrogen-based elements and the formation of enhanced metal-oxide bonding and metal-hydroxide bonding networks by hydrogen bonding due to UV irradiation, based on Fourier-transform-infrared spectroscopy, X-ray photoelectron spectroscopy, and Field emission scanning electron microscopy analysis of the thin films. This study suggests that a-IGZO thin films have potential applications in resistive random access memory and the low temperature photochemical solution deposition method can find the opportunity for further achieving system on panel applications if the a-IGZO resistive switching cells were integrated with a-IGZO thin film transistors.

  5. Investigation on powder metallurgy Cr-Si-Ta-Al alloy target for high-resistance thin film resistors with low temperature coefficient of resistance

    International Nuclear Information System (INIS)

    Wang, X.Y.; Zhang, Z.S.; Bai, T.

    2010-01-01

    The sputtering target for high-resistance thin film resistors plays a decisive role in temperature coefficient of resistance (TCR). Silicon-rich chromium (Cr)-silicon (Si) target was designed and smelted for high-resistance thin film resistors with low TCR. Valve metal tantalum (Ta) and aluminum (Al) were introduced to the Cr-Si target to improve the performance of the target prepared. The measures for grain refining in smelting Cr-Si-Ta-Al target were taken to improve the performance of the prepared target. The mechanism and role of grain refinement were discussed in the paper. The phase structure of the prepared target was detected by X-ray diffraction (XRD). Rate of temperature drop was studied to reduce the internal stress of alloy target and conquer the easy cracking disadvantage of silicon-rich target. The electrical properties of sputtered thin film resistors were tested to evaluate the performance of the prepared target indirectly.

  6. Enhancement of optical transmittance and electrical resistivity of post-annealed ITO thin films RF sputtered on Si

    Science.gov (United States)

    Ali, Ahmad Hadi; Hassan, Zainuriah; Shuhaimi, Ahmad

    2018-06-01

    This paper reports on the enhancement of optical transmittance and electrical resistivity of indium tin oxide (ITO) transparent conductive oxides (TCO) deposited by radio frequency (RF) sputtering on Si substrate. Post-annealing was conducted on the samples at temperature ranges of 500-700 °C. From X-ray diffraction analysis (XRD), ITO (2 2 2) peak was observed after post-annealing indicating crystallization phase of the films. From UV-vis measurements, the ITO thin film shows highest transmittance of more than 90% at post-annealing temperature of 700 °C as compared to the as-deposited thin films. From atomic force microscope (AFM), the surface roughness becomes smoother after post-annealing as compared to the as-deposited. The lowest electrical resistivity for ITO sample is 6.68 × 10-4 Ω cm after post-annealed at 700 °C that are contributed by high carrier concentration and mobility. The improved structural and surface morphological characteristics helps in increasing the optical transmittance and reducing the electrical resistivity of the ITO thin films.

  7. Thickness and temperature dependence of electrical resistivity of p-type Bi0.5Sb1.5Te3 thin films prepared by flash evaporation method

    International Nuclear Information System (INIS)

    Duan Xingkai; Yang Junyou; Zhu, W; Fan, X A; Bao, S Q

    2006-01-01

    P-type Bi 0.5 Sb 1.5 Te 3 thin films with thicknesses in the range 80-320 nm have been deposited by the flash evaporation method on glass substrates at 473 K. XRD and field emission scanning electron microscope were performed to characterize the thin films. The results show that the thin films are polycrystalline and the grain size of the thin films increases with increasing thickness of the thin films. Compositional analysis of the thin films was also carried out by energy-dispersive x-ray analysis. A near linear relationship was observed between the electrical resistivity and the inverse thickness of the annealed thin films, and it agrees with Tellier's model. Electrical resistivity of the annealed thin films was studied in the temperature range 300-350 K, and their thermal activation behaviour was characterized, the activation energy for conduction decreases with increasing thickness of the thin films

  8. Deposition of Cu-doped PbS thin films with low resistivity using DC sputtering

    Science.gov (United States)

    Soetedjo, Hariyadi; Siswanto, Bambang; Aziz, Ihwanul; Sudjatmoko

    2018-03-01

    Investigation of the electrical resistivity of Cu-doped PbS thin films has been carried out. The films were prepared using a DC sputtering technique. The doping was achieved by introducing the Cu dopant plate material directly on the surface of the PbS sputtering target plate. SEM-EDX data shows the Cu concentration in the PbS film to be proportional to the Cu plate diameter. The XRD pattern indicates the film is in crystalline cubic form. The Hall effect measurement shows that Cu doping yields an increase in the carrier concentration to 3.55 × 1019 cm-3 and a significant decrease in electrical resistivity. The lowest resistivity obtained was 0.13 Ωcm for a Cu concentration of 18.5%. Preferential orientation of (1 1 1) and (2 0 0) occurs during deposition.

  9. Surface microstructures and corrosion resistance of Ni-Ti-Nb shape memory thin films

    Science.gov (United States)

    Li, Kun; Li, Yan; Huang, Xu; Gibson, Des; Zheng, Yang; Liu, Jiao; Sun, Lu; Fu, Yong Qing

    2017-08-01

    Ni-Ti-Nb and Ni-Ti shape memory thin films were sputter-deposited onto silicon substrates and annealed at 600 °C for crystallization. X-ray diffraction (XRD) measurements indicated that all of the annealed Ni-Ti-Nb films were composed of crystalline Ni-Ti (Nb) and Nb-rich grains. X-ray photoelectron spectroscopy (XPS) tests showed that the surfaces of Ni-Ti-Nb films were covered with Ti oxides, NiO and Nb2O5. The corrosion resistance of the Ni-Ti-Nb films in 3.5 wt.% NaCl solution was investigated using electrochemical tests such as open-circuit potential (OCP) and potentio-dynamic polarization tests. Ni-Ti-Nb films showed higher OCPs, higher corrosion potentials (Ecorr) and lower corrosion current densities (icorr) than the binary Ni-Ti film, which indicated a better corrosion resistance. The reason may be that Nb additions modified the passive layer on the film surface. The OCPs of Ni-Ti-Nb films increased with further Nb additions, whereas no apparent difference of Ecorr and icorr was found among the Ni-Ti-Nb films.

  10. Characterization of nanocrystalline cadmium telluride thin films ...

    Indian Academy of Sciences (India)

    Unknown

    tion method, successive ionic layer adsorption and reaction (SILAR), are described. For deposition of CdTe thin films ... By conducting several trials optimization of the adsorption, reaction and rinsing time duration for CdTe thin film .... The electrical resistivity of CdTe films was studied in air. Figure 3 shows the variation of log ...

  11. Influence of Thermal Annealing Treatment on Bipolar Switching Properties of Vanadium Oxide Thin-Film Resistance Random-Access Memory Devices

    Science.gov (United States)

    Chen, Kai-Huang; Cheng, Chien-Min; Kao, Ming-Cheng; Chang, Kuan-Chang; Chang, Ting-Chang; Tsai, Tsung-Ming; Wu, Sean; Su, Feng-Yi

    2017-04-01

    The bipolar switching properties and electrical conduction mechanism of vanadium oxide thin-film resistive random-access memory (RRAM) devices obtained using a rapid thermal annealing (RTA) process have been investigated in high-resistive status/low-resistive status (HRS/LRS) and are discussed herein. In addition, the resistance switching properties and quality improvement of the vanadium oxide thin-film RRAM devices were measured by x-ray diffraction (XRD) analysis, x-ray photoelectron spectrometry (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and current-voltage ( I- V) measurements. The activation energy of the hopping conduction mechanism in the devices was investigated based on Arrhenius plots in HRS and LRS. The hopping conduction distance and activation energy barrier were obtained as 12 nm and 45 meV, respectively. The thermal annealing process is recognized as a candidate method for fabrication of thin-film RRAM devices, being compatible with integrated circuit technology for nonvolatile memory devices.

  12. Fabricating superhydrophobic polymer surfaces with excellent abrasion resistance by a simple lamination templating method.

    Science.gov (United States)

    Xu, Qian Feng; Mondal, Bikash; Lyons, Alan M

    2011-09-01

    Fabricating robust superhydrophobic surfaces for commercial applications is challenging as the fine-scale surface features, necessary to achieve superhydrophobicity, are susceptible to mechanical damage. Herein, we report a simple and inexpensive lamination templating method to create superhydrophobic polymer surfaces with excellent abrasion resistance and water pressure stability. To fabricate the surfaces, polyethylene films were laminated against woven wire mesh templates. After cooling, the mesh was peeled from the polymer creating a 3D array of ordered polymer microposts on the polymer surface. The resulting texture is monolithic with the polymer film and requires no chemical modification to exhibit superhydrophobicity. By controlling lamination parameters and mesh dimensions, polyethylene surfaces were fabricated that exhibit static contact angles of 160° and slip angles of 5°. Chemical and mechanical stability was evaluated using an array of manual tests as well as a standard reciprocating abraser test. Surfaces remained superhydrophobic after more than 5500 abrasion cycles at a pressure of 32.0 kPa. In addition, the surface remains dry after immersing into water for 5 h at 55 kPa. This method is environmental friendly, as it employs no solvents or harsh chemicals and may provide an economically viable path to manufacture large areas of mechanically robust superhydrophobic surfaces from inexpensive polymers and reusable templates.

  13. Characterization and modeling of a highly-oriented thin film for composite forming

    Science.gov (United States)

    White, K. D.; Sherwood, J. A.

    2018-05-01

    Ultra High Molecular Weight Polyethylene (UHMWPE) materials exhibit high impact strength, excellent abrasion resistance and high chemical resistance, making them attractive for a number of impact applications for automotive, marine and medical industries. One format of this class of materials that is being considered for the thermoforming process is a highly-oriented extruded thin film. Parts are made using a two-step manufacturing process that involves first producing a set of preforms and then consolidating these preforms into a final shaped part. To assist in the design of the processing parameters, simulations of the preforming and compression molding steps can be completed using the finite element method. Such simulations require material input data as developed through a comprehensive characterization test program, e.g. shear, tensile and bending, over the range of potential processing temperatures. The current research investigates the challenges associated with the characterization of thin, highly-oriented UHMWPE films. Variations in grip type, sample size and testing rates are explored to achieve convergence of the characterization data. Material characterization results are then used in finite element simulations of the tension test to explore element formulations that work well with the mechanical behavior. Comparisons of the results from the material characterization tests to results of simulations of the same test are performed to validate the finite element method parameters and the credibility of the user-defined material model.

  14. Regulation of the forming process and the set voltage distribution of unipolar resistance switching in spin-coated CoFe2O4 thin films.

    Science.gov (United States)

    Mustaqima, Millaty; Yoo, Pilsun; Huang, Wei; Lee, Bo Wha; Liu, Chunli

    2015-01-01

    We report the preparation of (111) preferentially oriented CoFe2O4 thin films on Pt(111)/TiO2/SiO2/Si substrates using a spin-coating process. The post-annealing conditions and film thickness were varied for cobalt ferrite (CFO) thin films, and Pt/CFO/Pt structures were prepared to investigate the resistance switching behaviors. Our results showed that resistance switching without a forming process is preferred to obtain less fluctuation in the set voltage, which can be regulated directly from the preparation conditions of the CFO thin films. Therefore, instead of thicker film, CFO thin films deposited by two times spin-coating with a thickness about 100 nm gave stable resistance switching with the most stable set voltage. Since the forming process and the large variation in set voltage have been considered as serious obstacles for the practical application of resistance switching for non-volatile memory devices, our results could provide meaningful insights in improving the performance of ferrite material-based resistance switching memory devices.

  15. Abrasion Resistance of as-Cast High-Chromium Cast Iron

    Directory of Open Access Journals (Sweden)

    Pokusová Marcela

    2014-12-01

    Full Text Available High chromium cast irons are widely used as abrasion resistant materials. Their properties and wear resistance depend on carbides and on the nature of the matrix supporting these carbides. The paper presents test results of irons which contain (in wt.% 18-22 Cr and 2-5 C, and is alloyed by 1.7 Mo + 5 Ni + 2 Mn to improve the toughness. Tests showed as-cast irons with mostly austenitic matrix achieved hardness 36-53 HRC but their relative abrasion-resistance was higher than the tool steel STN 19436 heat treated on hardness 60 HRC.

  16. Resistive switching phenomenon and hole wind effect in YBCO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Truchly, Martin; Plecenik, Tomas [Department of Experimental Physics, Comenius University, Bratislava (Slovakia); Zhitlukhina, Elena [Donetsk Institute for Physics and Engineering, Kyiv (Ukraine)

    2016-07-01

    We present an overview of our experimental and theoretical activities aimed to clarify the mechanism of resistive memory effects in YBCO thin layers. The phenomenon was studied by scanning spreading resistance microscopy (SSRM) and scanning tunneling microscopy (STM) techniques. The most striking feature uncovered (in contrast to previous experiments on planar bilayers with YBCO films) was the opposite voltage-bias polarity of the switching effect in all SSRM and a number of STM measurements. Observed hysteresis in current-voltage characteristics is interpreted as a movement of oxygen vacancies in the vicinity of the tip-YBCO contact. Since the charge distribution in YBCO samples is expected to be strongly inhomogeneous, the balance between the direct electrostatic force on activated oxygen ions and that caused by momentum exchange with the current carriers (holes) hitting them determines direction in which the oxygen vacancies are moving. We propose a minimalist model with the only fitting parameter that accounts for the resistance hysteresis phenomenon in the YBCO films studied.

  17. Fabrication of graphene-nanoflake/poly(4-vinylphenol) polymer nanocomposite thin film by electrohydrodynamic atomization and its application as flexible resistive switching device

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Kyung Hyun; Ali, Junaid [Department of Mechatronics Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of); Na, Kyoung-Hoan, E-mail: khna@dankook.ac.kr [College of Engineering, Dankook University, Yongin-si, Gyeonggi-do 448-701 (Korea, Republic of)

    2015-10-15

    This paper describes synthesis of graphene/poly(4-vinylphenol) (PVP) nanocomposite and deposition of thin film by electrohydrodynamic atomization (EHDA) for fabrication flexible resistive switching device. EHDA technique proved its viability for thin film deposition after surface morphology analyses by field emission scanning electron microscope (FESEM) and non-destructive 3D Nano-profilometry, as the deposited films were, devoid of abnormalities. The commercially available graphene micro-flakes were exfoliated and broken down to ultra-small (20 nm–200 nm) nano-flakes by ultra-sonication in presence of N-methyl-pyrrolidone (NMP). These graphene nanoflakes with PVP nanocomposite, were successfully deposited as thin films (thickness ~140±7 nm, R{sub a}=2.59 nm) on indium–tin-oxide (ITO) coated polyethylene terephthalate (PET) substrate. Transmittance data revealed that thin films are up to ~87% transparent in visible and NIR region. Resistive switching behaviour of graphene/PVP nanocomposite thin film was studied by using the nanocomposite as active layer in Ag/active layer/ITO sandwich structure. The resistive switching devices thus fabricated, showed characteristic OFF to ON (high resistance to low resistance) transition at low voltages, when operated between ±3 V, characterized at 10 nA compliance currents. The devices fabricated by this approach exhibited a stable room temperature, low power current–voltage hysteresis and well over 1 h retentivity, and R{sub OFF}/R{sub ON}≈35:1. The device showed stable flexibility up to a minimum bending diameter of 1.8 cm.

  18. Nanostructured thin film coatings with different strengthening effects

    Directory of Open Access Journals (Sweden)

    Panfilov Yury

    2017-01-01

    Full Text Available A number of articles on strengthening thin film coatings were analyzed and a lot of unusual strengthening effects, such as super high hardness and plasticity simultaneously, ultra low friction coefficient, high wear-resistance, curve rigidity increasing of drills with small diameter, associated with process formation of nanostructured coatings by the different thin film deposition methods were detected. Vacuum coater with RF magnetron sputtering system and ion-beam source and arc evaporator for nanostructured thin film coating manufacture are represented. Diamond Like Carbon and MoS2 thin film coatings, Ti, Al, Nb, Cr, nitride, carbide, and carbo-nitride thin film materials are described as strengthening coatings.

  19. Surface morphology modelling for the resistivity analysis of low temperature sputtered indium tin oxide thin films on polymer substrates

    International Nuclear Information System (INIS)

    Yin Xuesong; Tang Wu; Weng Xiaolong; Deng Longjiang

    2009-01-01

    Amorphous or weakly crystalline indium tin oxide (ITO) thin film samples have been prepared on polymethylmethacrylate and polyethylene terephthalate substrates by RF-magnetron sputtering at a low substrate temperature. The surface morphological and electrical properties of the ITO layers were measured by atomic force microscopy (AFM) and a standard four-point probe measurement. The effect of surface morphology on the resistivity of ITO thin films was studied, which presented some different variations from crystalline films. Then, a simplified film system model, including the substrate, continuous ITO layer and ITO surface grain, was proposed to deal with these correlations. Based on this thin film model and the AFM images, a quadratic potential was introduced to simulate the characteristics of the ITO surface morphology, and the classical Kronig-Penney model, the semiconductor electrical theory and the modified Neugebauer-Webb model were used to expound the detailed experimental results. The modelling equation was highly in accord with the experimental variations of the resistivity on the characteristics of the surface morphology.

  20. Resistance switching in epitaxial SrCoO{sub x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk, E-mail: cu-jung@hufs.ac.kr [Department of Physics, Hankuk University of Foreign Studies, Yongin 449-791 (Korea, Republic of); Kim, Yeon Soo; Park, Bae Ho [Division of Quantum Phases and Devices, Department of Physics, Konkuk University, Seoul 143-791 (Korea, Republic of); Jeong, Huiseong; Park, Ji-Yong [Department of Physics and Division of Energy System Research, Ajou University, Suwon 443-749 (Korea, Republic of); Cho, Myung Rae; Park, Yun Daniel [Department of Physics and Astronomy and Center for Subwavelength Optics, Seoul National University, Seoul 151-747 (Korea, Republic of); Choi, Woo Seok [Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, Dong-Wook [Department of Physics, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Jin, Hyunwoo; Lee, Suyoun [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong [Department of Material Science and Engineering, Seoul National University, Seoul 151-747 (Korea, Republic of)

    2014-08-11

    We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO{sub 3} (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO{sub 2.5}) and conducting perovskite (SrCoO{sub 3−δ}) depending on the oxygen content. The current–voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoO{sub x} thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO{sub 2.5}.

  1. Investigation of interfacial resistance between LiCoO{sub 2} cathode and LiPON electrolyte in the thin film battery

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Eunkyung; Hong, Chan; Tak, Yongsug [Department of Chemical Engineering, Inha University, Inchon 402-751 (Korea, Republic of); Nam, Sang Cheol [Nuricell Inc., Jungrang-Ku, Seoul 131-220 (Korea, Republic of); Cho, Sungbaek [Agency for Defense Development, P.O. Box 35, Daejeon (Korea, Republic of)

    2006-09-13

    All solid-state thin film battery was prepared with conventional sputtering technologies. Low conductivity of lithium phosphorus oxynitride (LiPON) electrolyte and higher resistance at the interface of LiCoO{sub 2}/LiPON was crucial for the development of thin film battery. Presence of thermally treated Al{sub 2}O{sub 3} thin film at the interface of LiCoO{sub 2}/LiPON decreased the interfacial resistance and increased the discharge capacity with the better cycling behaviors. Surface analysis and electrochemical impedance measurement indicate the formation of solid solution LiCo{sub 1-y}Al{sub y}O{sub 2} at the interface of LiCoO{sub 2}/LiPON. (author)

  2. Fabrication of ATO/Graphene Multi-layered Transparent Conducting Thin Films

    Science.gov (United States)

    Li, Na; Chen, Fei; Shen, Qiang; Wang, Chuanbin; Zhang, Lianmeng

    2013-03-01

    A novel transparent conducting oxide based on the ATO/graphene multi-layered thin films has been developed to satisfy the application of transparent conductive electrode in solar cells. The ATO thin films are prepared by pulsed laser deposition method with high quality, namely the sheet resistance of 49.5 Ω/sq and average transmittance of 81.9 %. The prepared graphene sheet is well reduced and shows atomically thin, spotty distributed appearance on the top of the ATO thin films. The XRD and optical micrographs are used to confirm the successfully preparation of the ATO/graphene multi-layered thin films. The Hall measurements and UV-Vis spectrophotometer are conducted to evaluate the sheet resistance and optical transmittance of the innovative structure. It is found that graphene can improve the electrical properties of the ATO thin films with little influence on the optical transmittance.

  3. Fabrication of ATO/Graphene Multi-layered Transparent Conducting Thin Films

    International Nuclear Information System (INIS)

    Li Na; Chen Fei; Shen Qiang; Wang Chuanbin; Zhang Lianmeng

    2013-01-01

    A novel transparent conducting oxide based on the ATO/graphene multi-layered thin films has been developed to satisfy the application of transparent conductive electrode in solar cells. The ATO thin films are prepared by pulsed laser deposition method with high quality, namely the sheet resistance of 49.5 Ω/sq and average transmittance of 81.9 %. The prepared graphene sheet is well reduced and shows atomically thin, spotty distributed appearance on the top of the ATO thin films. The XRD and optical micrographs are used to confirm the successfully preparation of the ATO/graphene multi-layered thin films. The Hall measurements and UV-Vis spectrophotometer are conducted to evaluate the sheet resistance and optical transmittance of the innovative structure. It is found that graphene can improve the electrical properties of the ATO thin films with little influence on the optical transmittance.

  4. Corrosion resistance of the NdFeB coated with AlN/SiC bilayer thin films by magnetron sputtering under different environments

    International Nuclear Information System (INIS)

    Tao, Lei; Li, Heqin; Shen, Jiong; Qiao, Kai; Wang, Wei; Zhou, Chu; Zhang, Jing; Tang, Qiong

    2015-01-01

    The AlN/SiC bilayer and SiC monolayer thin films were deposited on sintered NdFeB by RF magnetron sputtering to improve the corrosion resistance. Their structures and morphologies were studied by XRD and AFM and SEM. The corrosion behaviors of AlN/SiC and SiC-coated NdFeB in 3.5 wt% NaCl, 20 wt% NaOH and 0.1 mol/L H 2 SO 4 solutions were characterized with potentiodynamic polarization curves. The results show that AlN/SiC and SiC thin films can evidently improve the corrosion resistance of NdFeB, and the AlN/SiC films have the better resistance than the SiC film. - Highlights: • SiC monolayer and AlN/SiC bilayer thin films have been prepared on NdFeB at room temperature by RF magnetron sputtering. • NdFeB coated with AlN/SiC bilayer films has more corrosion resistance than that coated with SiC monolayer film under different environments. • The grains of the AlN/SiC bilayer films are finer and the surface roughness is lower than that of SiC monolayer film

  5. Corrosion resistance of the NdFeB coated with AlN/SiC bilayer thin films by magnetron sputtering under different environments

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Lei [School of Materials Science and Engineering, Hefei University of Technology, Anhui Hefei 230009 (China); Li, Heqin, E-mail: lhqjs@hfut.edu.cn [School of Materials Science and Engineering, Hefei University of Technology, Anhui Hefei 230009 (China); Shen, Jiong [Earth-Panda Advance Magnetic Material Co., Ltd., Anhui Lujiang 231500 (China); Qiao, Kai; Wang, Wei; Zhou, Chu [School of Materials Science and Engineering, Hefei University of Technology, Anhui Hefei 230009 (China); Zhang, Jing; Tang, Qiong [School of Materials Science and Engineering, Hefei University of Technology, Anhui Hefei 230009 (China); School of Electronic Science and Applied Physics, Hefei University of Technology, Anhui Hefei 230009 (China)

    2015-02-01

    The AlN/SiC bilayer and SiC monolayer thin films were deposited on sintered NdFeB by RF magnetron sputtering to improve the corrosion resistance. Their structures and morphologies were studied by XRD and AFM and SEM. The corrosion behaviors of AlN/SiC and SiC-coated NdFeB in 3.5 wt% NaCl, 20 wt% NaOH and 0.1 mol/L H{sub 2}SO{sub 4} solutions were characterized with potentiodynamic polarization curves. The results show that AlN/SiC and SiC thin films can evidently improve the corrosion resistance of NdFeB, and the AlN/SiC films have the better resistance than the SiC film. - Highlights: • SiC monolayer and AlN/SiC bilayer thin films have been prepared on NdFeB at room temperature by RF magnetron sputtering. • NdFeB coated with AlN/SiC bilayer films has more corrosion resistance than that coated with SiC monolayer film under different environments. • The grains of the AlN/SiC bilayer films are finer and the surface roughness is lower than that of SiC monolayer film.

  6. Fabrication and Performance Study of Uniform Thin Film Integrated ...

    African Journals Online (AJOL)

    The transmission line model of a uniform rectangular thin film R-C-KR structure consisting of a dielectric layer of constant per unit shunt capacitance C sandwiched between two resistive thin films of constant per unit length resistances R and KR has been analysed using the concept of matrix parameter functions. The above ...

  7. Wear resistance and structural changes in nitrogen-containing high-chromium martensitic steels under conditions of abrasive wear and sliding friction

    International Nuclear Information System (INIS)

    Makarov, A.V.; Korshunov, L.G.; Schastlivtsev, V.M.; Chernenko, N.L.

    1998-01-01

    Martensitic nitrogen-containing steels Kh17N2A0.14, Kh13A0.14, Kh14G4A0.22 as well as steel 20Kh13 were studied for their wear resistance under conditions of friction and abrasion. Metallography, X ray diffraction analysis and electron microscopy were used to investigate the structural changes taking place in a thin surface layer on wearing. It is shown that an increase of nitrogen content of 0.14 to 0.22% promotes an enhancement of steel resistance to abrasive and adhesive wear, especially after tempering in the range of 500-550 deg C. Typically, the nitrogen-containing steels exhibit lower resistance to various types of wear in comparison with the steels with high-carbon martensite due to their lower deformability under conditions of friction loading

  8. A New Concept for Non-Volatile Memory: The Electric-Pulse Induced Resistive Change Effect in Colossal Magnetoresistive Thin Films

    Science.gov (United States)

    Liu, S. Q.; Wu, N. J.; Ignatiev, A.

    2001-01-01

    A novel electric pulse-induced resistive change (EPIR) effect has been found in thin film colossal magnetoresistive (CMR) materials, and has shown promise for the development of resistive, nonvolatile memory. The EPIR effect is induced by the application of low voltage (resistance of the thin film sample depending on pulse polarity. The sample resistance change has been shown to be over two orders of magnitude, and is nonvolatile after pulsing. The sample resistance can also be changed through multiple levels - as many as 50 have been shown. Such a device can provide a way for the development of a new kind of nonvolatile multiple-valued memory with high density, fast write/read speed, low power-consumption, and potential high radiation-hardness.

  9. Si-based thin film coating on Y-TZP: Influence of deposition parameters on adhesion of resin cement

    Energy Technology Data Exchange (ETDEWEB)

    Queiroz, José Renato Cavalcanti, E-mail: joserenatocq@hotmail.com [Potiguar University, Department of Biotechnology, Natal (Brazil); Nogueira Junior, Lafayette [São Paulo State University, Department of Prosthodontics and Dental Materials, São José dos Campos (Brazil); Massi, Marcos [Federal University of São Paulo, Institute of Science and Technology, São José dos Campos (Brazil); Silva, Alecssandro de Moura; Bottino, Marco Antonio [São Paulo State University, Department of Prosthodontics and Dental Materials, São José dos Campos (Brazil); Sobrinho, Argemiro Soares da Silva [Technological Institute of Aeronautics, Department of Physics, São José dos Campos (Brazil); Özcan, Mutlu [University of Zurich, Dental Materials Unit, Center for Dental and Oral Medicine, Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, Zurich (Switzerland)

    2013-10-01

    This study evaluated the influence of deposition parameters for Si-based thin films using magnetron sputtering for coating zirconia and subsequent adhesion of resin cement. Zirconia ceramic blocks were randomly divided into 8 groups and specimens were either ground finished and polished or conditioned using air-abrasion with alumina particles coated with silica. In the remaining groups, the polished specimens were coated with Si-based film coating with argon/oxygen magnetron discharge at 8:1 or 20:1 flux. In one group, Si-based film coating was performed on air-abraded surfaces. After application of bonding agent, resin cement was bonded. Profilometry, goniometry, Energy Dispersive X-ray Spectroscopy and Rutherford Backscattering Spectroscopy analysis were performed on the conditioned zirconia surfaces. Adhesion of resin cement to zirconia was tested using shear bond test and debonded surfaces were examined using Scanning Electron Microscopy. Si-based film coating applied on air-abraded rough zirconia surfaces increased the adhesion of the resin cement (22.78 ± 5.2 MPa) compared to those of other methods (0–14.62 MPa) (p = 0.05). Mixed type of failures were more frequent in Si film coated groups on either polished or air-abraded groups. Si-based thin films increased wettability compared to the control group but did not change the roughness, considering the parameters evaluated. Deposition parameters of Si-based thin film and after application of air-abrasion influenced the initial adhesion of resin cement to zirconia.

  10. Si-based thin film coating on Y-TZP: Influence of deposition parameters on adhesion of resin cement

    International Nuclear Information System (INIS)

    Queiroz, José Renato Cavalcanti; Nogueira Junior, Lafayette; Massi, Marcos; Silva, Alecssandro de Moura; Bottino, Marco Antonio; Sobrinho, Argemiro Soares da Silva; Özcan, Mutlu

    2013-01-01

    This study evaluated the influence of deposition parameters for Si-based thin films using magnetron sputtering for coating zirconia and subsequent adhesion of resin cement. Zirconia ceramic blocks were randomly divided into 8 groups and specimens were either ground finished and polished or conditioned using air-abrasion with alumina particles coated with silica. In the remaining groups, the polished specimens were coated with Si-based film coating with argon/oxygen magnetron discharge at 8:1 or 20:1 flux. In one group, Si-based film coating was performed on air-abraded surfaces. After application of bonding agent, resin cement was bonded. Profilometry, goniometry, Energy Dispersive X-ray Spectroscopy and Rutherford Backscattering Spectroscopy analysis were performed on the conditioned zirconia surfaces. Adhesion of resin cement to zirconia was tested using shear bond test and debonded surfaces were examined using Scanning Electron Microscopy. Si-based film coating applied on air-abraded rough zirconia surfaces increased the adhesion of the resin cement (22.78 ± 5.2 MPa) compared to those of other methods (0–14.62 MPa) (p = 0.05). Mixed type of failures were more frequent in Si film coated groups on either polished or air-abraded groups. Si-based thin films increased wettability compared to the control group but did not change the roughness, considering the parameters evaluated. Deposition parameters of Si-based thin film and after application of air-abrasion influenced the initial adhesion of resin cement to zirconia.

  11. Thin-Film layers with Interfaces that reduce RF Losses on High-Resistivity Silicon Substrates

    NARCIS (Netherlands)

    Evseev, S. B.; Milosavljevic, S.; Nanver, L. K.

    2017-01-01

    Radio-Frequency (RF) losses on High-Resistivity Silicon (HRS) substrates were studied for several different surface passivation layers comprising thin-films of SiC, SiN and SiO2 In many combinations, losses from conductive surface channels were reduced and increasing the number of interfaces between

  12. Method of preparing high-temperature-stable thin-film resistors

    Science.gov (United States)

    Raymond, L.S.

    1980-11-12

    A chemical vapor deposition method for manufacturing tungsten-silicide thin-film resistors of predetermined bulk resistivity and temperature coefficient of resistance (TCR) is disclosed. Gaseous compounds of tungsten and silicon are decomposed on a hot substrate to deposit a thin-film of tungsten-silicide. The TCR of the film is determined by the crystallinity of the grain structure, which is controlled by the temperature of deposition and the tungsten to silicon ratio. The bulk resistivity is determined by the tungsten to silicon ratio. Manipulation of the fabrication parameters allows for sensitive control of the properties of the resistor.

  13. Method of preparing high-temperature-stable thin-film resistors

    International Nuclear Information System (INIS)

    Raymond, L.S.

    1983-01-01

    A chemical vapor deposition method is disclosed for manufacturing tungsten-silicide thin-film resistors of predetermined bulk resistivity and temperature coefficient of resistance (TCR). Gaseous compounds of tungsten and silicon are decomposed on a hot substrate to deposit a thin-film of tungsten-silicide. The TCR of the film is determined by the crystallinity of the grain structure, which is controlled by the temperature of deposition and the tungsten to silicon ratio. The bulk resistivity is determined by the tungsten to silicon ratio. Manipulation of the fabrication parameters allows for sensitive control of the properties of the resistor

  14. Resistive switching of organic–inorganic hybrid devices of conductive polymer and permeable ultra-thin SiO2 films

    Science.gov (United States)

    Yamamoto, Shunsuke; Kitanaka, Takahisa; Miyashita, Tokuji; Mitsuishi, Masaya

    2018-06-01

    We propose a resistive switching device composed of conductive polymer (PEDOT:PSS) and SiO2 ultra-thin films. The SiO2 film was fabricated from silsesquioxane polymer nanosheets as a resistive switching layer. Devices with metal (Ag or Au)∣SiO2∣PEDOT:PSS architecture show good resistive switching performance with set–reset voltages as low as several hundred millivolts. The device properties and the working mechanism were investigated by varying the electrode material, surrounding atmosphere, and SiO2 film thickness. Results show that resistive switching is based on water and ion migration at the PEDOT:PSS∣SiO2 interface.

  15. Development of abrasion resistant glass-ceramics from industrial waste products. Final report

    Energy Technology Data Exchange (ETDEWEB)

    von Roode, M.

    1983-05-26

    Slag-ceramics were produced from glass compositions using pelletized slag as the major ingredient. The abrasion resistance, fracture toughness and microstructure of the prepared glass and glass-ceramics were evaluated. Glas-ceramics with good abrasion resistance were obtained when iron oxide in conjunction with carbon was used as a nucleating agent. 5 figs., 11 tabs.

  16. Elevated transition temperature in Ge doped VO2 thin films

    Science.gov (United States)

    Krammer, Anna; Magrez, Arnaud; Vitale, Wolfgang A.; Mocny, Piotr; Jeanneret, Patrick; Guibert, Edouard; Whitlow, Harry J.; Ionescu, Adrian M.; Schüler, Andreas

    2017-07-01

    Thermochromic GexV1-xO2+y thin films have been deposited on Si (100) substrates by means of reactive magnetron sputtering. The films were then characterized by Rutherford backscattering spectrometry (RBS), four-point probe electrical resistivity measurements, X-ray diffraction, and atomic force microscopy. From the temperature dependent resistivity measurements, the effect of Ge doping on the semiconductor-to-metal phase transition in vanadium oxide thin films was investigated. The transition temperature was shown to increase significantly upon Ge doping (˜95 °C), while the hysteresis width and resistivity contrast gradually decreased. The precise Ge concentration and the film thickness have been determined by RBS. The crystallinity of phase-pure VO2 monoclinic films was confirmed by XRD. These findings make the use of vanadium dioxide thin films in solar and electronic device applications—where higher critical temperatures than 68 °C of pristine VO2 are needed—a viable and promising solution.

  17. Dry lithography of large-area, thin-film organic semiconductors using frozen CO(2) resists.

    Science.gov (United States)

    Bahlke, Matthias E; Mendoza, Hiroshi A; Ashall, Daniel T; Yin, Allen S; Baldo, Marc A

    2012-12-04

    To address the incompatibility of organic semiconductors with traditional photolithography, an inert, frozen CO(2) resist is demonstrated that forms an in situ shadow mask. Contact with a room-temperature micro-featured stamp is used to pattern the resist. After thin film deposition, the remaining CO(2) is sublimed to lift off unwanted material. Pixel densities of 325 pixels-per-inch are shown. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Non-ohmic transport behavior in ultra-thin gold films

    International Nuclear Information System (INIS)

    Alkhatib, A.; Souier, T.; Chiesa, M.

    2011-01-01

    Highlights: → C-AFM study on ultra-thin gold films. → Connection between ultra-thin film morphology and lateral electrical transport. → Transition between ohmic and non-ohmic behavior. → Electrical transition correlation to the film structure continuity. → Direct and indirect tunneling regimes related to discontinuous structures. - Abstract: Structure and local lateral electrical properties of Au films of thicknesses ranging from 10 to 140 nm are studied using conductive atomic force microscopy. Comparison of current maps taken at different thicknesses reveals surprising highly resistive regions (10 10 -10 11 Ω), the density of which increases strongly at lower thickness. The high resistivity is shown to be directly related to discontinuities in the metal sheet. Local I-V curves are acquired to show the nature of electrical behavior relative to thickness. Results show that in Au films of higher thickness the electrical behavior is ohmic, while it is non-ohmic in highly discontinuous films of lower thickness, with the transition happening between 34 and 39 nm. The non-ohmic behavior is explained with tunneling occurring between separated Au islands. The results explain the abrupt increase of electrical resistivity at lower thin film thicknesses.

  19. Properties of Spray Pyrolysied Copper Oxide Thin Films

    Directory of Open Access Journals (Sweden)

    S. S. Roy

    2017-02-01

    Full Text Available Copper oxide (CuO thin films were deposited on well cleaned glass substrates by spray pyrolysis technique (SPT from cupric acetate (Cu(CH3COO2.H2O precursor solutions of 0.05 – 0.15 M molar concentrations (MC at a substrate temperature of 350 °C and at an air pressure of 1 bar. Effect of varying MC on the surface morphology, structural optical and electrical properties of CuO thin films were investigated. XRD patterns of the prepared films revealed the formation of CuO thin films having monoclinic structure with the main CuO (111 orientation and crystalline size ranging from 8.02 to 9.05 nm was observed. The optical transmission of the film was found to decrease with the increase of MC. The optical band gap of the thin films for 0.10 M was fond to be 1.60 eV. The room temperature electrical resistivity varies from 31 and 24 ohm.cm for the films grown with MC of 0.05 and 0.10 M respectively. The change in resistivity of the films was studied with respect to the change in temperature was shown that semiconductor nature is present. This information is expected to underlie the successful development of CuO films for solar windows and other semi-conductor applications including gas sensors.

  20. Hall effect of K-doped superconducting thin films

    Energy Technology Data Exchange (ETDEWEB)

    Son, Eunseon; Lee, Nam Hoon; Kang, Won Nam [Dept. of physics, Sungkyunkwan University, Suwon (Korea, Republic of); Hwang, Tae Jong; Kim, Dong Ho [Dept. of physics, Yeungnam University, Gyeongsan(Korea, Republic of)

    2013-09-15

    We have studied Hall effect for potassium (K)-doped BaFe{sub 2}As{sub 2}superconducting thin films by analyzing the relation between the longitudinal resistivity (ρ{sub xy}) and the Hall resistivity (ρ{sub xy}). The thin films used in this study were fabricated on Al{sub O3} (000l) substrates by using an ex-situ pulsed laser deposition (PLD) technique under a high-vacuum condition of ∼10{sup -6} Torr. The samples showed the high superconducting transition temperatures (T{sub C}) of ∼40 K. The ρ{sub xx} and ρ{sub xy}the for K-doped BaFeAs{sub 2} thin films were measured by using a physical property measurement system (PPMS) with a temperature sweep (T-sweep) mode at an applied current density of 100 A/cm{sup 2} and at magnetic fields from 0 up to 9 T. We report the T-sweep results of the ρ{sub xx} and the ρ{sub xy} to investigate Hall scaling behavior on the basis of the relation of ρ{sub xy} = A(ρ{sub xy}){sup β}. The ρ{sub xx} values are 3.0 ± 0.2 in the c-axis-oriented K-doped BaFeAs{sub 2} thin films, whereas the thin films with various oriented-directions like a polycrystal showed slightly lower β than that of c-axis-oriented thin films. Interestingly, the β value is decreased with increasing magnetic fields.

  1. Nanomechanical Behavior of High Gas Barrier Multilayer Thin Films.

    Science.gov (United States)

    Humood, Mohammad; Chowdhury, Shahla; Song, Yixuan; Tzeng, Ping; Grunlan, Jaime C; Polycarpou, Andreas A

    2016-05-04

    Nanoindentation and nanoscratch experiments were performed on thin multilayer films manufactured using the layer-by-layer (LbL) assembly technique. These films are known to exhibit high gas barrier, but little is known about their durability, which is an important feature for various packaging applications (e.g., food and electronics). Films were prepared from bilayer and quadlayer sequences, with varying thickness and composition. In an effort to evaluate multilayer thin film surface and mechanical properties, and their resistance to failure and wear, a comprehensive range of experiments were conducted: low and high load indentation, low and high load scratch. Some of the thin films were found to have exceptional mechanical behavior and exhibit excellent scratch resistance. Specifically, nanobrick wall structures, comprising montmorillonite (MMT) clay and polyethylenimine (PEI) bilayers, are the most durable coatings. PEI/MMT films exhibit high hardness, large elastic modulus, high elastic recovery, low friction, low scratch depth, and a smooth surface. When combined with the low oxygen permeability and high optical transmission of these thin films, these excellent mechanical properties make them good candidates for hard coating surface-sensitive substrates, where polymers are required to sustain long-term surface aesthetics and quality.

  2. Mathematical model of temperature field distribution in thin plates during polishing with a free abrasive

    Directory of Open Access Journals (Sweden)

    Avilov Alex

    2017-01-01

    Full Text Available The purpose of this paper is to estimate the dynamic characteristics of the heating process of thin plates during polishing with a free abrasive. A mathematical model of the temperature field distribution in space and time according to the plate thickness is based on Lagrange equation of the second kind in the thermodynamics of irreversible processes (variation principle Bio. The research results of thermo elasticity of thin plates (membranes will allow to correct the modes of polishing with a free abrasive to receive the exact reflecting surfaces of satellites reflector, to increase temperature stability and the ability of radio signal reflection, satellite precision guidance. Calculations of temperature fields in thin plates of different thicknesses (membranes is held in the Excel, a graphical characteristics of temperature fields in thin plates (membranes show non-linearity of temperature distribution according to the thickness of thin plates (membranes.

  3. Chemical resistance of thin film materials based on metal oxides grown by atomic layer deposition

    International Nuclear Information System (INIS)

    Sammelselg, Väino; Netšipailo, Ivan; Aidla, Aleks; Tarre, Aivar; Aarik, Lauri; Asari, Jelena; Ritslaid, Peeter; Aarik, Jaan

    2013-01-01

    Etching rate of technologically important metal oxide thin films in hot sulphuric acid was investigated. The films of Al-, Ti-, Cr-, and Ta-oxides studied were grown by atomic layer deposition (ALD) method on silicon substrates from different precursors in large ranges of growth temperatures (80–900 °C) in order to reveal process parameters that allow deposition of coatings with higher chemical resistance. The results obtained demonstrate that application of processes that yield films with lower concentration of residual impurities as well as crystallization of films in thermal ALD processes leads to significant decrease of etching rate. Crystalline films of materials studied showed etching rates down to values of < 5 pm/s. - Highlights: • Etching of atomic layer deposited thin metal oxide films in hot H 2 SO 4 was studied. • Smallest etching rates of < 5 pm/s for TiO 2 , Al 2 O 3 , and Cr 2 O 3 were reached. • Highest etching rate of 2.8 nm/s for Al 2 O 3 was occurred. • Remarkable differences in etching of non- and crystalline films were observed

  4. Abnormal resistance switching behaviours of NiO thin films: possible occurrence of both formation and rupturing of conducting channels

    Energy Technology Data Exchange (ETDEWEB)

    Liu Chunli; Chae, S C; Chang, S H; Lee, S B; Noh, T W [ReCOE and FPRD, Department of Physics and Astronomy, Seoul National University, Seoul 151-747 (Korea, Republic of); Lee, J S; Kahng, B [Department of Physics and Astronomy, Seoul National University, Seoul 151-747 (Korea, Republic of); Kim, D-W [Division of Nano Sciences and Department of Physics, Ewha Womens University, Seoul 120-750 (Korea, Republic of); Jung, C U [Department of Physics, Hankuk University of Foreign Studies, Yongin, Gyeonggi-do 449-791 (Korea, Republic of); Seo, S; Ahn, S-E [Samsung Advanced Institute of Technology, Suwon 440-600 (Korea, Republic of)], E-mail: twnoh@snu.ac.kr

    2009-01-07

    We report a detailed study on the abnormal resistance switching behaviours observed in NiO thin films which show unipolar resistance switching phenomena. During the RESET process, in which the NiO film changed from a low resistance state to a high resistance state, we sometimes observed that the resistance became smaller than the initial value. We simulated the resistance switching by using a random circuit breaker network model. We found that local conducting channels could be formed as well as ruptured during the RESET process, which result in the occurrence of such abnormal switching behaviours.

  5. Defect engineering of SrTiO{sub 3} thin films for resistive switching applications

    Energy Technology Data Exchange (ETDEWEB)

    Wicklein, Sebastian

    2013-11-19

    As a matter of fact, the importance of (transition) metal oxides for modern applications in the field of energy and information technology (IT) for e.g. novel energy storage systems and solid state electronic devices is increasing. Previous studies discovered the importance of defects in an oxide for their functionality and emphasized the impact of stoichiometry on the oxide performance. A new field of interest of the memory technology sector is the so-called resistive switching phenomena where a voltage stimulus causes a thin oxide (≤10 nm) to change its resistance state from a high resistance state to a low resistance state and back. So called resistive RAM (ReRAM or RRAM) are deemed to be the future replacement (2015) for contemporary FLASH memory technology due to its extremely low energy consumption, its very fast read/write time (ns) and its possible node size <10 nm. A key challenge for the investigation of oxides and their electronic properties is the management and controlled incorporation of defects in the thin film oxide. Within this work, SrTiO{sub 3} was used as an oxide model material and was deposited by pulsed laser deposition (PLD) onto doped and undoped SrTiO{sub 3} single crystals to investigate the formation of defects as a function of the process parameters. By combining structural and chemical thin film analysis with detailed PLD plume diagnostics and modeling of the laser plume dynamics, it was possible to elucidate the different physical mechanisms determining the stoichiometry of SrTiO{sub 3} during PLD. Deviations between thin film and target stoichiometry are basically a result of two effects, namely, incongruent ablation and preferential scattering of lighter ablated species during their motion towards the substrate in the O{sub 2} background gas. It is shown that the SrTiO{sub 3} system reacts to a non-stoichiometry with the systematic incorporation of titanium and strontium vacancies which could be detected by positron annihilation

  6. Development of Ultrafast Laser Flash Methods for Measuring Thermophysical Properties of Thin Films and Boundary Thermal Resistances

    Science.gov (United States)

    Baba, Tetsuya; Taketoshi, Naoyuki; Yagi, Takashi

    2011-11-01

    Reliable thermophysical property values of thin films are important to develop advanced industrial technologies such as highly integrated electronic devices, phase-change memories, magneto-optical disks, light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs), semiconductor lasers (LDs), flat-panel displays, and power electronic devices. In order to meet these requirements, the National Metrology Institute of Japan of the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) has developed ultrafast laser flash methods heated by picosecond pulse or nanosecond pulse with the same geometrical configuration as the laser flash method, which is the standard method to measure the thermal diffusivity of bulk materials. Since these pulsed light heating methods induce one-dimensional heat diffusion across a well-defined length of the specimen thickness, the absolute value of thermal diffusivity across thin films can be measured reliably. Using these ultrafast laser flash methods, the thermal diffusivity of each layer of multilayered thin films and the boundary thermal resistance between the layers can be determined from the observed transient temperature curves based on the response function method. The thermophysical properties of various thin films important for modern industries such as the transparent conductive films used for flat-panel displays, hard coating films, and multilayered films of next-generation phase-change optical disks have been measured by these methods.

  7. Photoconductivity of thin organic films

    International Nuclear Information System (INIS)

    Tkachenko, Nikolai V.; Chukharev, Vladimir; Kaplas, Petra; Tolkki, Antti; Efimov, Alexander; Haring, Kimmo; Viheriaelae, Jukka; Niemi, Tapio; Lemmetyinen, Helge

    2010-01-01

    Thin organic films were deposited on silicon oxide surfaces with golden interdigitated electrodes (interelectrode gap was 2 μm), and the film resistivities were measured in dark and under white light illumination. The compounds selected for the measurements include molecules widely used in solar cell applications, such as polythiophene (PHT), fullerene (C 60 ), pyrelene tetracarboxylic diimide (PTCDI) and copper phthalocyanine (CuPc), as well as molecules potentially interesting for photovoltaic applications, e.g. porphyrin-fullerene dyads. The films were deposited using thermal evaporation (e.g. for C 60 and CuPc films), spin coating for PHT, and Langmuir-Schaeffer for the layer-by-layer deposition of porphyrin-fullerene dyads. The most conducting materials in the series are films of PHT and CuPc with resistivities 1.2 x 10 3 Ω m and 3 x 10 4 Ω m, respectively. Under light illumination resistivity of all films decreases, with the strongest light effect observed for PTCDI, for which resistivity decreases by 100 times, from 3.2 x 10 8 Ω m in dark to 3.1 x 10 6 Ω m under the light.

  8. Assessment of thermal spray coatings for wear and abrasion resistance applications

    Science.gov (United States)

    Karode, Ishaan Nitin

    Thermal spray cermet and metallic coatings are extensively used for wear, abrasion and corrosion control in a variety of industries. The first part of the thesis focuses mainly on testing of sand erosion resistance of thermal spray coatings on carbon composites used in the manufacture of helicopter rotor blades. The test set-up employed is a sand blasting machine and is an effort to duplicate the in-flight conditions especially those encountered in hot arid conditions. The technique adopted follows the Department of Defence test method standard. Carbon Composites have excellent stiffness, strength and low weight/density. The strength to weight ratio is high. Hence, these are used in aerospace applications to a large extent. However, the biggest problem encountered with carbon composites is its low abrasion resistance as its surface is very weak. Hence, thermal spray coatings are used to improve the surface properties of CFRP. Zinc bond coats and WC-Co coatings were tested. However, high amount of thermal stresses were developed between the substrate and the coating due to large differences in the CTE's of the both, leading to high mass losses within two minutes and just 130 grams of sand sprayed on to the coatings with the sand blasting machine built; and hence the coatings with CC as a substrate could not qualify for the application. The second part of the thesis focuses on the assessment of different thermal spray coatings used for manufacture of mechanical seals in pumps and analyze the best coating material for the wear resistance application through detail quantification of material loss by block-on-ring test set-up. A machine based on Block-on-ring test set-up following ASTM G77 (Measurement of Adhesive wear resistance of thermal spray coatings) standards was built to duplicate the pump conditions. Thermally sprayed coated materials were tested in different conditions (Load, time, abrasive). WC-Co had the highest wear resistance (lower volume losses) and

  9. Reliable and Damage-Free Estimation of Resistivity of ZnO Thin Films for Photovoltaic Applications Using Photoluminescence Technique

    Directory of Open Access Journals (Sweden)

    N. Poornima

    2013-01-01

    Full Text Available This work projects photoluminescence (PL as an alternative technique to estimate the order of resistivity of zinc oxide (ZnO thin films. ZnO thin films, deposited using chemical spray pyrolysis (CSP by varying the deposition parameters like solvent, spray rate, pH of precursor, and so forth, have been used for this study. Variation in the deposition conditions has tremendous impact on the luminescence properties as well as resistivity. Two emissions could be recorded for all samples—the near band edge emission (NBE at 380 nm and the deep level emission (DLE at ~500 nm which are competing in nature. It is observed that the ratio of intensities of DLE to NBE (/ can be reduced by controlling oxygen incorporation in the sample. - measurements indicate that restricting oxygen incorporation reduces resistivity considerably. Variation of / and resistivity for samples prepared under different deposition conditions is similar in nature. / was always less than resistivity by an order for all samples. Thus from PL measurements alone, the order of resistivity of the samples can be estimated.

  10. Improvement of physical properties of IGZO thin films prepared by excimer laser annealing of sol–gel derived precursor films

    International Nuclear Information System (INIS)

    Tsay, Chien-Yie; Huang, Tzu-Teng

    2013-01-01

    Indium gallium zinc oxide (IGZO) transparent semiconductor thin films were prepared by KrF excimer laser annealing of sol–gel derived precursor films. Each as-coated film was dried at 150 °C in air and then annealed using excimer laser irradiation. The influence of laser irradiation energy density on surface conditions, optical transmittances, and electrical properties of laser annealed IGZO thin films were investigated, and the physical properties of the excimer laser annealed (ELA) and the thermally annealed (TA) thin films were compared. Experimental results showed that two kinds of surface morphology resulted from excimer laser annealing. Irradiation with a lower energy density (≤250 mJ cm −2 ) produced wavy and irregular surfaces, while irradiation with a higher energy density (≥350 mJ cm −2 ) produced flat and dense surfaces consisting of uniform nano-sized amorphous particles. The explanation for the differences in surface features and film quality is that using laser irradiation energy to form IGZO thin films improves the film density and removes organic constituents. The dried IGZO sol–gel films irradiated with a laser energy density of 350 mJ/cm 2 had the best physical properties of all the ELA IGZO thin films. The mean resistivity of the ELA 350 thin films (4.48 × 10 3 Ω cm) was lower than that of TA thin films (1.39 × 10 4 Ω cm), and the average optical transmittance in the visible range (90.2%) of the ELA 350 thin films was slightly higher than that of TA thin films (89.7%). - Highlights: • IGZO semiconductor films were prepared by laser annealing of sol–gel derived films. • Surface roughness and resistivity of ELA samples were affected by energy density. • The ELA 350 IGZO film exhibited the best properties among all of ELA IGZO films. • Transmittance and resistivity of ELA 350 films are greater than those of TA films

  11. Improvement of physical properties of IGZO thin films prepared by excimer laser annealing of sol–gel derived precursor films

    Energy Technology Data Exchange (ETDEWEB)

    Tsay, Chien-Yie, E-mail: cytsay@fcu.edu.tw; Huang, Tzu-Teng

    2013-06-15

    Indium gallium zinc oxide (IGZO) transparent semiconductor thin films were prepared by KrF excimer laser annealing of sol–gel derived precursor films. Each as-coated film was dried at 150 °C in air and then annealed using excimer laser irradiation. The influence of laser irradiation energy density on surface conditions, optical transmittances, and electrical properties of laser annealed IGZO thin films were investigated, and the physical properties of the excimer laser annealed (ELA) and the thermally annealed (TA) thin films were compared. Experimental results showed that two kinds of surface morphology resulted from excimer laser annealing. Irradiation with a lower energy density (≤250 mJ cm{sup −2}) produced wavy and irregular surfaces, while irradiation with a higher energy density (≥350 mJ cm{sup −2}) produced flat and dense surfaces consisting of uniform nano-sized amorphous particles. The explanation for the differences in surface features and film quality is that using laser irradiation energy to form IGZO thin films improves the film density and removes organic constituents. The dried IGZO sol–gel films irradiated with a laser energy density of 350 mJ/cm{sup 2} had the best physical properties of all the ELA IGZO thin films. The mean resistivity of the ELA 350 thin films (4.48 × 10{sup 3} Ω cm) was lower than that of TA thin films (1.39 × 10{sup 4} Ω cm), and the average optical transmittance in the visible range (90.2%) of the ELA 350 thin films was slightly higher than that of TA thin films (89.7%). - Highlights: • IGZO semiconductor films were prepared by laser annealing of sol–gel derived films. • Surface roughness and resistivity of ELA samples were affected by energy density. • The ELA 350 IGZO film exhibited the best properties among all of ELA IGZO films. • Transmittance and resistivity of ELA 350 films are greater than those of TA films.

  12. Surface proton transport of fully protonated poly(aspartic acid) thin films on quartz substrates

    Science.gov (United States)

    Nagao, Yuki; Kubo, Takahiro

    2014-12-01

    Thin film structure and the proton transport property of fully protonated poly(aspartic acid) (P-Asp100) have been investigated. An earlier study assessed partially protonated poly(aspartic acid), highly oriented thin film structure and enhancement of the internal proton transport. In this study of P-Asp100, IR p-polarized multiple-angle incidence resolution (P-MAIR) spectra were measured to investigate the thin film structure. The obtained thin films, with thicknesses of 120-670 nm, had no oriented structure. Relative humidity dependence of the resistance, proton conductivity, and normalized resistance were examined to ascertain the proton transport property of P-Asp100 thin films. The obtained data showed that the proton transport of P-Asp100 thin films might occur on the surface, not inside of the thin film. This phenomenon might be related with the proton transport of the biological system.

  13. Resistivity of thin gold films on mica induced by electron-surface scattering: Application of quantitative scanning tunneling microscopy

    International Nuclear Information System (INIS)

    Robles, Marcelo E.; Gonzalez-Fuentes, Claudio A.; Henriquez, Ricardo; Kremer, German; Moraga, Luis; Oyarzun, Simón; Suarez, Marco Antonio; Flores, Marcos; Munoz, Raul C.

    2012-01-01

    We report a comparison between the resistivity measured on thin gold films deposited on mica, with predictions based upon classical theories of size effects (Drude's, Sondheimer's and Calecki's), as well as predictions based upon quantum theories of electron-surface scattering (the modified theory of Sheng, Xing and Wang, the theory of Tesanovic, Jaric and Maekawa, and that of Trivedi and Aschroft). From topographic images of the surface recorded with a Scanning Tunneling Microscope, we determined the rms roughness amplitude, δ and the lateral correlation length, ξ corresponding to a Gaussian representation of the average height-height autocorrelation function, describing the roughness of each sample in the scale of length set by the Fermi wave length. Using (δ, ξ) as input data, we present a rigorous comparison between resistivity data and predictions based upon the theory of Calecki as well as quantum theoretical predictions without adjustable parameters. The resistivity was measured on gold films of different thickness evaporated onto mica substrates, between 4 K and 300 K. The resistivity data covers the range 0.1 < x(T) < 6.8, for 4 K < T < 300 K, where x(T) is the ratio between film thickness and electron mean free path in the bulk at temperature T. We experimentally identify electron-surface and electron-phonon scattering as the microscopic electron scattering mechanisms giving rise to the macroscopic resistivity. The different theories are all capable of estimating the thin film resistivity to an accuracy better than 10%; however the mean free path and the resistivity characterizing the bulk turn out to depend on film thickness. Surprisingly, only the Sondheimer theory and its quantum version, the modified theory of Sheng, Xing and Wang, predict and increase in resistivity induced by size effects that seems consistent with published galvanomagnetic phenomena also arising from electron-surface scattering measured at low temperatures.

  14. Triclosan-immobilized polyamide thin film composite membranes with enhanced biofouling resistance

    Science.gov (United States)

    Park, Sang-Hee; Hwang, Seon Oh; Kim, Taek-Seung; Cho, Arah; Kwon, Soon Jin; Kim, Kyoung Taek; Park, Hee-Deung; Lee, Jung-Hyun

    2018-06-01

    We report on a strategy to improve biofouling resistance of a polyamide (PA) thin-film composite (TFC) reverse osmosis (RO) membrane via chemically immobilizing triclosan (TC), known as a common organic biocide, on its surface. To facilitate covalent attachment of TC on the membrane surface, TC was functionalized with amine moiety to prepare aminopropyl TC. Then, the TC-immobilized TFC (TFC-TC) membranes were fabricated through a one-step amide formation reaction between amine groups of aminopropyl TC and acyl chloride groups present on the PA membrane surface, which was confirmed by high-resolution XPS. Strong stability of the immobilized TC was also confirmed by a hydraulic washing test. Although the TFC-TC membrane showed slightly reduced separation performance compared to the pristine control, it still maintained a satisfactory RO performance level. Importantly, the TFC-TC membrane exhibited excellent antibacterial activity against both gram negative (E. coli and P. aeruginosa) and gram positive (S. aureus) bacteria along with greatly enhanced resistance to biofilm formation. Our immobilization approach offers a robust and relatively benign strategy to control biofouling of functional surfaces, films and membranes.

  15. Studies on resistive switching times in NiO thin films grown by pulsed laser deposition

    International Nuclear Information System (INIS)

    Misra, P; Sahu, V K; Ajimsha, R S; Das, A K; Singh, B

    2017-01-01

    The resistive switching dynamics of NiO thin films in Au/NiO/Pt device configuration have been investigated to measure the switching times of set and reset events and their dependence on compliance current and switching voltages. The set switching time was found to be ∼10 ns at the set voltage of ∼1.8 V, while reset switching time was much longer ∼150 µ s at reset voltage of 0.8 V. With increasing compliance current from 5 to 75 mA during set process, although the resistance contrast of two states improved due to the decrease in the resistance of the low resistance state, the reset switching time increased substantially up to ∼3 ms while set time remained nearly unchanged. The fast reset switching time of ∼27 ns, comparable to that of set switching time, was achieved by applying a higher reset voltage of ∼1.2 V. The observed dependence of reset time on compliance current and reset voltage in NiO thin films was explained in light of the conducting filamentary model in which reset process is of thermal nature and involves dissolution of conducting filaments as a consequence of Joule heating generated by the reset current. (paper)

  16. Thin film oxygen partial pressure sensor

    Science.gov (United States)

    Wortman, J. J.; Harrison, J. W.; Honbarrier, H. L.; Yen, J.

    1972-01-01

    The development is described of a laboratory model oxygen partial pressure sensor using a sputtered zinc oxide thin film. The film is operated at about 400 C through the use of a miniature silicon bar. Because of the unique resistance versus temperature relation of the silicon bar, control of the operational temperature is achieved by controlling the resistance. A circuit for accomplishing this is described. The response of sputtered zinc oxide films of various thicknesses to oxygen, nitrogen, argon, carbon dioxide, and water vapor caused a change in the film resistance. Over a large range, film conductance varied approximately as the square root of the oxygen partial pressure. The presence of water vapor in the gas stream caused a shift in the film conductance at a given oxygen partial pressure. A theoretical model is presented to explain the characteristic features of the zinc oxide response to oxygen.

  17. Repulsive effects of hydrophobic diamond thin films on biomolecule detection

    Energy Technology Data Exchange (ETDEWEB)

    Ruslinda, A. Rahim, E-mail: ruslindarahim@gmail.com [Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Jln Kgr-Alor Setar, Seriab, 01000 Kangar, Perlis (Malaysia); Department of Nano Science and Nano Engineering, School of Advance Science and Engineering, Ohkubo 3-4-1, Shinjuku, 169-8555 Tokyo (Japan); Ishiyama, Y. [Department of Nano Science and Nano Engineering, School of Advance Science and Engineering, Ohkubo 3-4-1, Shinjuku, 169-8555 Tokyo (Japan); Penmatsa, V. [Department of Mechanical and Materials Engineering, Florida International University, 10555 West Flagler Street, Miami, FL 33174 (United States); Ibori, S.; Kawarada, H. [Department of Nano Science and Nano Engineering, School of Advance Science and Engineering, Ohkubo 3-4-1, Shinjuku, 169-8555 Tokyo (Japan)

    2015-02-15

    Highlights: • We report the effect of fluorine plasma treatment on diamond thin film to resist the nonspecific adsorption of biomolecules. • The diamond thin film were highly hydrophobic with a surface energy value of ∼25 mN/m. • The repulsive effect shows excellent binding efficiency for both DNA and HIV-1 Tat protein. - Abstract: The repulsive effect of hydrophobic diamond thin film on biomolecule detection, such as single-nucleotide polymorphisms and human immunodeficiency virus type 1 trans-activator of transcription peptide protein detection, was investigated using a mixture of a fluorine-, amine-, and hydrogen-terminated diamond surfaces. These chemical modifications lead to the formation of a surface that effectively resists the nonspecific adsorption of proteins and other biomolecules. The effect of fluorine plasma treatment on elemental composition was also investigated via X-ray photoelectron spectroscopy (XPS). XPS results revealed a fluorocarbon layer on the diamond thin films. The contact angle measurement results indicated that the fluorine-treated diamond thin films were highly hydrophobic with a surface energy value of ∼25 mN/m.

  18. Repulsive effects of hydrophobic diamond thin films on biomolecule detection

    International Nuclear Information System (INIS)

    Ruslinda, A. Rahim; Ishiyama, Y.; Penmatsa, V.; Ibori, S.; Kawarada, H.

    2015-01-01

    Highlights: • We report the effect of fluorine plasma treatment on diamond thin film to resist the nonspecific adsorption of biomolecules. • The diamond thin film were highly hydrophobic with a surface energy value of ∼25 mN/m. • The repulsive effect shows excellent binding efficiency for both DNA and HIV-1 Tat protein. - Abstract: The repulsive effect of hydrophobic diamond thin film on biomolecule detection, such as single-nucleotide polymorphisms and human immunodeficiency virus type 1 trans-activator of transcription peptide protein detection, was investigated using a mixture of a fluorine-, amine-, and hydrogen-terminated diamond surfaces. These chemical modifications lead to the formation of a surface that effectively resists the nonspecific adsorption of proteins and other biomolecules. The effect of fluorine plasma treatment on elemental composition was also investigated via X-ray photoelectron spectroscopy (XPS). XPS results revealed a fluorocarbon layer on the diamond thin films. The contact angle measurement results indicated that the fluorine-treated diamond thin films were highly hydrophobic with a surface energy value of ∼25 mN/m

  19. Resistive switching: An investigation of the bipolar–unipolar transition in Co-doped ZnO thin films

    International Nuclear Information System (INIS)

    Santos, Daniel A.A.; Zeng, Hao; Macêdo, Marcelo A.

    2015-01-01

    Highlights: • A purely bipolar behavior on a Co-doped ZnO thin film has been demonstrated. • We have shown what can happen if a unipolar test is performed in a purely bipolar device. • An explanation for how a sample can show a purely bipolar switching behavior was suggested. • An important open issue about resistive switching effect was put in debate. - Abstract: In order to investigate the resistive switching effect we built devices in a planar structure in which two Al contacts were deposited on the top of the film and separated by a small gap using a shadow mask. Therefore, two samples of 10% Co-doped ZnO thin films were sputtered on glass substrate. High resolution X-ray diffraction (HRXRD) revealed a highly c-axis oriented crystalline structure, without secondary phase. The high resolution scanning electron microscopy (HRSEM) showed a flat surface with good coverage and thickness about 300 nm. A Keithley 2425 semiconductor characterization system was used to perform the resistive switching tests in the bipolar and unipolar modes. Considering only the effect of compliance current (CC), the devices showed a purely bipolar behavior since an increase in CC did not induce a transition to unipolar behavior

  20. Preparation and properties of KCl-doped Cu2O thin film by electrodeposition

    International Nuclear Information System (INIS)

    Yu, Xiaojiao; Li, Xinming; Zheng, Gang; Wei, Yuchen; Zhang, Ama; Yao, Binghua

    2013-01-01

    With the indium tin oxide-coated glass as working electrode, cuprous oxide thin film is fabricated by means of electrodeposition. The effects of KCl doped and annealing treatment upon Cu 2 O thin film morphology, surface resistivity, open-circuit voltage, electric conduction types and visible light response are studied. The research results indicate that KCl doped has a great effect upon Cu 2 O crystal morphology, thus, making Cu 2 O thin film surface resistivity drop, and the open-circuit voltage increase and that electric conduction types are transformed from p type into n type, and the visible light (400–500 nm) absorption rate is slightly reduced. Annealing treatment can obviously decrease Cu 2 O thin film surface resistivity and improve its open-circuit voltage. When KCl concentration in electrolytic solution reaches 7 mmol/L, Cu 2 O thin film morphology can be changed from the dendritic crystal into the cubic crystal and Cu 2 O thin film surface resistivity decreases from the initial 2.5 × 10 6 Ω cm to 8.5 × 10 4 Ω cm. After annealing treatment at 320 °C for 30 min, the surface resistivity decreases to 8.5 × 10 2 Ω cm, and the open-circuit voltage increases from the initial 3.1 mV to 79.2 mV.

  1. Fracture resistance of dental nickel–titanium rotary instruments with novel surface treatment: Thin film metallic glass coating

    Directory of Open Access Journals (Sweden)

    Chih-Wen Chi

    2017-05-01

    Conclusion: The novel surface treatment of Ti-Zr-B thin film metallic glass on dental NiTi rotary files can effectively improve the fatigue fracture resistance by offering a smooth coated surface with amorphous microstructure.

  2. FY 2000 report on the results of the technology development of energy use reduction of machine tools. Development of dry cutting use abrasion resistant/lubricous coated tools; 2000 nendo energy shiyo gorika kosaku kikai nado gijutsu kaihatsu seika hokokusho. Dry sessakuyo taimamo junkatsusei hifuku kogu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    For the purpose of energy conservation and reduction of environmental loads of machine tools, study was conducted on the dry cutting which is the cutting with no use of cutting oil, and the FY 2000 results were summed up. The study was made on dry cutting use abrasion resistance/lubricous coated tools coated with the composite membrane of which the cutting life become little lower than that of existing tools using coolant. In the survey of abrasion resistant/lubricous films, it was found out that in the adhesion to ultra-hard substrates, the DLC single-layer film consisting only of carbon indicated the same excellent adhesion as intermediate-layer inserts. As to the synthesis of abrasion resistant/lubricous films, the synthesis of the composite membrane (WC/C membrane) consisting of tungsten carbide (WC) and carbon (C) was made using arc ion plating device. The WC/C membrane is composed of W and C and has the structure in which at nm levels the layer with much W and the layer with less W were alternately piled. Study was made of devices necessary for the development of abrasion resistant/lubricous films and the film formation for drill. (NEDO)

  3. HYDRO-ABRASIVE RESISTANCE AND MECHANICAL PROPERTIES OF CONCRETE WITH ADDED FLY ASH

    OpenAIRE

    Ristić, Nenad; Grdić, Zoran; Topličić-Ćurčić, Gordana

    2015-01-01

    The durability of hydraulic engineering structures mostly depends on the resistance of their concrete surfaces to mechanical abrasion. In this paper, we study the hydro-abrasive resistance and mechanical properties of concrete in which cement is partially replaced with fly ash in various proportions. To evaluate these concretes, we measured their compressive strength, flexural strength, static modulus of elasticity, ultrasound velocity through concrete, and sclerometer rebound. The hydro-abra...

  4. Power Generation by Zinc Antimonide Thin Film under Various Load Resistances at its Critical Operating Temperature

    DEFF Research Database (Denmark)

    Mir Hosseini, Seyed Mojtaba; Rezaniakolaei, Alireza; Rosendahl, Lasse Aistrup

    slightly reduces during unload conditions, although it is expected that by eliminating load in each step, the initial amount of voltage exactly repeats. Similar behavior is observed for Seebeck coefficient distribution versus time of working particularly in lower load resistances. Based on variation...... thin films operating under different load resistances at around its critical operating temperature, 400 ᵒC. The thermoelement is subjected to constant hot side temperature and to room temperature at the cold junction in order to measure the thin film TEG’s sample performance. The nominal loads equal...... to 10, 15, 20, 25, 30, 35, 40, 45… 175, and also 200 Ohms were applied. The results show that the value of the Seebeck coefficient is 0.0002 [V/K] for the specimen, which is in agreement with quantities of other zinc antimonide bulks materials in literature. The results also show that the voltage...

  5. Surface proton transport of fully protonated poly(aspartic acid) thin films on quartz substrates

    Energy Technology Data Exchange (ETDEWEB)

    Nagao, Yuki, E-mail: ynagao@jaist.ac.jp; Kubo, Takahiro

    2014-12-30

    Graphical abstract: - Highlights: • Proton transport of fully protonated poly(aspartic acid) thin film was investigated. • The thin film structure differed greatly from the partially protonated one. • Proton transport occurs on the surface, not inside of the thin film. • This result contributes to biological transport systems such as bacteriorhodopsin. - Abstract: Thin film structure and the proton transport property of fully protonated poly(aspartic acid) (P-Asp100) have been investigated. An earlier study assessed partially protonated poly(aspartic acid), highly oriented thin film structure and enhancement of the internal proton transport. In this study of P-Asp100, IR p-polarized multiple-angle incidence resolution (P-MAIR) spectra were measured to investigate the thin film structure. The obtained thin films, with thicknesses of 120–670 nm, had no oriented structure. Relative humidity dependence of the resistance, proton conductivity, and normalized resistance were examined to ascertain the proton transport property of P-Asp100 thin films. The obtained data showed that the proton transport of P-Asp100 thin films might occur on the surface, not inside of the thin film. This phenomenon might be related with the proton transport of the biological system.

  6. Surface proton transport of fully protonated poly(aspartic acid) thin films on quartz substrates

    International Nuclear Information System (INIS)

    Nagao, Yuki; Kubo, Takahiro

    2014-01-01

    Graphical abstract: - Highlights: • Proton transport of fully protonated poly(aspartic acid) thin film was investigated. • The thin film structure differed greatly from the partially protonated one. • Proton transport occurs on the surface, not inside of the thin film. • This result contributes to biological transport systems such as bacteriorhodopsin. - Abstract: Thin film structure and the proton transport property of fully protonated poly(aspartic acid) (P-Asp100) have been investigated. An earlier study assessed partially protonated poly(aspartic acid), highly oriented thin film structure and enhancement of the internal proton transport. In this study of P-Asp100, IR p-polarized multiple-angle incidence resolution (P-MAIR) spectra were measured to investigate the thin film structure. The obtained thin films, with thicknesses of 120–670 nm, had no oriented structure. Relative humidity dependence of the resistance, proton conductivity, and normalized resistance were examined to ascertain the proton transport property of P-Asp100 thin films. The obtained data showed that the proton transport of P-Asp100 thin films might occur on the surface, not inside of the thin film. This phenomenon might be related with the proton transport of the biological system

  7. Resistance to abrasion of extrinsic porcelain esthetic characterization techniques.

    Science.gov (United States)

    Chi, Woo J; Browning, William; Looney, Stephen; Mackert, J Rodway; Windhorn, Richard J; Rueggeberg, Frederick

    2017-01-01

    A novel esthetic porcelain characterization technique involves mixing an appropriate amount of ceramic colorants with clear, low-fusing porcelain (LFP), applying the mixture on the external surfaces, and firing the combined components onto the surface of restorations in a porcelain oven. This method may provide better esthetic qualities and toothbrush abrasion resistance compared to the conventional techniques of applying color-corrective porcelain colorants alone, or applying a clear glaze layer over the colorants. However, there is no scientific literature to support this claim. This research evaluated toothbrush abrasion resistance of a novel porcelain esthetic characterization technique by subjecting specimens to various durations of simulated toothbrush abrasion. The results were compared to those obtained using the conventional characterization techniques of colorant application only or colorant followed by placement of a clear over-glaze. Four experimental groups, all of which were a leucite reinforced ceramic of E TC1 (Vita A1) shade, were prepared and fired in a porcelain oven according to the manufacturer's instructions. Group S (stain only) was characterized by application of surface colorants to provide a definitive shade of Vita A3.5. Group GS (glaze over stain) was characterized by application of a layer of glaze over the existing colorant layer as used for Group S. Group SL (stain+LFP) was characterized by application of a mixture of colorants and clear low-fusing add-on porcelain to provide a definitive shade of Vita A3.5. Group C (Control) was used as a control without any surface characterization. The 4 groups were subjected to mechanical toothbrushing using a 1:1 water-to-toothpaste solution for a simulated duration of 32 years of clinical use. The amount of wear was measured at time intervals simulating every 4 years of toothbrushing. These parameters were evaluated longitudinally for all groups as well as compared at similar time points among

  8. Study on the Preparation and Properties of Colored Iron Oxide Thin Films

    International Nuclear Information System (INIS)

    Zhao Xianhui; Li Changhong; Liu Qiuping; He Junjing; Wang Hai; Liang Song; Duan Yandong; Liu Su

    2013-01-01

    Colored iron oxide thin films were prepared using Sol-gel technique. The raw materials were tetraethyl orthosilicate (TEOS), etoh ehanol (EtOH), iron nitrate, and de-ionized water. Various properties were measured and analysed, including the colour of thin films, surface topography, UV-Visible spectra, corrosion resistance and hydrophobicity. To understand how these properties influenced the structural and optical properties of Fe 2 O 3 thin films, Scanning Electron Microscope (SEM), UV Spectrophotometer and other facilities were employed. Many parameters influence the performance of thin films, such as film layers, added H 2 O content, and the amount of polydimethylsiloxane (PDMS). When the volume ratio of TEOS, EtOH and H 2 O was 15: 13: 1, the quality of Fe(NO 3 ) 3 ·9H 2 O was 6g, and pH value was 3, reddish and uniform Fe 2 O 3 thin films with excellent properties were produced. Obtained thin films possessed corrosion resistance in hydrochloric acid with pH=l and the absorption edge wavelength was ∼350.2nm. Different H 2 O contents could result in different morphologies of Fe 2 O 3 nanoparticles. When 1.5 ml PDMS was added into the Sol, thin films possessed hydrophobiliry without dropping. Coating with different layers, thin films appeared different morphologies. Meanwhile, with the increment of film layers, the absorbance increased gradually.

  9. Fabrication and electrical resistivity of Mo-doped VO2 thin films coated on graphite conductive plates by a sol-gel method

    Energy Technology Data Exchange (ETDEWEB)

    Choi, W.; Jung, H.M.; Um, S. [Hanyang Univ., Seoul (Korea, Republic of). School of Mechanical Engineering

    2008-07-01

    Vanadium oxides (VO2) can be used in optical devices, thermochromic smart windows and sensors. This paper reported on a study in which vanadium pentoxide (V2O5) powder was prepared and mixed with Molybdenum Oxides (MoO3) to form Mo-doped and -undoped VO2 thin films by a sol-gel method on graphite conductive substrates. The micro-structure and chemical compositions of the Mo-doped and -undoped VO2 thin films was investigated using X-Ray diffraction and scanning electron microscopy. Changes in electrical resistivity were measured as a function of the stoichiometric compositions between vanadium and molybdenum. In this study. Mo-doped and -undoped VO2 thin films showed the typical metal to insulator transition (MIT), where temperature range could be adjusted by modifying the dopant atomic ratio. The through-plane substrate structure of the Mo-doped layer influences the electrical resistivity of the graphite substrate. As the amount of the molybdenum increases, the electrical resistivity of the graphite conductive substrate decreases in the lower temperature range below the freezing point of water. The experimental results showed that if carefully controlled, thermal dissipation of VO2 thin films can be used as a self-heating source to melt frozen water with the electrical current flowing through the graphite substrate. 3 refs., 3 figs.

  10. Crack density and electrical resistance in indium-tin-oxide/polymer thin films under cyclic loading

    KAUST Repository

    Mora Cordova, Angel

    2014-11-01

    Here, we propose a damage model that describes the degradation of the material properties of indium-tin-oxide (ITO) thin films deposited on polymer substrates under cyclic loading. We base this model on our earlier tensile test model and show that the new model is suitable for cyclic loading. After calibration with experimental data, we are able to capture the stress-strain behavior and changes in electrical resistance of ITO thin films. We are also able to predict the crack density using calibrations from our previous model. Finally, we demonstrate the capabilities of our model based on simulations using material properties reported in the literature. Our model is implemented in the commercially available finite element software ABAQUS using a user subroutine UMAT.[Figure not available: see fulltext.].

  11. Bipolar and unipolar resistive switching behaviors of sol–gel-derived SrTiO3 thin films with different compliance currents

    International Nuclear Information System (INIS)

    Tang, M H; Wang, Z P; Zeng, Z Q; Xu, X L; Wang, G Y; Zhang, L B; Xiao, Y G; Yang, S B; Jiang, B; Li, J C; He, J

    2011-01-01

    The SrTiO 3 (STO) thin films on a Pt/Ti/SiO 2 /Si substrate were synthesized using a sol–gel method to form a metal–insulator–metal structure. This device shows the bipolar resistance switching (BRS) behavior for a compliance current I cc of less than 0.1 mA but exhibits soft breakdown at a higher level of compliance current. A transition from the BRS behavior to the stable unipolar resistive switching behavior (URS) was also observed. We found that the BRS behavior may be controlled by the structure interface while the URS behavior is likely bulk controlled. Our study indicates that the external compliance current is a key factor in resistance switching phenomenon of STO thin films

  12. Preparation and Analysis of Platinum Thin Films for High Temperature Sensor Applications

    Science.gov (United States)

    Wrbanek, John D.; Laster, Kimala L. H.

    2005-01-01

    A study has been made of platinum thin films for application as high temperature resistive sensors. To support NASA Glenn Research Center s high temperature thin film sensor effort, a magnetron sputtering system was installed recently in the GRC Microsystems Fabrication Clean Room Facility. Several samples of platinum films were prepared using various system parameters to establish run conditions. These films were characterized with the intended application of being used as resistive sensing elements, either for temperature or strain measurement. The resistances of several patterned sensors were monitored to document the effect of changes in parameters of deposition and annealing. The parameters were optimized for uniformity and intrinsic strain. The evaporation of platinum via oxidation during annealing over 900 C was documented, and a model for the process developed. The film adhesion was explored on films annealed to 1000 C with various bondcoats on fused quartz and alumina. From this compiled data, a list of optimal parameters and characteristics determined for patterned platinum thin films is given.

  13. Transition metal carbide nanocomposite and amorphous thin films

    OpenAIRE

    Tengstrand, Olof

    2014-01-01

    This thesis explores thin films of binary and ternary transition metal carbides, in the Nb-C, Ti-Si-C, Nb-Si-C, Zr-Si-C, and Nb-Ge-C systems. The electrical and mechanical properties of these systems are affected by their structure and here both nanocomposite and amorphous thin films are thus investigated. By appropriate choice of transition metal and composition the films can be designed to be multifunctional with a combination of properties, such as low electric resistivity, low contact res...

  14. Contact resistance and stability study for Au, Ti, Hf and Ni contacts on thin-film Mg2Si

    KAUST Repository

    Zhang, Bo

    2016-12-28

    We present a detailed study of post-deposition annealing effects on contact resistance of Au, Ti, Hf and Ni electrodes on Mg2Si thin films. Thin-film Mg2Si and metal contacts were deposited using magnetron sputtering. Various post-annealing temperatures were studied to determine the thermal stability of each contact metal. The specific contact resistivity (SCR) was determined using the Cross Bridge Kelvin Resistor (CBKR) method. Ni contacts exhibits the best thermal stability, maintaining stability up to 400 °C, with a SCR of approximately 10−2 Ω-cm2 after annealing. The increased SCR after high temperature annealing is correlated with the formation of a Mg-Si-Ni mixture identified by cross-sectional scanning transmission electron microscopy (STEM) characterization, X-ray diffraction characterization (XRD) and other elemental analyses. The formation of this Mg-Si-Ni mixture is attributed to Ni diffusion and its reaction with the Mg2Si film.

  15. Defect engineering of SrTiO3 thin films for resistive switching applications

    International Nuclear Information System (INIS)

    Wicklein, Sebastian

    2013-01-01

    As a matter of fact, the importance of (transition) metal oxides for modern applications in the field of energy and information technology (IT) for e.g. novel energy storage systems and solid state electronic devices is increasing. Previous studies discovered the importance of defects in an oxide for their functionality and emphasized the impact of stoichiometry on the oxide performance. A new field of interest of the memory technology sector is the so-called resistive switching phenomena where a voltage stimulus causes a thin oxide (≤10 nm) to change its resistance state from a high resistance state to a low resistance state and back. So called resistive RAM (ReRAM or RRAM) are deemed to be the future replacement (2015) for contemporary FLASH memory technology due to its extremely low energy consumption, its very fast read/write time (ns) and its possible node size 3 was used as an oxide model material and was deposited by pulsed laser deposition (PLD) onto doped and undoped SrTiO 3 single crystals to investigate the formation of defects as a function of the process parameters. By combining structural and chemical thin film analysis with detailed PLD plume diagnostics and modeling of the laser plume dynamics, it was possible to elucidate the different physical mechanisms determining the stoichiometry of SrTiO 3 during PLD. Deviations between thin film and target stoichiometry are basically a result of two effects, namely, incongruent ablation and preferential scattering of lighter ablated species during their motion towards the substrate in the O 2 background gas. It is shown that the SrTiO 3 system reacts to a non-stoichiometry with the systematic incorporation of titanium and strontium vacancies which could be detected by positron annihilation lifetime spectroscopy. The role of extrinsic dopands such as Fe is shown to have more complicated effects on the SrTiO 3 system than portrayed by theoretical considerations. The effect of defects on the resistive

  16. Correlation between structural and electrical properties of ZnO thin films

    International Nuclear Information System (INIS)

    Asadov, A.; Gao, W.; Li, Z.; Lee, J.; Hodgson, M.

    2005-01-01

    Thin ZnO films were deposited by radio frequency (r.f.) and direct current (d.c.) magnetron sputtering techniques onto glass substrates. Microstructural and electrical properties of ZnO films were studied using X-ray diffractometer (XRD), scanning electron microscope (SEM) and resistivity measurements. It was found that the size of the crystallites in the d.c. deposited films increased with increasing film thickness, while the crystallite size of r.f. deposited films remained unchanged. The d.c. deposited grains also had much stronger orientation related to the substrate than the r.f. films. XRD data indicated that the thin films with d<350 nm for r.f. and <750 nm for d.c. films have a very high degree of ZnO nonstoichiometry. This agreed well with the conductivity measurements and R(T) behaviour of the films with different resistance R. It was also found that the electrical resistivity of the samples increased exponentially with the thickness of films

  17. Optical and electrical properties of zinc oxide thin films with low resistivity via Li-N dual-acceptor doping

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Daoli, E-mail: zhang_daoli@mail.hust.edu.cn [Department of Electronic Science and Technology, Huazhong University of Science and Technology, No. 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China); Wuhan National Laboratory for Optoelectronics, 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China); Zhang Jianbing [Department of Electronic Science and Technology, Huazhong University of Science and Technology, No. 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China); Wuhan National Laboratory for Optoelectronics, 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China); Guo Zhe [Department of Electronic Science and Technology, Huazhong University of Science and Technology, No. 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China); Miao Xiangshui [Department of Electronic Science and Technology, Huazhong University of Science and Technology, No. 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China); Wuhan National Laboratory for Optoelectronics, 1037 Luoyu Road, Hongshan District, Wuhan City, Hubei Province 430074 (China)

    2011-05-19

    Highlights: > Zinc oxide films have been deposited on glass substrates by Li-N dual-acceptor doping method via a modified SILAR method. > The resistivity of ZnO film was found to be 1.04 {Omega} cm with a Hall mobility of 0.749 cm{sup 2} V{sup -1} s{sup -1}, carrier concentration of 8.02 x 1018 cm{sup -3}, and transmittance of about 80% in visible range showing good crystallinity with prior c-axis orientation. > A shallow acceptor level of 91 meV is identified from free-to-neutral-acceptor transitions. > Another deep level of 255 meV was ascribed to Li{sub Zn}-Li{sub i} complex. - Abstract: Zinc oxide thin films with low resistivity have been deposited on glass substrates by Li-N dual-acceptor doping method via a modified successive ionic layer adsorption and reaction process. The thin films were systematically characterized via scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction, ultraviolet-visible spectrophotometry and fluorescence spectrophotometry. The resistivity of zinc oxide film was found to be 1.04 {Omega} cm with a Hall mobility of 0.749 cm{sup 2} V{sup -1} s{sup -1} and carrier concentration of 8.02 x 10{sup 18} cm{sup -3}. The Li-N dual-acceptor doped zinc oxide films showed good crystallinity with prior c-axis orientation, and high transmittance of about 80% in visible range. Moreover, the effects of Li doping level and other parameters on crystallinity, electrical and ultraviolet emission of zinc oxide films were investigated.

  18. Preparation and properties of KCl-doped Cu{sub 2}O thin film by electrodeposition

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Xiaojiao, E-mail: yxjw@xaut.edu.cn [Xi’an University of Technology, Xi’an 710048 (China); Li, Xinming [Xi’an University of Technology, Xi’an 710048 (China); Zheng, Gang [Xi’an University of Technology, Xi’an 710048 (China); Northwestern Polytechnical University, Xi’an 710072 (China); Wei, Yuchen [The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Zhang, Ama; Yao, Binghua [Xi’an University of Technology, Xi’an 710048 (China)

    2013-04-01

    With the indium tin oxide-coated glass as working electrode, cuprous oxide thin film is fabricated by means of electrodeposition. The effects of KCl doped and annealing treatment upon Cu{sub 2}O thin film morphology, surface resistivity, open-circuit voltage, electric conduction types and visible light response are studied. The research results indicate that KCl doped has a great effect upon Cu{sub 2}O crystal morphology, thus, making Cu{sub 2}O thin film surface resistivity drop, and the open-circuit voltage increase and that electric conduction types are transformed from p type into n type, and the visible light (400–500 nm) absorption rate is slightly reduced. Annealing treatment can obviously decrease Cu{sub 2}O thin film surface resistivity and improve its open-circuit voltage. When KCl concentration in electrolytic solution reaches 7 mmol/L, Cu{sub 2}O thin film morphology can be changed from the dendritic crystal into the cubic crystal and Cu{sub 2}O thin film surface resistivity decreases from the initial 2.5 × 10{sup 6} Ω cm to 8.5 × 10{sup 4} Ω cm. After annealing treatment at 320 °C for 30 min, the surface resistivity decreases to 8.5 × 10{sup 2} Ω cm, and the open-circuit voltage increases from the initial 3.1 mV to 79.2 mV.

  19. Co-sputtered ZnO:Si thin films as transparent conductive oxides

    Energy Technology Data Exchange (ETDEWEB)

    Faure, C. [CNRS, Univ. Bordeaux, ICMCB, UPR 9048, F33600 Pessac (France); Clatot, J. [LRCS, 33 Rue St Leu, F-80039 Amiens (France); Teule-Gay, L.; Campet, G. [CNRS, Univ. Bordeaux, ICMCB, UPR 9048, F33600 Pessac (France); Labrugere, C. [CeCaMA, Universite de Bordeaux, ICMCB, 87 avenue du Dr. A. Schweitzer, Pessac, F-33608 (France); Nistor, M. [National Institute for Lasers, Plasmas and Radiation Physics, L22, PO Box MG-36, 77125 Bucharest-Magurele (Romania); Rougier, A., E-mail: rougier@icmcb-bordeaux.cnrs.fr [CNRS, Univ. Bordeaux, ICMCB, UPR 9048, F33600 Pessac (France)

    2012-12-01

    Silicon doped Zinc Oxide thin films, so-called SZO, were deposited at room temperature on glass and plastic substrates by co-sputtering of ZnO and SiO{sub 2} targets. The influence of the SiO{sub 2} target power supply (from 30 to 75 W) on the SZO thin film composition and crystallinity is discussed. Si/Zn atomic ratio, determined by X-ray microprobe, increases from 1.2 to 8.2 at.%. For Si/Zn ratio equal and lower than 3.9%, SZO (S{sub 3.9}ZO) thin films exhibit the Wurzite structure with the (0 0 2) preferred orientation. Larger Si content leads to a decrease in crystallinity. With Si addition, the resistivity decreases down to 3.5 Multiplication-Sign 10{sup -3} Ohm-Sign {center_dot}cm for SZO thin film containing 3.9 at.% of Si prior to an increase. The mean transmittance of S{sub 3.9}ZO thin film on glass substrate approaches 80% (it is about 90% for the film itself) in the visible range (from 400 to 750 nm). Co-sputtered SZO thin films are suitable candidates for large area transparent conductive oxides. - Highlights: Black-Right-Pointing-Pointer Si doped ZnO thin films by co-sputtering of ZnO and SiO{sub 2} targets. Black-Right-Pointing-Pointer Minimum of resistivity for Si doped ZnO thin films containing 3.9% of Si. Black-Right-Pointing-Pointer Si and O environments by X-ray Photoelectron Spectroscopy.

  20. Dendrimeric Thin-Film Composite Membranes: Free Volume, Roughness, and Fouling Resistance

    KAUST Repository

    Phuoc, Duong

    2017-11-10

    Copolyamide films with a thickness from 50 to 780 nm were fabricated by interfacial polymerization between mixtures of m-phenylene diamine and primary amine-terminated polyamidoamine dendrimers (PAMAM) in the aqueous phase and trimesoyl chloride (TMC) in the organic phase. Different PAMAM generations (G0, d = 15 Å, Z = 4; G3, d = 36 Å, Z = 32; and G5, d = 54, Z = 128, where d is the measured diameter and Z is the number of terminal groups) and concentrations were used to obtain copolyamide films with different crosslinked structures. The influences of the concentration and degree of branching (PAMAM generation) on free volume were analysed via positon annihilation spectroscopy (PAS) and correlated with the separation properties of copolyamide films. Besides, surface and intrinsic properties of copolyamide films under different conditions were compared. The high hydrophilicity of PAMAM in the copolyamide network leads to the formation of a hydration layer on the copolyamide surface, which minimizes fouling. The separation performance of copolyamide membranes with various PAMAM networks was investigated in forward osmosis (FO) experiments. Understanding the correlation between the PAMAM structure/concentration, free volume, thickness, and surface intrinsic properties leads to the design of suitable fouling resistant thin-film composite membranes in a single interfacial polymerization process.

  1. TI--CR--AL--O thin film resistors

    Science.gov (United States)

    Jankowski, Alan F.; Schmid, Anthony P.

    2000-01-01

    Thin films of Ti--Cr--Al--O are used as a resistor material. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O.sub.2. Resistivity values from 10.sup.4 to 10.sup.10 Ohm-cm have been measured for Ti--Cr--Al--O film Ti--Cr--Al--O as a thin film resistor has been found to be thermodynamically stable, unlike other metal-oxide films. The Ti--Cr--Al--O film can be used as a vertical or lateral resistor, for example, as a layer beneath a field emission cathode in a flat panel display; or used to control surface emissivity, for example, as a coating on an insulating material such as vertical wall supports in flat panel displays.

  2. Effects of bacteria on CdS thin films used in technological devices

    Science.gov (United States)

    Alpdoğan, S.; Adıgüzel, A. O.; Sahan, B.; Tunçer, M.; Metin Gubur, H.

    2017-04-01

    Cadmium sulfide (CdS) thin films were fabricated on glass substrates by the chemical bath deposition method at 70 {}^\\circ \\text{C} considering deposition times ranging from 2 h to 5 h. The optical band gaps of CdS thin films were found to be in the 2.42-2.37 eV range. CdS thin films had uniform spherical nano-size grains which had polycrystalline, hexagonal and cubic phases. The films had a characteristic electrical resistivity of the order of {{10}5} Ω \\text{cm} and n-type conductivity at room condition. CdS thin films were incubated in cultures of B.domonas aeruginosa and Staphylococcus aureus, which exist abundantly in the environment, and form biofilms. SEM images showed that S. aureus and K. pneumonia were detected significantly on the film surfaces with a few of P. aeruginosa and B. subtilis cells attached. CdS thin film surface exhibits relatively good resistance to the colonization of P. aeruginosa and B. subtilis. Optical results showed that the band gap of CdS thin films which interacted with the bacteria is 2.42 \\text{eV} . The crystal structure and electrical properties of CdS thin films were not affected by bacterial adhesion. The antimicrobial effect of CdS nanoparticles was different for different bacterial strains.

  3. Optical and electrical properties of transparent conducting B-doped ZnO thin films prepared by various deposition methods

    International Nuclear Information System (INIS)

    Nomoto, Jun-ichi; Miyata, Toshihiro; Minami, Tadatsugu

    2011-01-01

    B-doped ZnO (BZO) thin films were prepared with various thicknesses up to about 500 nm on glass substrates at 200 deg. C by dc or rf magnetron sputtering deposition, pulsed laser deposition (PLD), and vacuum arc plasma evaporation (VAPE) methods. Resistivities of 4-6 x 10 -4 Ω cm were obtained in BZO thin films prepared with a B content [B/(B + Zn) atomic ratio] around 1 at. % by PLD and VAPE methods: Hall mobilities above 40 cm 2 /Vs and carrier concentrations on the order of 10 20 cm -3 . All 500-nm-thick-BZO thin films prepared with a resistivity on the order of 10 -3 -10 -4 Ω cm exhibited an averaged transmittance above 80% in the wavelength range of 400-1100 nm. The resistivity in BZO thin films prepared with a thickness below about 500 nm was found to increase over time with exposure to various high humidity environments. In heat-resistance tests, the resistivity stability of BZO thin films was found to be nearly equal to that of Ga-doped ZnO thin films, so these films were judged suitable for use as a transparent electrode for thin-film solar cells.

  4. Enhanced dielectric and electrical properties of annealed PVDF thin film

    Science.gov (United States)

    Arshad, A. N.; Rozana, M. D.; Wahid, M. H. M.; Mahmood, M. K. A.; Sarip, M. N.; Habibah, Z.; Rusop, M.

    2018-05-01

    Poly (vinylideneflouride) (PVDF) thin films were annealed at various annealing temperatures ranging from 70°C to 170°C. This study demonstrates that PVDF thin films annealed at temperature of 70°C (AN70) showed significant enhancement in their dielectric constant (14) at frequency of 1 kHz in comparison to un-annealed PVDF (UN-PVDF), dielectric constant (10) at the same measured frequency. As the annealing temperature was increased from 90°C (AN90) to 150°C (AN150), the dielectric constant value of PVDF thin films was observed to decrease gradually to 11. AN70 also revealed low tangent loss (tan δ) value at similar frequency. With respect to its resistivity properties, the values were found to increase from 1.98×104 Ω.cm to 3.24×104 Ω.cm for AN70 and UN-PVDF films respectively. The improved in dielectric constant, with low tangent loss and high resistivity value suggests that 70°C is the favorable annealing temperature for PVDF thin films. Hence, AN70 is a promising film to be utilized for application in electronic devices such as low frequency capacitor.

  5. Maintenance and preservation of concrete structures. Report 3: Abrasion-erosion resistance of concrete

    Science.gov (United States)

    Liu, T. C.

    1980-07-01

    This report describes a laboratory test program on abrasion-erosion resistance of concrete, including the development of a new underwater abrasion-erosion test method. This program was designed to evaluate the relative abrasion-erosion resistance of various materials considered for use in the repair of erosion-damaged concrete structures. The test program encompassed three concrete types (conventional concrete, fiber-reinforced concrete, and polymer concrete); seven aggregate types (limestone, chert, trap rock, quartzite, granite, siliceous gravel, and slag); three principal water-cement rations (0.72, 0.54, and 0.40); and six types of surface treatment (vacuum, polyurethane coating, acrylic mortar coating, epoxy mortar coating, furan resin mortar coating, and iron aggregate topping). A total of 114 specimens made from 41 batches of concrete was tested. Based on the test data obtained, a comprehensive evaluation of the effects of various parameters on the abrasion-erosion resistance of concrete was presented. Materials suitable for use in the repair of erosion-damaged concrete structures were recommended. Additional work to correlate the reported findings with field performance was formulated.

  6. Influence of film thickness on structural, optical, and electrical properties of spray deposited antimony doped SnO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Abhijit A., E-mail: aay_physics@yahoo.co.in

    2015-09-30

    Transparent conducting antimony doped SnO{sub 2} thin films with varying thickness were deposited by chemical spray pyrolysis technique from non-aqueous solvent Propan-2-ol. The effect of film thickness on the properties of antimony doped SnO{sub 2} thin films have been studied. X-ray diffraction measurements showed tetragonal crystal structure of as-deposited antimony doped SnO{sub 2} films irrespective of film thickness. The surface morphology of antimony doped SnO{sub 2} thin film is spherical with the continuous distribution of grains. Electrical and optical properties were investigated by Hall Effect and optical measurements. The average optical transmittance of films decreased from 89% to 73% within the visible range (350–850 nm) with increase in film thickness. The minimum value of sheet resistance observed is 4.81 Ω/cm{sup 2}. The lowest resistivity found is 3.76 × 10{sup −4} Ω cm at 660 nm film thickness. - Highlights: • Effect of film thickness on the properties of antimony doped SnO{sub 2} thin films • Crystalline size in the range of 34–37 nm • Average transmittance decreased from 89% to 73% in the visible region. • Minimum sheet resistance of 4.81 Ω/cm{sup 2} • Lowest resistivity is found to be 3.76 × 10{sup −4} Ω cm at 660 nm film thickness.

  7. Pentiptycene-based polyurethane with enhanced mechanical properties and CO2-plasticization resistance for thin film gas separation membranes.

    Science.gov (United States)

    Pournaghshband Isfahani, Ali; Sadeghi, Morteza; Wakimoto, Kazuki; Shrestha, Binod Babu; Bagheri, Rouhollah; Sivaniah, Easan; Ghalei, Behnam

    2018-04-30

    Development of thin film composite (TFC) membranes offers an opportunity to achieve the permeability/selectivity requirements for optimum CO2 separation performance. However, the durability and performance of thin film gas separation membranes are mostly challenged by weak mechanical properties and high CO2 plasticization. Here, we designed new polyurethane (PU) structures with bulky aromatic chain extenders that afford preferred mechanical properties for ultra-thin film formation. An improvement of about 1500% in Young's modulus and 600% in hardness was observed for pentiptycene-based PUs compared to typical PU membranes. Single (CO2, H2, CH4, and N2) and mixed (CO2/N2 and CO2/CH4) gas permeability tests were performed on the PU membranes. The resulting TFC membranes showed a high CO2 permeance up to 1400 GPU (10-6 cm3(STP) cm-2s-1 cmHg-1) and the CO2/N2 and CO2/H2 selectivities of about 22 and 2.1, respectively. The enhanced mechanical properties of pentiptycene-based PUs results in high performance thin membranes with the similar selectivity of the bulk polymer. The thin film membranes prepared from pentiptycene-based PUs also showed a two-fold enhanced plasticization resistance compared to non-pentiptycene containing PU membranes.

  8. Abrasion Resistance and Mechanical Properties of Waste-Glass-Fiber-Reinforced Roller-compacted Concrete

    Science.gov (United States)

    Yildizel, S. A.; Timur, O.; Ozturk, A. U.

    2018-05-01

    The potential use of waste glass fibers in roller-compacted concrete (RCC) was investigated with the aim to improve its performance and reduce environmental effects. The research was focused on the abrasion resistance and compressive and flexural strengths of the reinforced concrete relative to those of reference mixes without fibers. The freeze-thaw resistance of RCC mixes was also examined. It was found that the use of waste glass fibers at a rate of 2 % increased the abrasion resistance of the RCC mixes considerably.

  9. Annealing effect on the bipolar resistive switching behaviors of BiFeO3 thin films on LaNiO3-buffered Si substrates

    International Nuclear Information System (INIS)

    Chen Xinman; Zhang Hu; Ruan Kaibin; Shi Wangzhou

    2012-01-01

    Highlights: ► Annealing effect on the bipolar resistive switching behaviors of BiFeO 3 thin films with Pt/BiFeO 3 /LNO was reported. ► Rectification property was explained from the asymmetrical contact between top and bottom interfaces and the distinct oxygen vacancy density. ► The modification of Schottky-like barrier was suggested to be responsible for the resistance switching behaviors of Pt/BiFeO 3 /LNO devices. - Abstract: We reported the annealing effect on the electrical behaviors of BiFeO 3 thin films integrated on LaNiO 3 (LNO) layers buffered Si substrates by sol–gel spin-coating technique. All the BiFeO 3 thin films exhibit the reversible bipolar resistive switching behaviors with Pt/BiFeO 3 /LNO configuration. The electrical conduction mechanism of the devices was dominated by the Ohmic conduction in the low resistance state and trap-controlled space charged limited current in the high resistance state. Good diode-like rectification property was observed in device with BiFeO 3 film annealed at 500 °C, but vanished in device with BiFeO 3 film annealed at 600 °C. This was attributed to the asymmetrical contact between top and bottom interfaces as well as the distinct oxygen vacancy density verified by XPS. Furthermore, the modification of Schottky-like barrier due to the drift of oxygen vacancies was suggested to be responsible for the resistance switching behaviors of Pt/BiFeO 3 /LNO devices.

  10. Large-area SnO2: F thin films by offline APCVD

    International Nuclear Information System (INIS)

    Wang, Yan; Wu, Yucheng; Qin, Yongqiang; Zhang, Zhihai; Shi, Chengwu; Zhang, Qingfeng; Li, Changhao; Xia, Xiaohong; Sun, Stanley; Chen, Leon

    2011-01-01

    Highlights: → Large-area (1245 mm x 635 mm) FTO thin films were successfully deposited by offline APCVD process. → The as-prepared FTO thin films with sheet resistance 8-11 Ω/□ and direct transmittance more than 83% exhibited better than that of the online ones. → The maximum quantum efficiency of the solar cells based on offline FTO substrate was 0.750 at wavelength 540 nm. → The power of the solar modules using the offline FTO as glass substrates was 51.639 W, higher than that of the modules based on the online ones. -- Abstract: In this paper, we reported the successful preparation of fluorine-doped tin oxide (FTO) thin films on large-area glass substrates (1245 mm x 635 mm x 3 mm) by self-designed offline atmospheric pressure chemical vapor deposition (APCVD) process. The FTO thin films were achieved through a combinatorial chemistry approach using tin tetrachloride, water and oxygen as precursors and Freon (F-152, C2H4F2) as dopant. The deposited films were characterized for crystallinity, morphology (roughness) and sheet resistance to aid optimization of materials suitable for solar cells. We got the FTO thin films with sheet resistance 8-11 Ω/□ and direct transmittance more than 83%. X-ray diffraction (XRD) characterization suggested that the as-prepared FTO films were composed of multicrystal, with the average crystal size 200-300 nm and good crystallinity. Further more, the field emission scanning electron microscope (FESEM) images showed that the films were produced with good surface morphology (haze). Selected samples were used for manufacturing tandem amorphous silicon (a-Si:H) thin film solar cells and modules by plasma enhanced chemical vapor deposition (PECVD). Compared with commercially available FTO thin films coated by online chemical vapor deposition, our FTO coatings show excellent performance resulting in a high quantum efficiency yield for a-Si:H solar cells and ideal open voltage and short circuit current for a-Si:H solar

  11. Hard Coat Layers by PE-CVD Process for the Top Surface of Touch Panel

    International Nuclear Information System (INIS)

    Okunishi, T; Sato, N; Yazawa, K

    2013-01-01

    In order to protect surface from damages, the high pencil hardness and the high abrasion resistance are required for the hard coat layers on polyethylene telephthalate (PET) films for the application of touch panel surface. We have already found that the UV-curing-hard-coat-polymer (UHP) coated PET films show the poor abrasion resistance, while they have the high pencil hardness. It reveals that the abrasion resistance of hard coat layers of the UHP is not simply dependent on the pencil hardness. In this work, we have studied to improve the abrasion resistance of SiOC films as hard coat layers, which were formed by PE-CVD process on UHP coated PET. The abrasion resistance was evaluated by Taber abrasion test. PE-CVD hard coat layers which formed on UHP coater PET films have showed the better abrasion resistance and have the possibility of substitution to the thin glass sheets for touch panel application.

  12. Low resistivity molybdenum thin film towards the back contact of dye ...

    Indian Academy of Sciences (India)

    Abstract. This paper reports the optimization of the molybdenum thin film electrode as the back contact of dye-sensitized solar cell (DSSC). The molybdenum thin film was grown on the glass substrate by direct current sputtering techniques of which the sputtering power was 150Wat 18 sccm flow rate of Ar. At such sputtering ...

  13. Corrosion resistance and biocompatibility of zirconium oxynitride thin film growth by RF sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Cubillos, G. I.; Olaya, J. J.; Clavijo, D.; Alfonso, J. E. [Universidad Nacional de Colombia, Carrera 45 No. 26-85, AA 14490 Bogota D. C. (Colombia); Bethencourt, M., E-mail: jealfonsoo@unal.edu.co [Universidad de Cadiz, Centro Andaluz de Ciencia y Tecnologia Marinas, Departamento de Ciencia de los Materiales e Ingenieria Metalurgica y Quimica Inorganica, Av. Republica de Saharaui, Puerto Real, E-11510 Cadiz (Spain)

    2012-07-01

    Thin films of zirconium oxynitride were grown on common glass, silicon (100) and stainless steel 316 L substrates using the reactive RF magnetron sputtering technique. The films were analyzed through structural, morphological and biocompatibility studies. The structural analysis was carried out using X-ray diffraction (XRD), and the morphological analysis was carried out using scanning electron microscopy (Sem) and atomic force microscopy (AFM). These studies were done as a function of growth parameters, such as power applied to the target, substrate temperature, and flow ratios. The corrosion resistance studies were made on samples of stainless steel 316 L coated and uncoated with Zr{sub x}N{sub y}O films, through of polarization curves. The studies of biocompatibility were carried out on zirconium oxynitride films deposited on stainless steel 316 L through proliferation and cellular adhesion. The XRD analysis shows that films deposited at 623 K, with a flow ratio {Phi}N{sub 2}/{Phi}O{sub 2} of 1.25 and a total deposit time of 30 minutes grew preferentially oriented along the (111) plane of the zirconium oxynitride monoclinic phase. The Sem analyses showed that the films grew homogeneously, and the AFM studies indicated that the average rugosity of the film was 5.9 nm and the average particle size was 150 nm. The analysis of the corrosion resistant, shows that the stainless steel coated with the film was increased a factor 10. Finally; through the analysis of the biocompatibility we established that the films have a better surface than the substrate (stainless steel 316 L) in terms of the adhesion and proliferation of bone cells. (Author)

  14. Tc depression and superconductor-insulator transition in molybdenum nitride thin films

    Science.gov (United States)

    Ichikawa, F.; Makise, K.; Tsuneoka, T.; Maeda, S.; Shinozaki, B.

    2018-03-01

    We have studied that the Tc depression and the superconductor-insulator transition (SIT) in molybdenum nitride (MoN) thin films. Thin films were fabricated by reactive DC magnetron sputtering method onto (100) MgO substrates in the mixture of Ar and N2 gases. Several dozen MoN thin films were prepared in the range of 3 nm < thickness d < 60 nm. The resistance was measured by a DC four-probe technique. It is found that Tc decreases from 6.6 K for thick films with increase of the normal state sheet resistance {R}{{sq}}{{N}} and experimental data were fitted to the Finkel’stein formula using the bulk superconducting transition temperature Tc 0 = 6.45 K and the elastic scattering time of electron τ = 1.6 × 10‑16 s. From this analysis the critical sheet resistance Rc is found about 2 kΩ, which is smaller than the quantum sheet resistance R Q. This value of Rc is almost the same as those for 2D NbN films. The value of τ for MoN films is also the similar value for NbN films 1.0 × 10‑16 s, while Tc 0 is different from that for NbN films 14.85 K. It is indicated that the mechanism of SIT for MoN films is similar to that of NbN films, while the mean free path ℓ for MoN films is larger than that for NbN films.

  15. Prediction of crack density and electrical resistance changes in indium tin oxide/polymer thin films under tensile loading

    KAUST Repository

    Mora Cordova, Angel; Khan, Kamran; El Sayed, Tamer

    2014-01-01

    We present unified predictions for the crack onset strain, evolution of crack density, and changes in electrical resistance in indium tin oxide/polymer thin films under tensile loading. We propose a damage mechanics model to quantify and predict

  16. Laser nanostructuring of ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Nedyalkov, N., E-mail: nned@ie.bas.bg [Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi Kohoku-ku, Yokohama-shi, Kanagawa-ken 223-8522 (Japan); Institute of Electronics, Bulgarian Academy of Sciences, Tzarigradsko shousse 72, Sofia 1784 (Bulgaria); Koleva, M.; Nikov, R.; Atanasov, P. [Institute of Electronics, Bulgarian Academy of Sciences, Tzarigradsko shousse 72, Sofia 1784 (Bulgaria); Nakajima, Y.; Takami, A.; Shibata, A.; Terakawa, M. [Department of Electronics and Electrical Engineering, Keio University, 3-14-1 Hiyoshi Kohoku-ku, Yokohama-shi, Kanagawa-ken 223-8522 (Japan)

    2016-06-30

    Highlights: • Nanosecond laser pulse nanostructuring of ZnO thin films on metal substrate is demonstrated. • Two regimes of the thin film modification are observed depending on the applied laser fluence. • At high fluence regime the ZnO film is homogeneously decomposed into nanosized particles. • The characteristic size of the formed nanostructures corresponds to the domain size of the thin film. - Abstract: In this work, results on laser processing of thin zinc oxide films deposited on metal substrate are presented. ZnO films are obtained by classical nanosecond pulsed laser deposition method in oxygen atmosphere on tantalum substrate. The produced films are then processed by nanosecond laser pulses at wavelength of 355 nm. The laser processing parameters and the film thickness are varied and their influence on the fabricated structures is estimated. The film morphology after the laser treatment is found to depend strongly on the laser fluence as two regimes are defined. It is shown that at certain conditions (high fluence regime) the laser treatment of the film leads to formation of a discrete nanostructure, composed of spherical like nanoparticles with narrow size distribution. The dynamics of the melt film on the substrate and fast cooling are found to be the main mechanisms for fabrication of the observed structures. The demonstrated method is an alternative way for direct fabrication of ZnO nanostructures on metal which can be easy implemented in applications as resistive sensor devices, electroluminescent elements, solar cell technology.

  17. Conduction noise absorption by ITO thin films attached to microstrip line utilizing Ohmic loss

    International Nuclear Information System (INIS)

    Kim, Sun-Hong; Kim, Sung-Soo

    2010-01-01

    For the aim of wide-band noise absorbers with a special design for low frequency performance, this study proposes conductive indium-tin oxide (ITO) thin films as the absorbent materials in microstrip line. ITO thin films were deposited on the polyimide film substrates by rf magnetron cosputtering of In 2 O 3 and Sn targets. The deposited ITO films show a typical value of electrical resistivity (∼10 -4 Ω m) and sheet resistance can be controlled in the range of 20-230 Ω by variation in film thickness. Microstrip line with characteristic impedance of 50 Ω was used for determining their noise absorbing properties. It is found that there is an optimum sheet resistance of ITO films for the maximum power absorption. Reflection parameter (S 11 ) is increased with decrease in sheet resistance due to impedance mismatch. On the while, transmission parameter (S 21 ) is decreased with decrease in sheet resistance due to larger Ohmic loss of the ITO films. Experimental results and computational prediction show that the optimum sheet resistance is about 100 Ω. For this film, greater power absorption is predicted in the lower frequency region than ferrite thin films of high magnetic loss, which indicates that Ohmic loss is the predominant loss parameter for power absorption in the low frequency range.

  18. Ag/PEPC/NiPc/ZnO/Ag thin film capacitive and resistive humidity sensors

    International Nuclear Information System (INIS)

    Karimov, Kh. S.; Saleem, M.; Murtaza, Imran; Farooq, M.; Cheong, Kuan Yew; Noor, Ahmad Fauzi Mohd

    2010-01-01

    A thin film of blended poly-N-epoxypropylcarbazole (PEPC) (25 wt.%), nickel phthalocyanine (NiPc) (50 wt.%) and ZnO nano-powder (25 wt.%) in benzene (5 wt.%) was spin-coated on a glass substrate with silver electrodes to produce a surface-type Ag/PEPC/NiPc/ZnO/Ag capacitive and resistive sensor. Sensors with two different PEPC/NiPc/ZnO film thicknesses (330 and 400 nm) were fabricated and compared. The effects of humidity on capacitance and resistance of the Ag/PEPC/NiPc/ZnO/Ag sensors were investigated at two frequencies of the applied voltage: 120 Hz and 1 kHz. It was observed that at 120 Hz under humidity of up to 95% RH the capacitance of the sensors increased by 540 times and resistance decreased by 450 times with respect to humidity conditions of 50% RH. It was found that the sensor with a thinner semiconducting film (330 nm) was more sensitive than the sensor with a thicker film (400 nm). The sensitivity was improved when the sensor was used at a lower frequency as compared with a high frequency. It is assumed that the humidity response of the sensors is associated with absorption of water vapors and doping of water molecules in the semiconductor blend layer. This had been proven by simulation of the capacitance-humidity relationship. (semiconductor devices)

  19. An investigation of room temperature ''oxidized'' thin films of A1 for photovoltaic applications

    International Nuclear Information System (INIS)

    Adegboyega, G.A.

    1985-12-01

    Sheet resistance and transmittance changes of thin films of A1 evaporated in high vacuum were measured during sorption of oxygen at room atmosphere. An increase of both sheet resistance and transmittance with a tendency to saturation has been observed. Evaluation of various thicknesses of the films for possible use as transparent electrode material for photovoltaic applications shows that for very thin films ( = 200 A) the ''oxidized'' films are superior. (author)

  20. Contact Resistance Reduction of ZnO Thin Film Transistors (TFTs) with Saw-Shaped Electrode

    KAUST Repository

    Park, Woojin

    2018-05-15

    We report a saw-shaped electrode architecture ZnO thin film transistor (TFT) for effectively increase channel width. Such a saw-shaped electrode has ~2 times longer contact line at the contact metal/ZnO channel junction. We experimentally observed an enhancement in the output drive current by 50% and reduction in the contact resistance by over 50%, when compared to a typical shaped electrode ZnO TFT consuming the same chip area. This performance enhancement is attributed to extension of channel width. This technique can contribute to device performance enhancement and especially reduction in the contact resistance which is a serious challenge.

  1. Solid thin film materials for use in thin film charge-coupled devices

    International Nuclear Information System (INIS)

    Lynch, S.J.

    1983-01-01

    Solid thin films deposited by vacuum deposition were evaluated to ascertain their effectiveness for use in the manufacturing of charge-coupled devices (CCDs). Optical and electrical characteristics of tellurium and Bi 2 Te 3 solid thin films were obtained in order to design and to simulate successfully the operation of thin film (TF) CCDs. In this article some of the material differences between single-crystal material and the island-structured thin film used in TFCCDs are discussed. The electrical parameters were obtained and tabulated, e.g. the mobility, conductivity, dielectric constants, permittivity, lifetime of holes and electrons in the thin films and drift diffusion constants. The optical parameters were also measured and analyzed. After the design was complete, experimental TFCCDs were manufactured and were successfully operated utilizing the aforementioned solid thin films. (Auth.)

  2. Final Technical Report: Development of an Abrasion-Resistant Antisoiling Coating for Front-Surface Reflectors

    Energy Technology Data Exchange (ETDEWEB)

    Gee, Randy C. [Sundog Solar Technology, Arvada, CO (United States)

    2017-07-18

    A high-performance reflective film has been successfully developed for Concentrating Solar Power (CSP) solar concentrators. Anti-soiling properties and abrasion resistance have been incorporated into the reflector to reduce reflector cleaning costs and to enhance durability. This approach has also resulted in higher reflectance and improved specularity. From the outset of this project we focused on the use of established high-volume roll-to-roll manufacturing techniques to achieve low manufacturing costs on a per ubit area basis. Roll-to-roll manufacturng equipment has a high capital cost so there is an entire industry devoted to roll-to-roll “toll” manufacturing, where the equipment is operated “around the clock” to produce a multitude of products for a large variety of uses. Using this approach, the reflective film can be manufactured by toll coaters/converters on an as-needed basis.

  3. Optical and electrical properties of transparent conducting B-doped ZnO thin films prepared by various deposition methods

    Energy Technology Data Exchange (ETDEWEB)

    Nomoto, Jun-ichi; Miyata, Toshihiro; Minami, Tadatsugu [Optoelectronic Device System R and D Center, Kanazawa Institute of Technology, 7-1 Ohgigaoka, Nonoichi, Ishikawa 921-8501 (Japan)

    2011-07-15

    B-doped ZnO (BZO) thin films were prepared with various thicknesses up to about 500 nm on glass substrates at 200 deg. C by dc or rf magnetron sputtering deposition, pulsed laser deposition (PLD), and vacuum arc plasma evaporation (VAPE) methods. Resistivities of 4-6 x 10{sup -4}{Omega} cm were obtained in BZO thin films prepared with a B content [B/(B + Zn) atomic ratio] around 1 at. % by PLD and VAPE methods: Hall mobilities above 40 cm{sup 2}/Vs and carrier concentrations on the order of 10{sup 20} cm{sup -3}. All 500-nm-thick-BZO thin films prepared with a resistivity on the order of 10{sup -3}-10{sup -4}{Omega} cm exhibited an averaged transmittance above 80% in the wavelength range of 400-1100 nm. The resistivity in BZO thin films prepared with a thickness below about 500 nm was found to increase over time with exposure to various high humidity environments. In heat-resistance tests, the resistivity stability of BZO thin films was found to be nearly equal to that of Ga-doped ZnO thin films, so these films were judged suitable for use as a transparent electrode for thin-film solar cells.

  4. Development of wear resistant zirconium oxide thin films on stainless steel substrates

    International Nuclear Information System (INIS)

    Then, I.K.; Mujahid, M.; Zhang, B.

    2005-01-01

    The present work deals specifically with the development of zirconium oxide thin film coatings on the stainless steel orthodontic bracket system by sputtering technique. Thin films of zirconium oxide have been deposited on injection molded stainless steel substrates using sputtering under controlled temperature and environment conditions. The deposited films, 1.5 μm in thickness, were found to have a predominantly tetragonal structure with grain size of about 5 nm. The grain size was found to increase only slightly with increasing heat treatment time at 650 C. It has been shown that thin-film zirconia coatings with stable structure and good adhesion along with very low friction coefficient could be produced. (orig.)

  5. Development of wear resistant zirconium oxide thin films on stainless steel substrates

    Energy Technology Data Exchange (ETDEWEB)

    Then, I.K.; Mujahid, M. [School of Materials Engineering, Nanyang Technological Univ. (Singapore); Zhang, B. [Dou Yee Technologies Pte Ltd, Bedok Industrial Park C (Singapore)

    2005-07-01

    The present work deals specifically with the development of zirconium oxide thin film coatings on the stainless steel orthodontic bracket system by sputtering technique. Thin films of zirconium oxide have been deposited on injection molded stainless steel substrates using sputtering under controlled temperature and environment conditions. The deposited films, 1.5 {mu}m in thickness, were found to have a predominantly tetragonal structure with grain size of about 5 nm. The grain size was found to increase only slightly with increasing heat treatment time at 650 C. It has been shown that thin-film zirconia coatings with stable structure and good adhesion along with very low friction coefficient could be produced. (orig.)

  6. Transparent and conductive electrodes by large-scale nano-structuring of noble metal thin-films

    DEFF Research Database (Denmark)

    Linnet, Jes; Runge Walther, Anders; Wolff, Christian

    2018-01-01

    grid, and nano-wire thin-films. The indium and carbon films do not match the chemical stability nor the electrical performance of the noble metals, and many metal films are not uniform in material distribution leading to significant surface roughness and randomized transmission haze. We demonstrate...... solution-processed masks for physical vapor-deposited metal electrodes consisting of hexagonally ordered aperture arrays with scalable aperture-size and spacing in an otherwise homogeneous noble metal thin-film that may exhibit better electrical performance than carbon nanotube-based thin-films...... for equivalent optical transparency. The fabricated electrodes are characterized optically and electrically by measuring transmittance and sheet resistance. The presented methods yield large-scale reproducible results. Experimentally realized thin-films with very low sheet resistance, Rsh = 2.01 ± 0.14 Ω...

  7. Thin-film photovoltaic technology

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, R.N. [National Renewable Energy Laboratory, Golden, CO (United States)

    2010-07-01

    The high material and processing costs associated with single-crystal and polycrystalline silicon wafers that are commonly used in photovoltaic cells render these modules expensive. This presentation described thin-film solar cell technology as a promising alternative to silicon solar cell technology. Cadmium telluride (CdTe) thin films along with copper, indium, gallium, and selenium (CIGS) thin films have become the leaders in this field. Their large optical absorption coefficient can be attributed to a direct energy gap that allows the use of thin layers (1-2 {mu}m) of active material. The efficiency of thin-film solar cell devices based on CIGS is 20 per cent, compared to 16.7 per cent for thin-film solar cell devices based on CdTe. IBM recently reported an efficiency of 9.7 per cent for a new type of inorganic thin-film solar cell based on a Cu{sub 2}ZnSn(S, Se){sub 4} compound. The efficiency of an organic thin-film solar cell is 7.9 per cent. This presentation included a graph of PV device efficiencies and discussed technological advances in non-vacuum deposited, CIGS-based thin-film solar cells. 1 fig.

  8. Reliability growth of thin film resistors contact

    Directory of Open Access Journals (Sweden)

    Lugin A. N.

    2010-10-01

    Full Text Available Necessity of resistive layer growth under the contact and in the contact zone of resistive element is shown in order to reduce peak values of current flow and power dissipation in the contact of thin film resistor, thereby to increase the resistor stability to parametric and catastrophic failures.

  9. Plasmon Enhancement of Photoinduced Resistivity Changes in Bi1-xCaxMnO3 Thin Films

    Science.gov (United States)

    Smolyaninova, Vera; Talanova, E.; Kolagani, Rajeswari; Yong, G.; Kennedy, R.; Steger, M.; Wall, K.

    2007-03-01

    Doped rare-earth manganese oxides (manganites) exhibit a wide variety of physical phenomena due to complex interplay of electronic, magnetic, orbital, and structural degrees of freedom and their sensitivity to external fields. A photoinduced insulator to conductor transition in charge-ordered manganites is especially interesting from the point of view of creating photonic devices. Thin films of Bi0.4Ca0.6MnO3 exhibit large photoinduced resistivity changes associated with melting of the charge ordering by visible light [1]. We have found a considerable increase of the photoinduced resistivity changes in the Bi0.4Ca0.6MnO3 thin film after depositing metal nanoparticles on the surface. This increase can be explained by enhancement of local electromagnetic field in the vicinity of the gold nanoparticle due to the plasmon resonance. The changes in lifetime of the photoinduced state will be reported, and the possible origin of these effects will be discussed. [1] V. N. Smolyaninova at al., Appl. Phys. Lett. 86, 071922 (2005).

  10. Abrasion Resistance of Nano Silica Modified Roller Compacted Rubbercrete: Cantabro Loss Method and Response Surface Methodology Approach

    Science.gov (United States)

    Adamu, Musa; Mohammed, Bashar S.; Shafiq, Nasir

    2018-04-01

    Roller compacted concrete (RCC) when used for pavement is subjected to skidding/rubbing by wheels of moving vehicles, this causes pavement surface to wear out and abrade. Therefore, abrasion resistance is one of the most important properties of concern for RCC pavement. In this study, response surface methodology was used to design, evaluate and analyze the effect of partial replacement of fine aggregate with crumb rubber, and addition of nano silica on the abrasion resistance of roller compacted rubbercrete (RCR). RCR is the terminology used for RCC pavement where crumb rubber was used as partial replacement to fine aggregate. The Box-Behnken design method was used to develop the mixtures combinations using 10%, 20%, and 30% crumb rubber with 0%, 1%, and 2% nano silica. The Cantabro loss method was used to measure the abrasion resistance. The results showed that the abrasion resistance of RCR decreases with increase in crumb rubber content, and increases with increase in addition of nano silica. The analysis of variance shows that the model developed using response surface methodology (RSM) has a very good degree of correlation, and can be used to predict the abrasion resistance of RCR with a percentage error of 5.44%. The combination of 10.76% crumb rubber and 1.59% nano silica yielded the best combinations of RCR in terms of abrasion resistance of RCR.

  11. Thin film processes II

    CERN Document Server

    Kern, Werner

    1991-01-01

    This sequel to the 1978 classic, Thin Film Processes, gives a clear, practical exposition of important thin film deposition and etching processes that have not yet been adequately reviewed. It discusses selected processes in tutorial overviews with implementation guide lines and an introduction to the literature. Though edited to stand alone, when taken together, Thin Film Processes II and its predecessor present a thorough grounding in modern thin film techniques.Key Features* Provides an all-new sequel to the 1978 classic, Thin Film Processes* Introduces new topics, and sever

  12. Abrasive Wear Resistance of the Iron- and WC-based Hardfaced Coatings Evaluated with Scratch Test Method

    Directory of Open Access Journals (Sweden)

    A. Vencl

    2013-06-01

    Full Text Available Abrasive wear is one of the most common types of wear, which makesabrasive wear resistance very important in many industries. Thehard facing is considered as useful and economical way to improve theperformance of components submitted to severe abrasive wear conditions, with wide range of applicable filler materials. The abrasive wear resistance of the three different hardfaced coatings (two iron‐based and one WC‐based, which were intended to be used for reparation of the impact plates of the ventilation mill, was investigated and compared. Abrasive wear tests were carried‐out by using the scratch tester under the dry conditions. Three normal loads of 10, 50 and 100 N and the constant sliding speed of 4 mm/s were used. Scratch test was chosen as a relatively easy and quick test method. Wear mechanism analysis showed significant influence of the hardfaced coatings structure, which, along with hardness, has determined coatings abrasive wear resistance.

  13. Effect of Ag doping on opto-electrical properties of CdS thin films for solar cell applications

    International Nuclear Information System (INIS)

    Nazir, Adnan; Toma, Andrea; Shah, Nazar Abbas; Panaro, Simone; Butt, Sajid; Sagar, Rizwan ur Rehman; Raja, Waseem; Rasool, Kamran; Maqsood, Asghari

    2014-01-01

    Highlights: • Polycrystalline CdS thin films are fabricated by means of Close Spaced Sublimation technique. • Ag is doped by simple ion-exchange technique in order to reduce resistivity of CdS thin films. • Remarkable reduction in resistivity without introducing many transparency losses. - Abstract: Cadmium sulfide (CdS) polycrystalline thin films of different thicknesses (ranging from 370 nm to 750 nm) were fabricated on corning glass substrates using Close Spaced Sublimation (CSS) technique. Optical and electrical investigation revealed that CdS thin films show an appreciable transparency (50–70% transmission) in visible range and a highly resistive behavior (10 6 Ω cm). Samples were doped by silver (Ag) at different concentrations, using ion exchange technique, in order to reduce the resistivity of CdS thin films and to improve their efficiency as a window layer for solar cell application. The doping of Ag in pure CdS thin films resulted into an increase of surface roughness and a decrease both in electrical resistivity and in transparency. By optimizing annealing parameters, we were able to properly control the optical properties of the present system. In fact, the Ag doping of pure CdS films has led to a decrease of the sample resistivity by three orders of magnitude (10 3 Ω cm) against a 20% cut in optical transmission

  14. In and Ga Codoped ZnO Film as a Front Electrode for Thin Film Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    Duy Phong Pham

    2014-01-01

    Full Text Available Doped ZnO thin films have attracted much attention in the research community as front-contact transparent conducting electrodes in thin film silicon solar cells. The prerequisite in both low resistivity and high transmittance in visible and near-infrared region for hydrogenated microcrystalline or amorphous/microcrystalline tandem thin film silicon solar cells has promoted further improvements of this material. In this work, we propose the combination of major Ga and minor In impurities codoped in ZnO film (IGZO to improve the film optoelectronic properties. A wide range of Ga and In contents in sputtering targets was explored to find optimum optical and electrical properties of deposited films. The results show that an appropriate combination of In and Ga atoms in ZnO material, followed by in-air thermal annealing process, can enhance the crystallization, conductivity, and transmittance of IGZO thin films, which can be well used as front-contact electrodes in thin film silicon solar cells.

  15. A novel design of submicron thin film point contacts

    International Nuclear Information System (INIS)

    Koch, H.

    1986-01-01

    A thin film point contact design applicable to SIS-, SNS-, and microbridge-type Josephson junctions is presented, which offers potentially advanced junction characteristics (low capacitance, low stray inductance, increased quasi-particle resistance). The design philosophy is based on the fact that a point contact results if two planes having a common symmetry axis but oriented perpendicular to each other are brought into contact with each other. For the case of thin films, instead of two-dimensional planes, the cross section of the resulting ''point''-contact is defined by the thicknesses of the two thin films. Film thicknesses can be controlled much more precisely than lateral dimensions created by lithography. Hence, submicron junction geometries can be achieved using only conventional fabrication techniques. Following this idea, Josephson weak links of the ultrashort microbridge-type have been fabricated by an all-Nb technique having a 0.3-μm X 0.2-μm cross section with a R /SUB q/ I /SUB c/ product (R /SUB q/ = quasiparticle resistance, I /SUB c/ = critical current) of more than 20 mV

  16. Characterization of thin films with synchrotron radiation in SPring-8

    International Nuclear Information System (INIS)

    Komiya, Satoshi

    2005-01-01

    Many studies about thin films by using synchrotron radiation in SPring-8 were reviewed. Structural analyses and assessment of thin films used for electronics, and also assessment of insulating films for the gate used in LSI were carried out. Film thickness, unevenness, and density of SiO 2 films in order of nanomer thickness were determined by interference fringes of x-ray reflection curves. The interface structure of (SiO 2 /Si) films was studied by x-ray crystal truncation rod scattering, and the correlation between leakage character depending on nitrogen concentration and interface structure was clarified on SiON film. The oxygen concentration in HfO films in nanometer thickness was determined by x-ray fluorescence analysis, and the interface reaction for HfO 2 /SiO 2 was clearly observed by electron spectroscopy. The structure of amorphous thin films with large dielectric constant was analyzed by x-ray absorption fine structure (XAFS) spectrum. Devices fabricated from multi-layer films showing giant magnetic resistance were developed for hard disk with a large memory. The character of giant magnetic resistance was governed by multi-layer thin film structure piled up by magnetic and nonmagnetic polycrystalline thin metals. For the multi-layer structure, the concentration distribution of constituent elements was determined to the direction of film thickness by x-ray reflection analysis and grazing incident x-ray fluorescence analysis. In the semiconductor laser source, Ga 1-x In x N, used for DVD, the local structure around In ions was studied by XAFS since constituent instability, especially overpopulation of In element, caused the deterioration of lifetime and light emission of the laser. The lattice constant of the light emission layer in InGaAs was measured by x-ray micro-beams. (author)

  17. Thin film microelectrodes for electrochemical detection of neurotransmitters

    DEFF Research Database (Denmark)

    Larsen, Simon Tylsgaard

    An important signaling process in the nervous system is the release of chemical messengers called neurotransmitters from neurons. In this thesis alternative thin film electrode materials for applications targeting electrochemical detection of neurotransmitters in chip devices were evaluated...... and conductive polymer microelectrodes made of Pedot:Pss were also fabricated and used successfully to measure transmitter release from cells. The use of different thin film electrodes for low-noise amperometric measurements of single events of transmitter release from neuronal cells was studied....... For this application a very low current noise is needed together with a large temporal resolution. It was shown, that resistive and capacitive properties of thin film electrode materials are determining their usefulness in low-noise amperometric measurements. An analytical expression for the noise was derived...

  18. Optical and Electrical Properties of the Different Magnetron Sputter Power 300°C Deposited -ZnO Thin Films and Applications in p-i-n -Si:H Thin-Film Solar Cells

    Directory of Open Access Journals (Sweden)

    Fang-Hsing Wang

    2013-01-01

    Full Text Available A compound of ZnO with 3 wt% Ga2O3 (ZnO : Ga2O3 = 97 : 3 in wt%, GZO was sintered at C as a target. The GZO thin films were deposited on glass using a radio frequency magnetron sputtering system at C by changing the deposition power from 50 W to 150 W. The effects of deposition power on the crystallization size, lattice constant (c, resistivity, carrier concentration, carrier mobility, and optical transmission rate of the GZO thin films were studied. The blue shift in the transmission spectrum of the GZO thin films was found to change with the variations of the carrier concentration because of the Burstein-Moss shifting effect. The variations in the optical band gap ( value of the GZO thin films were evaluated from the plots of , revealing that the measured value decreased with increasing deposition power. As compared with the results deposited at room temperature by Gong et al., (2010 the C deposited GZO thin films had apparent blue shift in the transmission spectrum and larger value. For the deposited GZO thin films, both the carrier concentration and mobility linearly decreased and the resistivity linearly increased with increasing deposition power. The prepared GZO thin films were also used as transparent electrodes to fabricate the amorphous silicon thin-film solar cells, and their properties were also measured.

  19. Resistivity and Hall voltage in gold thin films deposited on mica at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Bahamondes, Sebastián; Donoso, Sebastián; Ibañez-Landeta, Antonio; Flores, Marcos [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Av. Blanco Encalada 2008, Santiago (Chile); Henriquez, Ricardo, E-mail: ricardo.henriquez@usm.cl [Departamento de Física, Universidad Técnica Federico Santa María, Av. España 1680, Valparaiso 2390123 (Chile)

    2015-03-30

    Highlights: • We determined the 4 K thickness dependence of resistivity for a family of gold thin films. • We determined the thickness dependence of resistivity during the growth process. • Both behaviors are well represented by the Mayadas–Shatzkes theory. • We determined Hall tangent and Hall resistance at 4 K and up to 4.5 T. • Hall mobility is always higher than the drift mobility. - Abstract: We report the thickness dependence of the resistivity measured at 4 K of gold films grown onto mica at room temperature (RT), for thickness ranging from 8 to 100 nm. This dependence was compared to the one obtained for a sample during its growth process at RT. Both behaviors are well represented by the Mayadas–Shatzkes theory. Using this model, we found comparable contributions of electron surface and electron grain boundary scattering to the resistivity at 4 K. Hall effect measurements were performed using a variable transverse magnetic field up to 4.5 T. Hall tangent and Hall resistance exhibit a linear dependence on the magnetic field. For this magnetic field range, the Hall mobility is always larger than the drift mobility. This result is explained through the presence of the above-mentioned scattering mechanisms acting on the galvanomagnetic coefficients. In addition, we report the temperature dependence of the resistivity between 4 and 70 K.

  20. Increase of the electrical resistance of thin copper film due to 14 MeV neutron irradiation

    International Nuclear Information System (INIS)

    Agrawal, S.K.; Kumar, U.; Nigam, A.K.; Singh, S.P.

    1981-01-01

    The variation in the electrical resistance of thin copper film (500 A 0 thick), grown on the glass slide has been measured with increasing 14 MeV neutron irradiation time. The electrical resistance vs irradiation time curve shows an interesting behaviour after an irradiation of 40 minutes. However, there is a net increase in the electrical resistance with increasing neutron dose. The maximum increase in the observed electrical resistance after an irradiation of 115 mins, is 4.45%. The microstructural studies of irradiated film were made using TEM and TED techniques. The TEM patterns up to an irradiation time of 1.00 hr do not show any appreciable change in the microstructure. The TED patterns also do not show any appreciable change in the diffraction pattern up to an irradiation time of 1.0 hr. But after an irradiation time of 1.5 hrs, two extra rings appear in the TED pattern which disappear with increasing neutron irradiation time

  1. Micro-Abrasion Wear Resistance of Borided 316L Stainless Steel and AISI 1018 Steel

    Science.gov (United States)

    Reséndiz-Calderon, C. D.; Rodríguez-Castro, G. A.; Meneses-Amador, A.; Campos-Silva, I. E.; Andraca-Adame, J.; Palomar-Pardavé, M. E.; Gallardo-Hernández, E. A.

    2017-11-01

    The 316L stainless steel has high corrosion resistance but low tribological performance. In different industrial sectors (biomedical, chemical, petrochemical, and nuclear engineering), improvement upon wear resistance of 316L stainless steel components using accessible and inexpensive methods is critical. The AISI 1018 steel is widely used in industry, but its tribological performance is not the best among steels. Therefore, in this study the behavior of the borided 316L stainless steel and 1018 steel is evaluated under micro-abrasion wear. The boriding was carried out at 1223 K over 6 h of exposure time, resulting in a biphase layer composed of FeB/Fe2B phases. In order to evaluate Fe2B phase with no influence from FeB phase, AISI 1018 steel samples were borided at 1273 K for over 20 min and then diffusion annealed at 1273 K over 2 h to obtain a Fe2B mono-phase layer. Micro-abrasion wear resistance was evaluated by a commercial micro-abrasion testing rig using a mix of F-1200 SiC particles with deionized water as abrasive slurry. The obtained wear rates for FeB and Fe2B phases and for the 316L stainless steel were compared. Wear resistance of 316L stainless steel increases after boriding. The wear mechanisms for both phases and for the stainless steel were identified. Also, transient conditions for rolling and grooving abrasion were determined for the FeB and Fe2B phases.

  2. Electrical and optical properties of spray - deposited CdSe thin films

    International Nuclear Information System (INIS)

    Bedir, M.; Oeztas, M.; Bakkaloglu, O. F.

    2002-01-01

    The CdSe thin films were developed by using spray-deposition technique at different substrate temperatures of 380C, 400C and, 420C on the glass substrate. All spraying processes involved CdCI 2 (0.05 moles/liter) and SeO 2 (0.05 moles/liter ) and were carried out in atmospheric condition. The CdSe thin film samples were characterized using x-ray diffractometer and optical absorption measurements. The electrical properties of the thin film samples were investigated via Wander Pauw method. XRD patterns indicated that the CdSe thin film samples have a hexagonal structure. The direct band gap of the CdSe thin film samples were determined from optical absorption and spectral response measurements of 1.76 eV. The resistivity of the CdSe thin film samples were found to vary in the range from 5.8x10''5 to 7.32x10''5 Ωcm depending to the substrate temperature

  3. Readdressing the issue of low-temperature resistivity minimum in La{sub 0.7}Ca{sub 0.3}MnO{sub 3} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Sagdeo, P.R. [Indian Institute of Technology Indore, Indore (India); Sagdeo, Archna [Raja Ramanna Centre for Advanced Technology, Indore (India)

    2013-11-15

    We have investigated the origin of low-temperature resistivity minima observed in epitaxial thin films of La{sub 0.7}Ca{sub 0.3}MnO{sub 3} (thicknesses - 300 Aa and 3000 Aa) using electrical and magneto-transport property measurements. We observe considerably smaller hysteresis in the magnetoresistance measurements for the thicker film than the thinner film. 300 Aa film shows meta-stability in the resistivity measurements at low temperature and for this film the sample current 'I' shows large effect on the resistivity and its minima temperature. These observations suggest that the strain induces electronic intra grain inhomogeneity in these samples and these inhomogeneities consist of regions of different resistive phases. It appears that the high resistive phase prevents the transport of charge carriers between two low resistive regions thus giving rise to the resistivity minimum in these samples. (orig.)

  4. Nanomechanical investigation of thin-film electroceramic/metal-organic framework multilayers

    Science.gov (United States)

    Best, James P.; Michler, Johann; Liu, Jianxi; Wang, Zhengbang; Tsotsalas, Manuel; Maeder, Xavier; Röse, Silvana; Oberst, Vanessa; Liu, Jinxuan; Walheim, Stefan; Gliemann, Hartmut; Weidler, Peter G.; Redel, Engelbert; Wöll, Christof

    2015-09-01

    Thin-film multilayer stacks of mechanically hard magnetron sputtered indium tin oxide (ITO) and mechanically soft highly porous surface anchored metal-organic framework (SURMOF) HKUST-1 were studied using nanoindentation. Crystalline, continuous, and monolithic surface anchored MOF thin films were fabricated using a liquid-phase epitaxial growth method. Control over respective fabrication processes allowed for tuning of the thickness of the thin film systems with a high degree of precision. It was found that the mechanical indentation of such thin films is significantly affected by the substrate properties; however, elastic parameters were able to be decoupled for constituent thin-film materials (EITO ≈ 96.7 GPa, EHKUST-1 ≈ 22.0 GPa). For indentation of multilayer stacks, it was found that as the layer thicknesses were increased, while holding the relative thickness of ITO and HKUST-1 constant, the resistance to deformation was significantly altered. Such an observation is likely due to small, albeit significant, changes in film texture, interfacial roughness, size effects, and controlling deformation mechanism as a result of increasing material deposition during processing. Such effects may have consequences regarding the rational mechanical design and utilization of MOF-based hybrid thin-film devices.

  5. Mesoscale simulations of confined Nafion thin films

    Science.gov (United States)

    Vanya, P.; Sharman, J.; Elliott, J. A.

    2017-12-01

    The morphology and transport properties of thin films of the ionomer Nafion, with thicknesses on the order of the bulk cluster size, have been investigated as a model system to explain the anomalous behaviour of catalyst/electrode-polymer interfaces in membrane electrode assemblies. We have employed dissipative particle dynamics (DPD) to investigate the interaction of water and fluorocarbon chains, with carbon and quartz as confining materials, for a wide range of operational water contents and film thicknesses. We found confinement-induced clustering of water perpendicular to the thin film. Hydrophobic carbon forms a water depletion zone near the film interface, whereas hydrophilic quartz results in a zone with excess water. There are, on average, oscillating water-rich and fluorocarbon-rich regions, in agreement with experimental results from neutron reflectometry. Water diffusivity shows increasing directional anisotropy of up to 30% with decreasing film thickness, depending on the hydrophilicity of the confining material. A percolation analysis revealed significant differences in water clustering and connectivity with the confining material. These findings indicate the fundamentally different nature of ionomer thin films, compared to membranes, and suggest explanations for increased ionic resistances observed in the catalyst layer.

  6. Polarity-dependent resistance switching in GeSbTe phase-change thin films : The importance of excess Sb in filament formation

    NARCIS (Netherlands)

    Pandian, Ramanathaswamy; Kooi, Bart J.; Oosthoek, Jasper L. M.; van den Dool, Pim; Palasantzas, George; Pauza, Andrew

    2009-01-01

    We show that polarity-dependent resistance switching in GeSbTe thin films depends strongly on Sb composition by comparing current-voltage characteristics in Sb-excess Ge(2)Sb(2+x)Te(5) and stoichiometric Ge(2)Sb(2)Te(5) samples. This type of switching in Ge(2)Sb(2+x)Te(5) films is reversible with

  7. Phase Competition Induced Bio-Electrochemical Resistance and Bio-Compatibility Effect in Nanocrystalline Zr x -Cu100-x Thin Films.

    Science.gov (United States)

    Badhirappan, Geetha Priyadarshini; Nallasivam, Vignesh; Varadarajan, Madhuri; Leobeemrao, Vasantha Priya; Bose, Sivakumar; Venugopal, Elakkiya; Rajendran, Selvakumar; Angleo, Peter Chrysologue

    2018-07-01

    Nano-crystalline Zrx-Cu100-x (x = 20-100 at.%) thin films with thickness ranging from 50 to 185 nm were deposited by magnetron co-sputtering with individual Zr and Cu targets. The as-sputtered thin films were characterized by Field Emission Scanning Electron Microscope (FE-SEM), Atomic Force Microscopy (AFM) and Glancing Incidence X-ray Diffraction (GIXRD) for structural and morphological properties. The crystallite size was found to decrease from 57 nm to 37 nm upon increasing the Zr content from 20 to 30 at.% with slight increase in the lattice strain from 0.17 to 0.33%. Further, increase in Zr content to 40 at.% leads to increase in the crystallite size to 57 nm due to stabilization of C10Zr7 phase along with the presence of nanocrystalline Cu-Zr phase. A bimodal distribution of grain size was observed from FE-SEM micrograph was attributed to the highest surface roughness in Zr30Cu70 thin films comprised of Cu10Zr7, Cu9Zr2, Cu-Zr intermetallic phases. In-vitro electrochemical behaviors of nano-crystalline Zrx-Cu100-x thin films in simulated body fluid (SBF) were investigated using potentiodynamic polarization studies. Electrochemical impedance spectroscopy (EIS) data fitting by equivalent electrical circuit fit model suggests that inner bulk layer contributes to high bio-corrosion resistance in Zrx-Cu100-x thin films with increase in Zr content. The results of cyto-compatibility assay suggested that Zr-Cu thin film did not introduce cytotoxicity to osteoblast cells, indicating its suitability as a bio-coating for minimally invasive medical devices.

  8. Pyrolyzed thin film carbon

    Science.gov (United States)

    Tai, Yu-Chong (Inventor); Liger, Matthieu (Inventor); Harder, Theodore (Inventor); Konishi, Satoshi (Inventor); Miserendino, Scott (Inventor)

    2010-01-01

    A method of making carbon thin films comprises depositing a catalyst on a substrate, depositing a hydrocarbon in contact with the catalyst and pyrolyzing the hydrocarbon. A method of controlling a carbon thin film density comprises etching a cavity into a substrate, depositing a hydrocarbon into the cavity, and pyrolyzing the hydrocarbon while in the cavity to form a carbon thin film. Controlling a carbon thin film density is achieved by changing the volume of the cavity. Methods of making carbon containing patterned structures are also provided. Carbon thin films and carbon containing patterned structures can be used in NEMS, MEMS, liquid chromatography, and sensor devices.

  9. Effect of performance of Zr-Y alloy target on thin film deposition technology

    International Nuclear Information System (INIS)

    Pan Qianfu; Liu Chaohong; Jiang Mingzhong; Yin Changgeng

    2011-01-01

    Yttria-stabilized zirconia (YSZ) films are synthesized on corrosion resistant plates by pulsed bias arc ion plating. The arc starting performance and the stability of thin film deposition is explored by improving the uniformity and compactibility of Zr-Y alloy target. The property of Zr-Y alloy target and depositional thin films were measured with the optical microscope, scanning electron microscope, X-ray diffractometer. The result shows that the target with hot rolling and annealing has a good arc starting performance and stability of thin film deposition, and the depositional thin films made of Yttria and amorphous zirconia are homogeneous and compact. (authors)

  10. Resistive Switching Characteristics in Electrochemically Synthesized ZnO Films

    Directory of Open Access Journals (Sweden)

    Shuhan Jing

    2015-04-01

    Full Text Available The semiconductor industry has long been seeking a new kind of non-volatile memory technology with high-density, high-speed, and low-power consumption. This study demonstrated the electrochemical synthesis of ZnO films without adding any soft or hard templates. The effect of deposition temperatures on crystal structure, surface morphology and resistive switching characteristics were investigated. Our findings reveal that the crystallinity, surface morphology and resistive switching characteristics of ZnO thin films can be well tuned by controlling deposition temperature. A conducting filament based model is proposed to explain the switching mechanism in ZnO thin films.

  11. Microstructure and thermochromic properties of VOX-WOX-VOX ceramic thin films

    International Nuclear Information System (INIS)

    Khamseh, S.; Ghahari, M.; Araghi, H.; Faghihi Sani, M.A.

    2016-01-01

    W-doped VO 2 films have been synthesized via oxygen annealing of V-W-V (vanadium-tungsten-vanadium) multilayered films. The effects of middle layer's thickness of V-W-V multilayered film on structure and properties of VO X -WO X -VO X ceramic thin films were investigated. The as-deposited V-W-V multilayered film showed amorphous-like structure when mixed structure of VO 2 (M) and VO 2 (B) was formed in VO X -WO X -VO X ceramic thin films. Tungsten content of VO X -WO X -VO X ceramic thin films increased with increasing middle layer's thickness. With increasing middle layer's thickness, room temperature square resistance (R sq ) of VO X -WO X -VO X ceramic thin films increased from 65 to 86 kΩ/sq. The VO X -WO X -VO X ceramic thin film with the thinnest middle layer showed significant SMT (semiconductor-metal transition) when SMT became negligible on increasing middle layer's thickness. (orig.)

  12. Electroless plating of low-resistivity Cu–Mn alloy thin films with self-forming capacity and enhanced thermal stability

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Sung-Te, E-mail: stchen@mail.hust.edu.tw [Department of Electronic Engineering, Hsiuping University of Science and Technology, Dali 412, Taichung, Taiwan (China); Chen, Giin-Shan [Department of Materials Science and Engineering, Feng Chia University, Seatwen 407, Taichung, Taiwan (China)

    2015-11-05

    Previous studies have typically used sputter deposition to fabricate Cu–Mn alloy thin films with concentrated solute additions which have exceeded several atomic percentages, and the electrical resistivity values of the resultant films from previous studies are relatively high, ranging from 2.5 to 3.5 μΩ-cm. Herein, we proposed a different approach by using electroless process to plate dilute Cu–Mn (0.1 at.%) alloy thin films on dielectric layers (SiO{sub 2}). Upon forming-gas annealing, the Mn incorporated into Cu–Mn films was segregated toward the SiO{sub 2} side, eventually converting itself into a few atomic layer thickness at the Cu/SiO{sub 2} interface, and forming films with a low level of resistivity the same as that of pure Cu films (2.0 μΩ-cm). The interfacial layer served as not only a diffusion barrier, but also an adhesion promoter that prevented the film’s agglomeration during annealing at elevated temperatures. The mechanism for the dual-function performance by the Mn addition was elucidated by interfacial bonding analysis, as well as dynamic (adhesive strength) and thermodynamic (surface-tension) measurements. - Highlights: • Electroless plating is proposed to grow dilute (0.1%) Cu–Mn films on SiO{sub 2} layers. • Adequate annealing results in a self-forming of MnO{sub x} at the Cu/SiO{sub 2} interface. • The role of interfacial MnO{sub x} as a barrier and adhesion promoter is demonstrated. • The treated dilute film has a low ρ level of pure Cu, in contrast to concentrated films. • Its potential as a single entity replacement of Cu interconnect is presented.

  13. thin films

    Indian Academy of Sciences (India)

    microscopy (SEM) studies, respectively. The Fourier transform ... Thin films; chemical synthesis; hydrous tin oxide; FTIR; electrical properties. 1. Introduction ... dehydrogenation of organic compounds (Hattori et al 1987). .... SEM images of (a) bare stainless steel and (b) SnO2:H2O thin film on stainless steel substrate at a ...

  14. Optoelectronic properties of sprayed transparent and conducting indium doped zinc oxide thin films

    International Nuclear Information System (INIS)

    Shinde, S S; Shinde, P S; Bhosale, C H; Rajpure, K Y

    2008-01-01

    Indium doped zinc oxide (IZO) thin films are grown onto Corning glass substrates using the spray pyrolysis technique. The effect of doping concentration on the structural, electrical and optical properties of IZO thin films is studied. X-ray diffraction studies show a change in preferential orientation from the (0 0 2) to the (1 0 1) crystal planes with increase in indium doping concentration. Scanning electron microscopy studies show polycrystalline morphology of the films. Based on the Hall-effect measurements and analysis, impurity scattering is found to be the dominant mechanism determining the diminished mobility in ZnO thin films having higher indium concentration. The addition of indium also induces a drastic decrease in the electrical resistivity of films; the lowest resistivity (4.03 x 10 -5 Ω cm) being observed for the film deposited with 3 at% indium doping. The effect of annealing on the film properties has been reported. Films deposited with 3 at% In concentration have relatively low resistivity with 90% transmittance at 550 nm and the highest value of figure of merit 7.9 x 10 -2 □ Ω -1

  15. Temperature dependence of colossal electro-resistance of Pr0.7Ca0.3MnO3 thin films

    International Nuclear Information System (INIS)

    Odagawa, A.; Kanno, T.; Adachi, H.; Sato, H.; Inoue, I.H.; Akoh, H.; Kawasaki, M.; Tokura, Y.

    2005-01-01

    The electronic conduction through a Pr 0.7 Ca 0.3 MnO 3 thin film is investigated by measurements using dc and pulsed bias. Pr 0.7 Ca 0.3 MnO 3 films sandwiched by electrodes exhibit two stable resistance states by means of applying voltage pulses. Both of the states show semiconducting behavior. The ratio of the two resistance states induces a colossal electro-resistance (CER) effect greater than 1000%. The CER behavior is seen in the temperature range of 300 K down to 150 K. The observed conduction characteristics exhibit the space-charge-limited-current effect, and the switching behavior can be ascribed to a carrier trapping/detrapping of the trap sites in the perovskite manganite

  16. Antibacterial Properties of Titanate Nano fiber Thin Films Formed on a Titanium Plate

    International Nuclear Information System (INIS)

    Yada, M.; Inoue, Y.; Morita, T.; Torikai, T.; Watari, T.; Noda, I.; Hotokebuchi, T.

    2013-01-01

    A sodium titanate nano fiber thin film and a silver nanoparticle/silver titanate nano fiber thin film formed on the surface of a titanium plate exhibited strong antibacterial activities against methicillin-resistant Staphylococcus aureus, which is one of the major bacteria causing in-hospital infections. Exposure of the sodium titanate nano fiber thin film to ultraviolet rays generated a high antibacterial activity due to photo catalysis and the sodium titanate nano fiber thin film immediately after its synthesis possessed a high antibacterial activity even without exposure to ultraviolet rays. Elution of silver from the silver nanoparticle/silver titanate nano fiber thin film caused by the silver ion exchange reaction was considered to contribute substantially to the strong antibacterial activity. The titanate nano fiber thin films adhered firmly to titanium. Therefore, these titanate nano fiber thin film/titanium composites will be extremely useful as implant materials that have excellent antibacterial activities.

  17. Abrasion Wear Resistance, Hardness and Microstructure of Hard Linings Deposited by Means of a Submerged Arc. Dureza, microestructura y resistencia al desgaste por abrasion de recargues duros depositados con arco sumergido

    Energy Technology Data Exchange (ETDEWEB)

    Paranhos, R; Alcoforado, J M; Castillo, J A; Sauer, A

    1989-01-01

    Consumable materials for submerged arc welding of the types alloyed flux-neutral electrode and neutral flux-alloyed electrode were used to form, through multipass welding, a light alloy hard lining of the C-Mn type on ASTM A36 Type structural steel. Emphasis was put on microstructural characterization of the linings surveyed under electron scanning microscopy, and tests were performed to study their hardness and abrasion wear resistance at low pressures. As a result of these tests, a great influence of welding parameters on hardness and abrasion resistance properties of the combination active flux-neutral electrode was noticed. As the results showed no relationship between the hardness and the abrasion wear resistance of the linings surveyed, an attempt was made to relate the resulting microstructure with their abrasion wear resistance. (Author)

  18. Switching, storage, and erasure effects in a superconducting thin film

    International Nuclear Information System (INIS)

    Testardi, L.R.

    1976-01-01

    Thin niobium films can be switched from a superconducting to a resistive state permanently by application of a short electrical pulse. Application of a short pulse of opposite polarity returns the film to the superconducting state

  19. Thickness and microstructure effects in the optical and electrical properties of silver thin films

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Guowen, E-mail: gding@intermolecular.com; Clavero, César; Schweigert, Daniel; Le, Minh [Intermolecular, Inc., 3011 North First Street, San Jose, CA 95134 (United States)

    2015-11-15

    The optical and electrical response of metal thin films approaching thicknesses in the range of the electron mean free path is highly affected by electronic scattering with the interfaces and defects. Here, we present a theoretical and experimental study on how thickness and microstructure affect the properties of Ag thin films. We are able to successfully model the electrical resistivity and IR optical response using a thickness dependent electronic scattering time. Remarkably, the product of electronic scattering time and resistivity remains constant regardless of the thickness (τx ρ = C), with a value of 59 ± 2 μΩ cm ⋅ fs for Ag films in the investigated range from 3 to 74 nm. Our findings enable us to develop a theoretically framework that allows calculating the optical response of metal thin films in the IR by using their measured thickness and resistivity. An excellent agreement is found between experimental measurements and predicted values. This study also shows the theoretical lower limit for emissivity in Ag thin films according to their microstructure and thickness. Application of the model presented here will allow rapid characterization of the IR optical response of metal thin films, with important application in a broad spectrum of fundamental and industrial applications, including optical coatings, low-emissivity windows and semiconductor industry.

  20. Corrosion of thin, magnetron sputtered Nb_2O_5 films

    International Nuclear Information System (INIS)

    Pillis, Marina Fuser; Geribola, Guilherme Altomari; Scheidt, Guilherme; Gonçalves de Araújo, Edval; Lopes de Oliveira, Mara Cristina; Antunes, Renato Altobelli

    2016-01-01

    Highlights: • Niobium oxide based films were obtained by DC magnetron sputtering. • Different deposition times were tested. • The best corrosion resistance was obtained for the Nb_2O_5 film produced at 15′. • Film porosity determines the corrosion resistance. - Abstract: Niobium oxide based thin films were deposited on AISI 316 stainless steel substrates using reactive DC magnetron sputtering. Structure, composition and corrosion resistance of the niobium oxide films were studied. The corrosion behavior of the specimens was evaluated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The concentration of niobium and oxygen in the films was obtained by Rutherford backscattering spectroscopy (RBS). The film structure was analyzed by X-ray diffractometry. The corrosion resistance of the substrate was improved by the Nb_2O_5 layers. The best protective performance was achieved for the deposition time of 15 min.

  1. Thin metal films in resistivity-based chemical sensing

    Czech Academy of Sciences Publication Activity Database

    Podešva, Pavel; Foret, František

    2013-01-01

    Roč. 9, č. 4 (2013), s. 642-652 ISSN 1573-4110 R&D Projects: GA ČR(CZ) GAP301/11/2055 Institutional support: RVO:68081715 Keywords : voltohmmetric sensing * chemiresistor * thin metal film * gas sensing Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.194, year: 2013

  2. Influence of Heat Treatment on Abrasive Wear Resistance of Silumin Matrix Composite Castings

    Directory of Open Access Journals (Sweden)

    Gawdzińska K.

    2016-03-01

    Full Text Available The authors attempted at examining the effect of heat treatment on abrasive wear resistance of metal composite castings. Metal matrix composites were made by infiltrating preforms created from unordered short fibers (graphite or silumin with liquid aluminium alloy AlSi12(b. Thus prepared composites were subject to solution heat treatment at a temperature of 520°C for four hours, then aging at a temperature of 220°C for four hours. Abrasion resistance of the material was tested before and after thermal treatment.

  3. Thermal stability of pulsed laser deposited iridium oxide thin films at low oxygen atmosphere

    Science.gov (United States)

    Gong, Yansheng; Wang, Chuanbin; Shen, Qiang; Zhang, Lianmeng

    2013-11-01

    Iridium oxide (IrO2) thin films have been regarded as a leading candidate for bottom electrode and diffusion barrier of ferroelectric capacitors, some process related issues need to be considered before integrating ferroelectric capacitors into memory cells. This paper presents the thermal stability of pulsed laser deposited IrO2 thin films at low oxygen atmosphere. Emphasis was given on the effect of post-deposition annealing temperature at different oxygen pressure (PO2) on the crystal structure, surface morphology, electrical resistivity, carrier concentration and mobility of IrO2 thin films. The results showed that the thermal stability of IrO2 thin films was strongly dependent on the oxygen pressure and annealing temperature. IrO2 thin films can stably exist below 923 K at PO2 = 1 Pa, which had a higher stability than the previous reported results. The surface morphology of IrO2 thin films depended on PO2 and annealing temperature, showing a flat and uniform surface for the annealed films. Electrical properties were found to be sensitive to both the annealing temperature and oxygen pressure. The room-temperature resistivity of IrO2 thin films with a value of 49-58 μΩ cm increased with annealing temperature at PO2 = 1 Pa. The thermal stability of IrO2 thin films as a function of oxygen pressure and annealing temperature was almost consistent with thermodynamic calculation.

  4. Sputtered molybdenum thin films and the application in CIGS solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, D.; Zhu, H., E-mail: hongbing1982@hotmail.com; Liang, X.; Zhang, C.; Li, Z.; Xu, Y.; Chen, J.; Zhang, L.; Mai, Y., E-mail: yaohuamai@hbu.edu.cn

    2016-01-30

    Graphical abstract: - Highlights: • Mo thin films are prepared by magnetron sputtering. • The dynamic deposition rate increases with the increasing discharge power. • The surface structure of Mo films varies with discharge power and working pressure. • High efficiency CIGS thin film solar cell of 15.2% has been obtained. - Abstract: Molybdenum (Mo) thin films are prepared by magnetron sputtering with different discharge powers and working pressures for the application in Cu(In, Ga)Se{sub 2} (CIGS) thin film solar cells as back electrodes. Properties of these Mo thin films are systematically investigated. It is found that the dynamic deposition rate increases with the increasing discharge power while decreases with the increasing working pressure. The highest dynamic deposition rate of 15.1 nm m/min is achieved for the Mo thin film deposited at the discharge power of 1200 W and at the working pressure of 0.15 Pa. The achieved lowest resistivity of 3.7 × 10{sup −5} Ω cm is attributed to the large grains in the compact thin film. The discharge power and working pressure have great influence on the sputtered Mo thin films. High efficiency of 12.5% was achieved for the Cu(In, Ga)Se{sub 2} (CIGS) thin film solar cells with Mo electrodes prepared at 1200 W and low working pressures. By further optimizing material and device properties, the conversion efficiency has reached to 15.2%.

  5. Thin Film Microbatteries

    International Nuclear Information System (INIS)

    Dudney, Nancy J.

    2008-01-01

    Thin film batteries are built layer by layer by vapor deposition. The resulting battery is formed of parallel plates, much as an ordinary battery construction, just much thinner. The figure (Fig. 1) shows an example of a thin film battery layout where films are deposited symmetrically onto both sides of a supporting substrate. The full stack of films is only 10 to 15 (micro)m thick, but including the support at least doubles the overall battery thickness. When the support is thin, the entire battery can be flexible. At least six companies have commercialized or are very close to commercializing such all-solid-state thin film batteries and market research predicts a growing market and a variety of applications including sensors, RFID tags, and smarter cards. In principle with a large deposition system, a thin film battery might cover a square meter, but in practice, most development is targeting individual cells with active areas less than 25 cm 2 . For very small battery areas, 2 , microfabrication processes have been developed. Typically the assembled batteries have capacities from 0.1 to 5 mAh. The operation of a thin film battery is depicted in the schematic diagram (Fig. 2). Very simply, when the battery is allowed to discharge, a Li + ion migrates from the anode to the cathode film by diffusing through the solid electrolyte. When the anode and cathode reactions are reversible, as for an intercalation compound or alloy, the battery can be recharged by reversing the current. The difference in the electrochemical potential of the lithium determines the cell voltage. Most of the thin films used in current commercial variations of this thin film battery are deposited in vacuum chambers by RF and DC magnetron sputtering and by thermal evaporation onto unheated substrates. In addition, many publications report exploring a variety of other physical and chemical vapor deposition processes, such as pulsed laser deposition, electron cyclotron resonance sputtering, and

  6. Low-temperature technique for thick film resist stabilization and curing

    Science.gov (United States)

    Minter, Jason P.; Wong, Selmer S.; Marlowe, Trey; Ross, Matthew F.; Narcy, Mark E.; Livesay, William R.

    1999-06-01

    For a range of thick film photoresist applications, including MeV ion implant processing, thin film head manufacturing, and microelectromechanical systems processing, there is a need for a low-temperature method for resist stabilization and curing. Traditional methods of stabilizing or curing resist films have relied on thermal cycling, which may not be desirable due to device temperature limitations or thermally-induced distortion of the resist features.

  7. Nanomechanical investigation of thin-film electroceramic/metal-organic framework multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Best, James P., E-mail: james.best@empa.ch, E-mail: engelbert.redel@kit.edu, E-mail: christof.woell@kit.edu; Michler, Johann; Maeder, Xavier [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Mechanics of Materials and Nanostructures, Feuerwerkerstrasse 39, CH-3602 Thun (Switzerland); Liu, Jianxi; Wang, Zhengbang; Tsotsalas, Manuel; Liu, Jinxuan; Gliemann, Hartmut; Weidler, Peter G.; Redel, Engelbert, E-mail: james.best@empa.ch, E-mail: engelbert.redel@kit.edu, E-mail: christof.woell@kit.edu; Wöll, Christof, E-mail: james.best@empa.ch, E-mail: engelbert.redel@kit.edu, E-mail: christof.woell@kit.edu [Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Röse, Silvana [Preparative Macromolecular Chemistry, Institute for Chemical Technology and Polymer Chemistry (ICTP), Karlsruhe Institute of Technology (KIT), Engesserstrasse 18, 76128 Karlsruhe (Germany); Institute for Biological Interfaces (IBG), Karlsruhe Institute of Technology (KIT), Herrmann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Oberst, Vanessa [Institute of Applied Materials (IAM), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Walheim, Stefan [Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2015-09-07

    Thin-film multilayer stacks of mechanically hard magnetron sputtered indium tin oxide (ITO) and mechanically soft highly porous surface anchored metal-organic framework (SURMOF) HKUST-1 were studied using nanoindentation. Crystalline, continuous, and monolithic surface anchored MOF thin films were fabricated using a liquid-phase epitaxial growth method. Control over respective fabrication processes allowed for tuning of the thickness of the thin film systems with a high degree of precision. It was found that the mechanical indentation of such thin films is significantly affected by the substrate properties; however, elastic parameters were able to be decoupled for constituent thin-film materials (E{sub ITO} ≈ 96.7 GPa, E{sub HKUST−1} ≈ 22.0 GPa). For indentation of multilayer stacks, it was found that as the layer thicknesses were increased, while holding the relative thickness of ITO and HKUST-1 constant, the resistance to deformation was significantly altered. Such an observation is likely due to small, albeit significant, changes in film texture, interfacial roughness, size effects, and controlling deformation mechanism as a result of increasing material deposition during processing. Such effects may have consequences regarding the rational mechanical design and utilization of MOF-based hybrid thin-film devices.

  8. Nanomechanical investigation of thin-film electroceramic/metal-organic framework multilayers

    International Nuclear Information System (INIS)

    Best, James P.; Michler, Johann; Maeder, Xavier; Liu, Jianxi; Wang, Zhengbang; Tsotsalas, Manuel; Liu, Jinxuan; Gliemann, Hartmut; Weidler, Peter G.; Redel, Engelbert; Wöll, Christof; Röse, Silvana; Oberst, Vanessa; Walheim, Stefan

    2015-01-01

    Thin-film multilayer stacks of mechanically hard magnetron sputtered indium tin oxide (ITO) and mechanically soft highly porous surface anchored metal-organic framework (SURMOF) HKUST-1 were studied using nanoindentation. Crystalline, continuous, and monolithic surface anchored MOF thin films were fabricated using a liquid-phase epitaxial growth method. Control over respective fabrication processes allowed for tuning of the thickness of the thin film systems with a high degree of precision. It was found that the mechanical indentation of such thin films is significantly affected by the substrate properties; however, elastic parameters were able to be decoupled for constituent thin-film materials (E ITO  ≈ 96.7 GPa, E HKUST−1  ≈ 22.0 GPa). For indentation of multilayer stacks, it was found that as the layer thicknesses were increased, while holding the relative thickness of ITO and HKUST-1 constant, the resistance to deformation was significantly altered. Such an observation is likely due to small, albeit significant, changes in film texture, interfacial roughness, size effects, and controlling deformation mechanism as a result of increasing material deposition during processing. Such effects may have consequences regarding the rational mechanical design and utilization of MOF-based hybrid thin-film devices

  9. Rapid amplification/detection of nucleic acid targets utilizing a HDA/thin film biosensor.

    Science.gov (United States)

    Jenison, Robert; Jaeckel, Heidi; Klonoski, Joshua; Latorra, David; Wiens, Jacinta

    2014-08-07

    Thin film biosensors exploit a flat, optically coated silicon-based surface whereupon formation of nucleic acid hybrids are enzymatically transduced in a molecular thin film that can be detected by the unaided human eye under white light. While the limit of sensitivity for detection of nucleic acid targets is at sub-attomole levels (60 000 copies) many clinical specimens containing bacterial pathogens have much lower levels of analyte present. Herein, we describe a platform, termed HDA/thin film biosensor, which performs helicase-dependant nucleic acid amplification on a thin film biosensor surface to improve the limit of sensitivity to 10 copies of the mecA gene present in methicillin-resistant strains of Staphylococcus. As double-stranded DNA is unwound by helicase it was either bound by solution-phase DNA primers to be copied by DNA polymerase or hybridized to surface immobilized probe on the thin film biosensor surface to be detected. Herein, we show that amplification reactions on the thin film biosensor are equivalent to in standard thin wall tubes, with detection at the limit of sensitivity of the assay occurring after 30 minutes of incubation time. Further we validate the approach by detecting the presence of the mecA gene in methicillin-resistant Staphylococcus aureus (MRSA) from positive blood culture aliquots with high specificity (signal/noise ratio of 105).

  10. A new lithography of functional plasma polymerized thin films

    International Nuclear Information System (INIS)

    Kim, Sung-O

    2001-01-01

    The preparation of the resist for the vacuum lithography was carried out by plasma polymerization. The resist manufactured by plasma polymerization is a monomer produced by MMA (Methyl methacrylate). The functional groups of MMA appeared in the PPMMA (Plasma Polymerized Methyl methacrylate) as well, and this was confirmed through an analysis using FT-IR. The polymerization rate increased as a function of the plasma power and decreased as a function of the system pressure. The sensitivity and contrast of the plasma polymerized thin films were 15 μC/cm2 and 4.3 respectively. The size of the pattern manufactured by Vacuum Lithography using the plasma polymerized thin films was 100 nm

  11. Determination of magnetic properties of multilayer metallic thin films

    International Nuclear Information System (INIS)

    Birlikseven, C.

    2000-01-01

    In recent year, Giant Magnetoresistance Effect has been attracting an increasingly high interest. High sensitivity magnetic field detectors and high sensitivity read heads of magnetic media can be named as important applications of these films. In this work, magnetic and electrical properties of single layer and thin films were investigated. Multilayer thin films were supplied by Prof. Dr. A. Riza Koeymen from Texas University. Multilayer magnetic thin films are used especially for magnetic reading and magnetic writing. storing of large amount of information into small areas become possible with this technology. Single layer films were prepared using the electron beam evaporation technique. For the exact determination of film thicknesses, a careful calibration of the thicknesses was made. Magnetic properties of the multilayer films were studied using the magnetization, magnetoresistance measurements and ferromagnetic resonance technique. Besides, by fitting the experimental results to the theoretical models, effective magnetization and angles between the ferromagnetic layers were calculated. The correspondence between magnetization and magnetoresistance was evaluated. To see the effect of anisotropic magnetoresistance in the magnetoresistance measurements, a new experimental set-up was build and measurements were taken in this set-up. A series of soft permalloy thin films were made, and temperature dependent resistivity, magnetoresistance, anisotropic magnetoresistance and magnetization measurements were taken

  12. Influence of Magnetic Field on Electric Charge Transport in Holomiun Thin Films at Low Temperatures

    Directory of Open Access Journals (Sweden)

    Jan Dudas

    2005-01-01

    Full Text Available Holmium thin films were prepared by evaporation in ultrahigh vacuum (UHV and high precision electrical resistance measurements were performed on them as well as on holomium bulk sample in the wide temperature range from 4,2 K up to the room temperature. Electric charge transport is profoundly influenced by the magnetic structure at low temperatures and a "knee-like" resistance anomaly was observed near the transportation from paramagnetic state to basal-plane spiral structure in bulk with the Neel temperature TN=128,9 K and below ~ 122 K in thin Ho films in a thickness range from 98 nm to 215 nm. Unexpected resistance minimum at ~ 9 K and a slope´s charge of the R vs. T curve near ~ 170 K was observed in 215 nm thin film. Application of magnetic field parallel to the substrate and thin film plane for temperatures below ~ 150 K caused the decrease of resistence value with increasing magnetic flux density. Increasing suppression of the TN value up to ~ 5 K with increasing flux density value up to 5 T was observed in Ho films

  13. Hall effect measurement for precise sheet resistance and thickness evaluation of Ruthenium thin films using non-equidistant four-point probes

    Directory of Open Access Journals (Sweden)

    Frederik Westergaard Østerberg

    2018-05-01

    Full Text Available We present a new micro Hall effect measurement method using non-equidistant electrodes. We show theoretically and verify experimentally that it is advantageous to use non-equidistant electrodes for samples with low Hall sheet resistance. We demonstrate the new method by experiments where Hall sheet carrier densities and Hall mobilities of Ruthenium thin films (3-30 nm are determined. The measurements show that it is possible to measure Hall mobilities as low as 1 cm2V−1s−1 with a relative standard deviation of 2-3%. We show a linear relation between measured Hall sheet carrier density and film thickness. Thus, the method can be used to monitor thickness variations of ultra-thin metal films.

  14. Combustion synthesized indium-tin-oxide (ITO) thin film for source/drain electrodes in all solution-processed oxide thin-film transistors

    International Nuclear Information System (INIS)

    Tue, Phan Trong; Inoue, Satoshi; Takamura, Yuzuru; Shimoda, Tatsuya

    2016-01-01

    We report combustion solution synthesized (SCS) indium-tin-oxide (ITO) thin film, which is a well-known transparent conductive oxide, for source/drain (S/D) electrodes in solution-processed amorphous zirconium-indium-zinc-oxide TFT. A redox-based combustion synthetic approach is applied to ITO thin film using acetylacetone as a fuel and metal nitrate as oxidizer. The structural and electrical properties of SCS-ITO precursor solution and thin films were systematically investigated with changes in tin concentration, indium metal precursors, and annealing conditions such as temperature, time, and ambient. It was found that at optimal conditions the SCS-ITO thin film exhibited high crystalline quality, atomically smooth surface (RMS ∝ 4.1 Aa), and low electrical resistivity (4.2 x 10 -4 Ω cm). The TFT using SCS-ITO film as the S/D electrodes showed excellent electrical properties with negligible hysteresis. The obtained ''on/off'' current ratio, subthreshold swing factor, subthreshold voltage, and field-effect mobility were 5 x 10 7 , 0.43 V/decade, 0.7 V, and 2.1 cm 2 /V s, respectively. The performance and stability of the SCS-ITO TFT are comparable to those of the sputtered-ITO TFT, emphasizing that the SCS-ITO film is a promising candidate for totally solution-processed oxide TFTs. (orig.)

  15. The Characterization of Thin Film Nickel Titanium Shape Memory Alloys

    Science.gov (United States)

    Harris Odum, Nicole Latrice

    Shape memory alloys (SMA) are able to recover their original shape through the appropriate heat or stress exposure after enduring mechanical deformation at a low temperature. Numerous alloy systems have been discovered which produce this unique feature like TiNb, AgCd, NiAl, NiTi, and CuZnAl. Since their discovery, bulk scale SMAs have undergone extensive material property investigations and are employed in real world applications. However, its thin film counterparts have been modestly investigated and applied. Researchers have introduced numerous theoretical microelectromechanical system (MEMS) devices; yet, the research community's overall unfamiliarity with the thin film properties has delayed growth in this area. In addition, it has been difficult to outline efficient thin film processing techniques. In this dissertation, NiTi thin film processing and characterization techniques will be outlined and discussed. NiTi thin films---1 mum thick---were produced using sputter deposition techniques. Substrate bound thin films were deposited to analysis the surface using Scanning Electron Microscopy; the film composition was obtained using Energy Dispersive Spectroscopy; the phases were identified using X-ray diffraction; and the transformation temperatures acquired using resistivity testing. Microfabrication processing and sputter deposition were employed to develop tensile membranes for membrane deflection experimentation to gain insight on the mechanical properties of the thin films. The incorporation of these findings will aid in the movement of SMA microactuation devices from theory to fruition and greatly benefit industries such as medicinal and aeronautical.

  16. Ceramic Composite Thin Films

    Science.gov (United States)

    Ruoff, Rodney S. (Inventor); Stankovich, Sasha (Inventor); Dikin, Dmitriy A. (Inventor); Nguyen, SonBinh T. (Inventor)

    2013-01-01

    A ceramic composite thin film or layer includes individual graphene oxide and/or electrically conductive graphene sheets dispersed in a ceramic (e.g. silica) matrix. The thin film or layer can be electrically conductive film or layer depending the amount of graphene sheets present. The composite films or layers are transparent, chemically inert and compatible with both glass and hydrophilic SiOx/silicon substrates. The composite film or layer can be produced by making a suspension of graphene oxide sheet fragments, introducing a silica-precursor or silica to the suspension to form a sol, depositing the sol on a substrate as thin film or layer, at least partially reducing the graphene oxide sheets to conductive graphene sheets, and thermally consolidating the thin film or layer to form a silica matrix in which the graphene oxide and/or graphene sheets are dispersed.

  17. Raman scattering, electrical and optical properties of fluorine-doped tin oxide thin films with (200) and (301) preferred orientation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang-Yeoul, E-mail: cykim15@kicet.re.kr [Nano-Convergence Intelligence Material Team, Korea Institute of Ceramic Eng. and Tech., Gasan-digtial-ro 10 Gil 77 Geumcheon-gu, 153-801 Seoul (Korea, Republic of); Riu, Doh-Hyung [Dept. of New Material Sci. and Eng., Seoul National University of Technology, Seoul (Korea, Republic of)

    2014-12-15

    (200) and (301) preferred oriented fluorine-doped tin oxide (FTO) thin films were fabricated by spray pyrolysis of ethanol-added and water-based FTO precursor solutions, respectively. (200) oriented FTO thin film from ethanol-added solution shows the lower electrical resistivity and visible light transmission than (301) preferred thin film from water-based solution. It is due to the higher carrier concentration and electron mobility in (200) oriented crystals, that is, the lower ionized impurity scattering. The higher electron concentration is related to the higher optical band gap energy, the lower visible light transmission, and the higher IR reflection. For (301) preferred FTO thin films from water-based solution, the lower carrier concentration and electron mobility make the higher electrical resistivity and visible light transmission. Raman scattering analysis shows that IR active modes prominent in (200) oriented FTO thin film are related with the lower electrical resistivity. - Highlights: • We coated fluorine-doped tin oxide thin films with preferred orientation of (200) and (301). • We examine changes in the level of electrical and optical properties with the orientation. • (200) preferred orientation showed lower electrical resistivity and optical transmittance. • (200) oriented thin films have higher electron concentrations that are related with IR active modes.

  18. Processing of thin SU-8 films

    International Nuclear Information System (INIS)

    Keller, Stephan; Blagoi, Gabriela; Lillemose, Michael; Haefliger, Daniel; Boisen, Anja

    2008-01-01

    This paper summarizes the results of the process optimization for SU-8 films with thicknesses ≤5 µm. The influence of soft-bake conditions, exposure dose and post-exposure-bake parameters on residual film stress, structural stability and lithographic resolution was investigated. Conventionally, the SU-8 is soft-baked after spin coating to remove the solvent. After the exposure, a post-exposure bake at a high temperature T PEB ≥ 90 °C is required to cross-link the resist. However, for thin SU-8 films this often results in cracking or delamination due to residual film stress. The approach of the process optimization is to keep a considerable amount of the solvent in the SU-8 before exposure to facilitate photo-acid diffusion and to increase the mobility of the monomers. The experiments demonstrate that a replacement of the soft-bake by a short solvent evaporation time at ambient temperature allows cross-linking of the thin SU-8 films even at a low T PEB = 50 °C. Fourier-transform infrared spectroscopy is used to confirm the increased cross-linking density. The low thermal stress due to the reduced T PEB and the improved structural stability result in crack-free structures and solve the issue of delamination. The knowledge of the influence of different processing parameters on the responses allows the design of optimized processes for thin SU-8 films depending on the specific application

  19. Abrasion Properties of Steel Fiber Reinforced Silica Fume Concrete According to Los Angeles and Water Abrasion Tests

    Directory of Open Access Journals (Sweden)

    Tsan-Ching CHENG

    2014-12-01

    Full Text Available The current study mainly investigated the influence of different tests on the abrasion resistance of concrete mixed with steel fibers and silica fume. The abrasion resistance was assessed at 28, 56 and 91 days on concretes with water-binder ratios of 0.35 and 0.55 where in some mixes silica fume was substituted by 5 % of cement by weight. Steel fibers of 0.5 % and 1.0 % of concrete volume were also added into the test concrete by replacement of coarse and fine aggregates. The results showed that concrete with higher compressive strength in Los Angeles abrasion tests also had better abrasion resistance. The inclusion of steel fibers into test concrete with a water-binder ratio of 0.35 resulted in a significant increase in compressive strength. This concrete also displayed better abrasion resistance and splitting tensile strength than reference concrete; in the test sample with a water-binder ratio of 0.55, the added steel fibers was unable to effectively produce cementation with the concrete. The inclusion of silica fume improved the abrasion resistance of concretes. In water abrasion testing, the abrasion resistance of concrete containing steel fiber was worse than that of concrete without steel fibers. In the water abrasion testing, the surface of steel fiber reinforced concrete was eroded by water and steel balls, and the impact caused the steel fibers to separate from the concrete and led to higher wear loss. DOI: http://dx.doi.org/10.5755/j01.ms.20.4.6460

  20. Thickness and microstructure effects in the optical and electrical properties of silver thin films

    Directory of Open Access Journals (Sweden)

    Guowen Ding

    2015-11-01

    Full Text Available The optical and electrical response of metal thin films approaching thicknesses in the range of the electron mean free path is highly affected by electronic scattering with the interfaces and defects. Here, we present a theoretical and experimental study on how thickness and microstructure affect the properties of Ag thin films. We are able to successfully model the electrical resistivity and IR optical response using a thickness dependent electronic scattering time. Remarkably, the product of electronic scattering time and resistivity remains constant regardless of the thickness (τx ρ = C, with a value of 59 ± 2 μΩ cm ⋅ fs for Ag films in the investigated range from 3 to 74 nm. Our findings enable us to develop a theoretically framework that allows calculating the optical response of metal thin films in the IR by using their measured thickness and resistivity. An excellent agreement is found between experimental measurements and predicted values. This study also shows the theoretical lower limit for emissivity in Ag thin films according to their microstructure and thickness. Application of the model presented here will allow rapid characterization of the IR optical response of metal thin films, with important application in a broad spectrum of fundamental and industrial applications, including optical coatings, low-emissivity windows and semiconductor industry.

  1. Transient behaviors of ZnO thin films on a transparent, flexible polyethylene terephthalate substrate

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Jun [Department of Nano-Physics, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si, Gyeonggi-do 461-701 (Korea, Republic of); Lee, Ho Seok [Department of Materials Science and Engineering, Korea University, 5-1 Anam-dong, Seongbuk-gu, Seoul 136-713 (Korea, Republic of); Noh, Jin-Seo, E-mail: jinseonoh@gachon.ac.kr [Department of Nano-Physics, Gachon University, 1342 Seongnamdaero, Sujeong-gu, Seongnam-si, Gyeonggi-do 461-701 (Korea, Republic of)

    2016-03-31

    Thickness-dependent electrical, structural, and optical properties of zinc oxide (ZnO) thin films on polyethylene terephthalate (PET) substrates have been investigated in the very thin thickness range of 20 to 120 nm. In this thickness range, the electrical resistance of ZnO film increased with an increase in film thickness. This unusual transition behavior was explained in terms of structural evolution from Zn-phase-incorporating non-crystalline ZnO to hexagonal-structured ZnO. A critical thickness for the full development of hexagonal ZnO crystal was estimated at approximately 80 nm in this study. ZnO thin films on PET substrates exhibit a high optical transmittance of > 70% and good endurance to bending cycles over the measured thickness range. The results of this study indicate that a trade-off should be sought between structural, electrical, optical, and mechanical properties for practical applications of very thin ZnO films on organic substrates. - Highlights: • Very thin ZnO films were sputter-deposited on the PET substrate. • The ZnO film resistance increases with an increase in film thickness until saturation. • Hexagonal crystal structures gradually develop with increasing film thickness. • A Zn phase appears in a 20-nm-thick ZnO film. • ZnO films show high optical transmittance of > 80% and good endurance to bending.

  2. Transient behaviors of ZnO thin films on a transparent, flexible polyethylene terephthalate substrate

    International Nuclear Information System (INIS)

    Kim, Yong Jun; Lee, Ho Seok; Noh, Jin-Seo

    2016-01-01

    Thickness-dependent electrical, structural, and optical properties of zinc oxide (ZnO) thin films on polyethylene terephthalate (PET) substrates have been investigated in the very thin thickness range of 20 to 120 nm. In this thickness range, the electrical resistance of ZnO film increased with an increase in film thickness. This unusual transition behavior was explained in terms of structural evolution from Zn-phase-incorporating non-crystalline ZnO to hexagonal-structured ZnO. A critical thickness for the full development of hexagonal ZnO crystal was estimated at approximately 80 nm in this study. ZnO thin films on PET substrates exhibit a high optical transmittance of > 70% and good endurance to bending cycles over the measured thickness range. The results of this study indicate that a trade-off should be sought between structural, electrical, optical, and mechanical properties for practical applications of very thin ZnO films on organic substrates. - Highlights: • Very thin ZnO films were sputter-deposited on the PET substrate. • The ZnO film resistance increases with an increase in film thickness until saturation. • Hexagonal crystal structures gradually develop with increasing film thickness. • A Zn phase appears in a 20-nm-thick ZnO film. • ZnO films show high optical transmittance of > 80% and good endurance to bending.

  3. Uniaxial anisotropy in magnetite thin film-Magnetization studies

    International Nuclear Information System (INIS)

    Wiechec, A.; Korecki, J.; Handke, B.; Kakol, Z.; Owoc, D.; Antolak, D.A.; Kozlowski, A.

    2006-01-01

    Magnetization and electrical resistivity measurements have been performed on a stoichiometric single crystalline magnetite Fe 3 O 4 thin film (thickness of ca. 500 nm) MBE deposited on MgO (1 0 0) substrate. The aim of these studies was to check the influence of preparation method and sample form (bulk vs. thin film) on magnetic anisotropy properties in magnetite. The film magnetization along versus applied magnetic field has been determined both in the direction parallel and perpendicular to the film surface, and at temperatures above and below the Verwey transition. We have found, in agreement with published results, that the in-plane field of 10 kOe was not sufficient to saturate the sample. This can be understood if some additional factor, on top of the bulk magnetocrystalline anisotropy, is taken into account

  4. Transport physics and device modeling of zinc oxide thin-film transistors. Pt. II: Contact Resistance in Short Channel Devices

    NARCIS (Netherlands)

    Torricelli, F.; Meijboom, J.R.; Smits, E.; Tripathi, A.K.; Gelinck, G.H.; Colalongo, L.; Kovacs-Vajna, Z.M.; Leeuw, D. de; Cantatore, E.

    2011-01-01

    Abstract—Short-channel zinc oxide (ZnO) thin-film transistors (TFTs) are investigated in a wide range of temperatures and bias conditions. Scaling down the channel length, the TFT performance is seriously affected by contact resistances, which depend on gate voltage and temperature. To account for

  5. Transport physics and device modeling of zinc oxide thin film transistors - part II : contact resistance in short channel devices

    NARCIS (Netherlands)

    Torricelli, F.; Smits, E.C.P.; Meijboom, J.R.; Tripathi, A.K.; Gelinck, G.H.; Colalongo, L.; Kovacs-Vajna, Z.M.; Cantatore, E.

    2011-01-01

    Short-channel zinc oxide (ZnO) thin-film transistors (TFTs) are investigated in a wide range of temperatures and bias conditions. Scaling down the channel length, the TFT performance is seriously affected by contact resistances, which depend on gate voltage and temperature. To account for the

  6. Vanadium oxide thin films deposited on silicon dioxide buffer layers by magnetron sputtering

    International Nuclear Information System (INIS)

    Chen Sihai; Ma Hong; Wang Shuangbao; Shen Nan; Xiao Jing; Zhou Hao; Zhao Xiaomei; Li Yi; Yi Xinjian

    2006-01-01

    Thin films made by vanadium oxide have been obtained by direct current magnetron sputtering method on SiO 2 buffer layers. A detailed electrical and structural characterization has been performed on the deposited films by four-point probe method and scanning electron microscopy (SEM). At room temperature, the four-point probe measurement result presents the resistance of the film to be 25 kU/sheet. The temperature coefficient of resistance is - 2.0%/K. SEM image indicates that the vanadium oxide exhibits a submicrostructure with lamella size ranging from 60 nm to 300 nm. A 32 x 32-element test microbolometer was fabricated based on the deposited thin film. The infrared response testing showed that the response was 200 mV. The obtained results allow us to conclude that the vanadium oxide thin films on SiO 2 buffer layers is suitable for uncooled focal plane arrays applications

  7. Investigation of the magnetic properties of electrodeposited NiFe thin films

    International Nuclear Information System (INIS)

    Bakkaloglu, O. F.; Bedir, M.; Oeztas, M.; Karahan, I. H.

    2002-01-01

    Most magnetic devices used today are based on the magnetic thin film. Rapid and extensive developments in magnetic sensor / actuator and magnetic recording technology place a growing demand on the use of different thin film fabrication techniques for magnetic materials. The electroplating technique is especially interesting due to its low cost, high throughput and high quality of the deposits which are extensively used in the magnetic recording industry to deposit relatively thick permalloy layers. Much recent attention has focused on the electrodeposited NiFe thin films, which exhibit giant magneto resistive behaviour as well as anisotropic magnetoresistance properties. n this study, NiFe thin films were developed by using electrodeposition technique and their crystallinity structures were investigated by using x-ray diffractometer measurements. The magneto resistive properties of the samples were investigated by Wan der Pauw method with a home made electromagnet under the different magnetic fields. The magnetoresistance measurements of the samples were carried out in two configurations; current parallel ( longitudinal ) and perpendicular ( transverse ) to the magnetic field. In the longitudinal configuration giant magnetoresistance was observed while anisotropic magnetoresistance was detected in the other configuration

  8. Nanocrystalline magnetite thin films grown by dual ion-beam sputtering

    International Nuclear Information System (INIS)

    Prieto, Pilar; Ruiz, Patricia; Ferrer, Isabel J.; Figuera, Juan de la; Marco, José F.

    2015-01-01

    Highlights: • We have grown tensile and compressive strained nanocrystalline magnetite thin films by dual ion beam sputtering. • The magnetic and thermoelectric properties can be controlled by the deposition conditions. • The magnetic anisotropy depends on the crystalline grain size. • The thermoelectric properties depend on the type of strain induced in the films. • In plane uniaxial magnetic anisotropy develops in magnetite thin films with grain sizes ⩽20 nm. - Abstract: We have explored the influence of an ion-assisted beam in the thermoelectric and magnetic properties of nanocrystalline magnetite thin films grown by ion-beam sputtering. The microstructure has been investigated by XRD. Tensile and compressive strained thin films have been obtained as a function of the parameters of the ion-assisted beam. The evolution of the in-plane magnetic anisotropy was attributed to crystalline grain size. In some films, magneto-optical Kerr effect measurements reveal the existence of uniaxial magnetic anisotropy induced by the deposition process related with a small grain size (⩽20 nm). Isotropic magnetic properties have observed in nanocrystalline magnetite thin film having larger grain sizes. The largest power factor of all the films prepared (0.47 μW/K 2 cm), obtained from a Seebeck coefficient of −80 μV/K and an electrical resistivity of 13 mΩ cm, is obtained in a nanocrystalline magnetite thin film with an expanded out-of-plane lattice and with a grain size ≈30 nm

  9. Room temperature resistive state switching with hysteresis in GdMnO3 thin film with low threshold voltage

    International Nuclear Information System (INIS)

    Nath, Rajib; Raychaudhuri, A. K.; Mukovskii, Ya. M.; Andreev, N.; Chichkov, Vladimir

    2014-01-01

    In this paper, we report a room temperature resistive state switching with hysteresis, in a thin film of GdMnO 3 grown on NdGaO 3 substrate. The switched states have a resistance ratio ≈10 3 . The switching is unipolar in nature, with a low set voltage <3 V, while the reset voltage <0.3 V. The switching occurs between a high resistance polaronic insulating state and a low resistance metallic state. The resistance state transition has been ascribed to an electronic mechanism that originates from co-existing phases (created by charge disproportionation) that can undergo a percolative transition enabled by the applied bias

  10. Structural and morphological properties of ITO thin films grown by magnetron sputtering

    Science.gov (United States)

    Ghorannevis, Z.; Akbarnejad, E.; Ghoranneviss, M.

    2015-10-01

    Physical properties of transparent and conducting indium tin oxide (ITO) thin films grown by radiofrequency (RF) magnetron sputtering are studied systematically by changing deposition time. The X-ray diffraction (XRD) data indicate polycrystalline thin films with grain orientations predominantly along the (2 2 2) and (4 0 0) directions. From atomic force microscopy (AFM) it is found that by increasing the deposition time, the roughness of the film increases. Scanning electron microscopy (SEM) images show a network of a high-porosity interconnected nanoparticles, which approximately have a pore size ranging between 20 and 30 nm. Optical measurements suggest an average transmission of 80 % for the ITO films. Sheet resistances are investigated using four-point probes, which imply that by increasing the film thickness the resistivities of the films decrease to 2.43 × 10-5 Ω cm.

  11. Electrical properties of resistive switches based on Ba1-χSrχTiO3 thin films prepared by RF co-sputtering

    International Nuclear Information System (INIS)

    Marquez H, A.; Hernandez R, E.; Zapata T, M.; Guillen R, J.; Cruz, M. P.; Calzadilla A, O.; Melendez L, M.

    2010-01-01

    In this work, was proposed the use of Ba 1-χ Sr χ TiO 3 (0≤x≤1) thin films for the construction of metal-insulator-metal heterostructures; and their great potential for the development of non-volatile resistance memories (ReRAM) is shown. The deposition of Ba 1-χ Sr χ TiO 3 thin films was done by the RF co-sputtering technique using two magnetron sputtering cathodes with BaTiO 3 and SrTiO 3 targets. The chemical composition (x parameter) in the deposited Ba 1-χ Sr χ TiO 3 thin films was varied through the RF powder applied to the targets. The constructed metal-insulator-metal heterostructures were Al/Ba 1-χ Sr χ TiO 3 /nichrome. The I-V measurements of the heterostructures showed that their hysteretic characteristics change depending on the Ba/Sr ratio of the Ba 1-χ Sr χ TiO 3 thin films; the Ba/Sr ratio was determined by employing the energy dispersive spectroscopy; Sem micrographs showed that Ba 1-χ Sr χ TiO 3 thin films were uniform without cracks or pinholes. Additionally, the analysis of the X-ray diffraction results indicated the substitutional incorporation of Sr into the BaTiO 3 lattice and the obtainment of crystalline films for the entire range of the x values. (Author)

  12. Orientation control of chemical solution deposited LaNiO3 thin films

    International Nuclear Information System (INIS)

    Ueno, Kengo; Yamaguchi, Toshiaki; Sakamoto, Wataru; Yogo, Toshinobu; Kikuta, Koichi; Hirano, Shin-ichi

    2005-01-01

    High quality LaNiO 3 (LNO) thin films with preferred orientation could be synthesized on Pt/Ti/SiO 2 /Si substrates at 700 deg. C using the chemical solution deposition method. The homogeneous and stable LNO precursor solutions were prepared using lanthanum isopropoxide and nickel (II) acetylacetonate in a mixed solvent of absolute ethanol and 2-methoxyethanol. The oriented LNO thin films exhibit metallic electro-conduction, and their resistivity at room temperature is sufficiently low for making them an alternative electrode material for functional ceramic thin films

  13. Laser deposition of SmCo thin film and coating on different substrates

    International Nuclear Information System (INIS)

    Allocca, L; Bonavolonta, C; Valentino, M; Giardini, A; Lopizzo, T; Morone, A; Verrastro, M F; Viggiano, V

    2008-01-01

    Thin films and coatings of permanent magnetic materials are very important for different electronic and micromechanical applications. This paper deals with the fabrication, using pulsed laser deposition (PLD) technique, of good quality magnetic SmCo thin films on polycarbonate, steel, silicon and amorphous quartz substrates, for low cost electronic applications like radio frequency identification (RFID) antennas and electromechanical devices for fuel feeding control in the automotive. X-ray fluorescence and magnetic scanning measurements using giant magneto-resistive (GMR) sensors have been performed to study the functional magnetic properties of the deposited thin films.

  14. Host thin films incorporating nanoparticles

    Science.gov (United States)

    Qureshi, Uzma

    The focus of this research project was the investigation of the functional properties of thin films that incorporate a secondary nanoparticulate phase. In particular to assess if the secondary nanoparticulate material enhanced a functional property of the coating on glass. In order to achieve this, new thin film deposition methods were developed, namely use of nanopowder precursors, an aerosol assisted transport technique and an aerosol into atmospheric pressure chemical vapour deposition system. Aerosol assisted chemical vapour deposition (AACVD) was used to deposit 8 series of thin films on glass. Five different nanoparticles silver, gold, ceria, tungsten oxide and zinc oxide were tested and shown to successfully deposit thin films incorporating nanoparticles within a host matrix. Silver nanoparticles were synthesised and doped within a titania film by AACVD. This improved solar control properties. A unique aerosol assisted chemical vapour deposition (AACVD) into atmospheric pressure chemical vapour deposition (APCVD) system was used to deposit films of Au nanoparticles and thin films of gold nanoparticles incorporated within a host titania matrix. Incorporation of high refractive index contrast metal oxide particles within a host film altered the film colour. The key goal was to test the potential of nanopowder forms and transfer the suspended nanopowder via an aerosol to a substrate in order to deposit a thin film. Discrete tungsten oxide nanoparticles or ceria nanoparticles within a titanium dioxide thin film enhanced the self-cleaning and photo-induced super-hydrophilicity. The nanopowder precursor study was extended by deposition of zinc oxide thin films incorporating Au nanoparticles and also ZnO films deposited from a ZnO nanopowder precursor. Incorporation of Au nanoparticles within a VO: host matrix improved the thermochromic response, optical and colour properties. Composite VC/TiC and Au nanoparticle/V02/Ti02 thin films displayed three useful

  15. Abrasive Wear Resistance of Tool Steels Evaluated by the Pin-on-Disc Testing

    Science.gov (United States)

    Bressan, José Divo; Schopf, Roberto Alexandre

    2011-05-01

    Present work examines tool steels abrasion wear resistance and the abrasion mechanisms which are one main contributor to failure of tooling in metal forming industry. Tooling used in cutting and metal forming processes without lubrication fails due to this type of wear. In the workshop and engineering practice, it is common to relate wear resistance as function of material hardness only. However, there are others parameters which influences wear such as: fracture toughness, type of crystalline structure and the occurrence of hard precipitate in the metallic matrix and also its nature. In the present investigation, the wear mechanisms acting in tool steels were analyzed and, by normalized tests, wear resistance performance of nine different types of tool steels were evaluated by pin-on-disc testing. Conventional tool steels commonly used in tooling such as AISI H13 and AISI A2 were compared in relation to tool steels fabricated by sintering process such as Crucible CPM 3V, CPM 9V and M4 steels. Friction and wear testing were carried out in a pin-on-disc automated equipment which pin was tool steel and the counter-face was a abrasive disc of silicon carbide. Normal load of 5 N, sliding velocity of 0.45 m/s, total sliding distance of 3000 m and room temperature were employed. The wear rate was calculated by the Archard's equation and from the plotted graphs of pin cumulated volume loss versus sliding distance. Specimens were appropriately heat treated by quenching and three tempering cycles. Percentage of alloying elements, metallographic analyses of microstructure and Vickers microhardness of specimens were performed, analyzed and correlated with wear rate. The work is concluded by the presentation of a rank of tool steel wear rate, comparing the different tool steel abrasion wear resistance: the best tool steel wear resistance evaluated was the Crucible CPM 9V steel.

  16. Thin film silicon photovoltaics: Architectural perspectives and technological issues

    Energy Technology Data Exchange (ETDEWEB)

    Mercaldo, Lucia Vittoria; Addonizio, Maria Luisa; Noce, Marco Della; Veneri, Paola Delli; Scognamiglio, Alessandra; Privato, Carlo [ENEA, Portici Research Center, Piazzale E. Fermi, 80055 Portici (Napoli) (Italy)

    2009-10-15

    Thin film photovoltaics is a particularly attractive technology for building integration. In this paper, we present our analysis on architectural issues and technological developments of thin film silicon photovoltaics. In particular, we focus on our activities related to transparent and conductive oxide (TCO) and thin film amorphous and microcrystalline silicon solar cells. The research on TCO films is mainly dedicated to large-area deposition of zinc oxide (ZnO) by low pressure-metallorganic chemical vapor deposition. ZnO material, with a low sheet resistance (<8 {omega}/sq) and with an excellent transmittance (>82%) in the whole wavelength range of photovoltaic interest, has been obtained. ''Micromorph'' tandem devices, consisting of an amorphous silicon top cell and a microcrystalline silicon bottom cell, are fabricated by using the very high frequency plasma enhanced chemical vapor deposition technique. An initial efficiency of 11.1% (>10% stabilized) has been obtained. (author)

  17. Pulsed laser deposited Al-doped ZnO thin films for optical applications

    Directory of Open Access Journals (Sweden)

    Gurpreet Kaur

    2015-02-01

    Full Text Available Highly transparent and conducting Al-doped ZnO (Al:ZnO thin films were grown on glass substrates using pulsed laser deposition technique. The profound effect of film thickness on the structural, optical and electrical properties of Al:ZnO thin films was observed. The X-ray diffraction depicts c-axis, plane (002 oriented thin films with hexagonal wurtzite crystal structure. Al-doping in ZnO introduces a compressive stress in the films which increase with the film thickness. AFM images reveal the columnar grain formation with low surface roughness. The versatile optical properties of Al:ZnO thin films are important for applications such as transparent electromagnetic interference (EMI shielding materials and solar cells. The obtained optical band gap (3.2–3.08 eV was found to be less than pure ZnO (3.37 eV films. The lowering in the band gap in Al:ZnO thin films could be attributed to band edge bending phenomena. The photoluminescence spectra gives sharp visible emission peaks, enables Al:ZnO thin films for light emitting devices (LEDs applications. The current–voltage (I–V measurements show the ohmic behavior of the films with resistivity (ρ~10−3 Ω cm.

  18. Parametric study of thin film evaporation from nanoporous membranes

    Science.gov (United States)

    Wilke, Kyle L.; Barabadi, Banafsheh; Lu, Zhengmao; Zhang, TieJun; Wang, Evelyn N.

    2017-10-01

    The performance and lifetime of advanced electronics are often dictated by the ability to dissipate heat generated within the device. Thin film evaporation from nanoporous membranes is a promising thermal management approach, which reduces the thermal transport distance across the liquid film while also providing passive capillary pumping of liquid to the evaporating interface. In this work, we investigated the dependence of thin film evaporation from nanoporous membranes on a variety of geometric parameters. Anodic aluminum oxide membranes were used as experimental templates, where pore radii of 28-75 nm, porosities of 0.1-0.35, and meniscus locations down to 1 μm within the pore were tested. We demonstrated different heat transfer regimes and observed more than an order of magnitude increase in dissipated heat flux by operating in the pore-level evaporation regime. The pore diameter had little effect on pore-level evaporation performance due to the negligible conduction resistance from the pore wall to the evaporating interface. The dissipated heat flux scaled with porosity as the evaporative area increased. Furthermore, moving the meniscus as little as 1 μm into the pore decreased the dissipated heat flux by more than a factor of two due to the added resistance to vapor escaping the pore. The experimental results elucidate thin film evaporation from nanopores and confirm findings of recent modeling efforts. This work also provides guidance for the design of future thin film evaporation devices for advanced thermal management. Furthermore, evaporation from nanopores is relevant to water purification, chemical separations, microfluidics, and natural processes such as transpiration.

  19. Ion irradiation of AZO thin films for flexible electronics

    Energy Technology Data Exchange (ETDEWEB)

    Boscarino, Stefano; Torrisi, Giacomo; Crupi, Isodiana [IMM-CNR and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania (Italy); Alberti, Alessandra [CNR-IMM, via Strada VIII 5, 95121 Catania (Italy); Mirabella, Salvatore; Ruffino, Francesco [IMM-CNR and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania (Italy); Terrasi, Antonio, E-mail: antonio.terrasi@ct.infn.it [IMM-CNR and Dipartimento di Fisica e Astronomia, Università di Catania, via S. Sofia 64, 95123 Catania (Italy)

    2017-02-01

    Highlights: • Evidence of electrical good quality AZO ultra thin films without thermal annealing. • Evidence of the main role of Oxygen vs. structural parameters in controlling the electrical performances of AZO. • Evidence of the role of the ion irradiation in improving the electrical properties of AZO ultra thin films. • Synthesis of AZO thin films on flexible/plastic substrates with good electrical properties without thermal processes. - Abstract: Aluminum doped Zinc oxide (AZO) is a promising transparent conductor for solar cells, displays and touch-screen technologies. The resistivity of AZO is typically improved by thermal annealing at temperatures not suitable for plastic substrates. Here we present a non-thermal route to improve the electrical and structural properties of AZO by irradiating the TCO films with O{sup +} or Ar{sup +} ion beams (30–350 keV, 3 × 10{sup 15}–3 × 10{sup 16} ions/cm{sup 2}) after the deposition on glass and flexible polyethylene naphthalate (PEN). X-ray diffraction, optical absorption, electrical measurements, Rutherford Backscattering Spectrometry and Atomic Force Microscopy evidenced an increase of the crystalline grain size and a complete relief of the lattice strain upon ion beam irradiation. Indeed, the resistivity of thin AZO films irradiated at room temperature decreased of two orders of magnitude, similarly to a thermal annealing at 400 °C. We also show that the improvement of the electrical properties does not simply depend on the strain or polycrystalline domain size, as often stated in the literature.

  20. Microstructure and opto-electric properties of Cu/ITO thin films

    International Nuclear Information System (INIS)

    Wang Xian; Li Junlei; Shi Shiwei; Song Xueping; Cui Jingbiao; Sun Zhaoqi

    2012-01-01

    Highlights: ► We prepared Cu/ITO films with different Cu layer thickness. ► We analyzed the relation between opto-electric properties and roughness of the films. ► The Cu-16.1 nm/ITO film shows excellent optical and electric properties. ► Cu/ITO films have great application prospects in new-type transflective displays. - Abstract: Cu/ITO thin films were deposited on glass and silicon substrates by DC and RF magnetron sputtering at room temperature. X-ray diffraction results showed that the films were amorphous. Both of SEM images and 3D Profilometer images indicated that the surface morphology of the ITO films had been affected by the Cu layer. The optical and electric properties of the Cu/ITO films changed significantly with the variation of Cu layer thickness. Cu-5.4 nm/ITO film exhibited the highest optical transmittance of 62.9% at 550 nm and the lowest sheet resistance of 96 Ω/□, whereas Cu-16.1 nm/ITO film showed the highest average reflectance of 24.0% and the lowest resistance of 27.4 Ω/□. Based on our analysis, it was evaluated that Cu layer had an important effect on the electrical and optical properties of ITO thin films.

  1. Morphological differences in transparent conductive indium-doped zinc oxide thin films deposited by ultrasonic spray pyrolysis

    International Nuclear Information System (INIS)

    Jongthammanurak, Samerkhae; Cheawkul, Tinnaphob; Witana, Maetapa

    2014-01-01

    In-doped ZnO thin films were deposited on glass substrates by an ultrasonic spray pyrolysis technique, using indium chloride (InCl 3 ) as a dopant and zinc acetate solution as a precursor. Increasing the [at.% In]/[at.% Zn] ratio changed the crystal orientations of thin films, from the (100) preferred orientation in the undoped, to the (101) and (001) preferred orientations in the In-doped ZnO thin films with 4 at.% and 6–8 at.%, respectively. Undoped ZnO thin film shows relatively smooth surface whereas In-doped ZnO thin films with 4 at.% and 6–8 at.% show surface features of pyramidal forms and hexagonal columns, respectively. X-ray diffraction patterns of the In-doped ZnO thin films with [at.% In]/[at.% Zn] ratios of 6–8% presented an additional peak located at 2-theta of 32.95°, which possibly suggested that a metastable Zn 7 In 2 O 10 phase was present with the ZnO phase. ZnO thin films doped with 2 at.% In resulted in a sheet resistance of ∼ 645 Ω/sq, the lowest value among thin films with [at.% In]/[at.% Zn] ratio in a range of 0–8%. The precursor molarity was changed between 0.05 M and 0.20 M at an [at.% In]/[at.% Zn] ratio of 2%. Increasing the precursor molarity in a range of 0.10 M–0.20 M resulted in In-doped ZnO thin films with the (100) preferred orientation. An In-doped ZnO thin film deposited by 0.20 M precursor showed a sheet resistance of 25 Ω/sq, and an optical transmission of 75% at 550 nm wavelength. The optical band gap estimated from the transmission result was 3.292 eV. - Highlights: • Indium-doped ZnO thin films were grown on glass using ultrasonic spray pyrolysis. • Thin films' orientations depend on In doping and Zn molarity of precursor solution. • Highly c-axis or a-axis orientations were found in the In-doped ZnO thin films. • In doping of 6–8 at.% may have resulted in ZnO and a metastable Zn 7 In 2 O 10 phases. • Increasing precursor molarity reduced sheet resistance of In-doped ZnO thin films

  2. Characterization of Alq3 thin films by a near-field microwave microprobe.

    Science.gov (United States)

    Hovsepyan, Artur; Lee, Huneung; Sargsyan, Tigran; Melikyan, Harutyun; Yoon, Youngwoon; Babajanyan, Arsen; Friedman, Barry; Lee, Kiejin

    2008-09-01

    We observed tris-8-hydroxyquinoline aluminum (Alq3) thin films dependence on substrate heating temperatures by using a near-field microwave microprobe (NFMM) and by optical absorption at wavelengths between 200 and 900 nm. The changes of absorption intensity at different substrate heating temperatures are correlated to the changes in the sheet resistance of Alq3 thin films.

  3. NMR characterization of thin films

    Science.gov (United States)

    Gerald II, Rex E.; Klingler, Robert J.; Rathke, Jerome W.; Diaz, Rocio; Vukovic, Lela

    2010-06-15

    A method, apparatus, and system for characterizing thin film materials. The method, apparatus, and system includes a container for receiving a starting material, applying a gravitational force, a magnetic force, and an electric force or combinations thereof to at least the starting material, forming a thin film material, sensing an NMR signal from the thin film material and analyzing the NMR signal to characterize the thin film of material.

  4. NMR characterization of thin films

    Science.gov (United States)

    Gerald, II, Rex E.; Klingler, Robert J.; Rathke, Jerome W.; Diaz, Rocio; Vukovic, Lela

    2008-11-25

    A method, apparatus, and system for characterizing thin film materials. The method, apparatus, and system includes a container for receiving a starting material, applying a gravitational force, a magnetic force, and an electric force or combinations thereof to at least the starting material, forming a thin film material, sensing an NMR signal from the thin film material and analyzing the NMR signal to characterize the thin film of material.

  5. Study of thin films of carrier-doped strontium titanate with emphasis on their interfaces with organic thin films

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Naoki [Laboratory of Molecular Aggregation Analysis, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)]. E-mail: naokis@e.kuicr.kyoto-u.ac.jp; Harada, Youichiro [Laboratory of Molecular Aggregation Analysis, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Terashima, Takahito [International Research Center of Elements Science, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Kanda, Ryoko [International Research Center of Elements Science, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan); Takano, Mikio [International Research Center of Elements Science, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2005-05-15

    Fifty nanometer-thick metal-doped strontium titanate (M:STO, M = La and V) films deposited epitaxially on single crystalline STO substrates were characterized in comparison with indium tin oxide (ITO) covered glasses, to check their applicability to optically transparent anode materials for organic optoelectronic devices. M:STO, in particular V:STO, films turned out to have distinct surface flatness, needfully low electric resistivities and notably large work functions. While their optical transmittances are lower than those of ITOs at this moment, we suggest that M:STO films have a potential to take the place of ITO films. Further, we have observed energy level alignments for copper phthalocyanine thin films at the interface of V:STO.

  6. Shape controlled synthesis of CaMoO4 thin films and their photoluminescence property

    International Nuclear Information System (INIS)

    Marques, Ana Paula de Azevedo; Longo, Valeria M.; Melo, Dulce M.A. de; Pizani, Paulo S.; Leite, Edson R.; Varela, Jose Arana; Longo, Elson

    2008-01-01

    CaMoO 4 (CMO) disordered and ordered thin films were prepared by the complex polymerization method (CPM). The films were annealed at different temperatures and time in a conventional resistive furnace (RF) and in a microwave (MW) oven. The microstructure and surface morphology of the structure were monitored by atomic force microscopy (AFM) and high-resolution scanning electron microscopy (HRSEM). Order and disorder were characterized by X-ray diffraction (XRD) and optical reflectance. A strong photoluminescence (PL) emission was observed in the disordered thin films and was attributed to complex cluster vacancies. The experimental results were compared with density functional and Hartree-Fock calculations. - Graphical abstract: CaMoO 4 thin films were prepared by the complex polymerization method (CPM). The films were annealed at different temperatures and time in a conventional resistive furnace and in a microwave oven. A strong photoluminescence emission was observed in the disordered thin films and was attributed to complex cluster vacancies. The experimental results were confirmed by high level first principle calculations

  7. Optically transparent, mechanically durable, nanostructured superhydrophobic surfaces enabled by spinodally phase-separated glass thin films.

    Science.gov (United States)

    Aytug, Tolga; Simpson, John T; Lupini, Andrew R; Trejo, Rosa M; Jellison, Gerald E; Ivanov, Ilia N; Pennycook, Stephen J; Hillesheim, Daniel A; Winter, Kyle O; Christen, David K; Hunter, Scott R; Haynes, J Allen

    2013-08-09

    We describe the formation and properties of atomically bonded, optical quality, nanostructured thin glass film coatings on glass plates, utilizing phase separation by spinodal decomposition in a sodium borosilicate glass system. Following deposition via magnetron sputtering, thermal processing and differential etching, these coatings are structurally superhydrophilic (i.e., display anti-fogging functionality) and demonstrate robust mechanical properties and superior abrasion resistance. After appropriate chemical surface modification, the surfaces display a stable, non-wetting Cassie-Baxter state and exhibit exceptional superhydrophobic performance, with water droplet contact angles as large as 172°. As an added benefit, in both superhydrophobic and superhydrophilic states these nanostructured surfaces can block ultraviolet radiation and can be engineered to be anti-reflective with broadband and omnidirectional transparency. Thus, the present approach could be tailored toward distinct coatings for numerous markets, such as residential windows, windshields, specialty optics, goggles, electronic and photovoltaic cover glasses, and optical components used throughout the US military.

  8. Optically transparent, mechanically durable, nanostructured superhydrophobic surfaces enabled by spinodally phase-separated glass thin films

    Science.gov (United States)

    Aytug, Tolga; Simpson, John T.; Lupini, Andrew R.; Trejo, Rosa M.; Jellison, Gerald E.; Ivanov, Ilia N.; Pennycook, Stephen J.; Hillesheim, Daniel A.; Winter, Kyle O.; Christen, David K.; Hunter, Scott R.; Haynes, J. Allen

    2013-08-01

    We describe the formation and properties of atomically bonded, optical quality, nanostructured thin glass film coatings on glass plates, utilizing phase separation by spinodal decomposition in a sodium borosilicate glass system. Following deposition via magnetron sputtering, thermal processing and differential etching, these coatings are structurally superhydrophilic (i.e., display anti-fogging functionality) and demonstrate robust mechanical properties and superior abrasion resistance. After appropriate chemical surface modification, the surfaces display a stable, non-wetting Cassie-Baxter state and exhibit exceptional superhydrophobic performance, with water droplet contact angles as large as 172°. As an added benefit, in both superhydrophobic and superhydrophilic states these nanostructured surfaces can block ultraviolet radiation and can be engineered to be anti-reflective with broadband and omnidirectional transparency. Thus, the present approach could be tailored toward distinct coatings for numerous markets, such as residential windows, windshields, specialty optics, goggles, electronic and photovoltaic cover glasses, and optical components used throughout the US military.

  9. Optically transparent, mechanically durable, nanostructured superhydrophobic surfaces enabled by spinodally phase-separated glass thin films

    International Nuclear Information System (INIS)

    Aytug, Tolga; Simpson, John T; Lupini, Andrew R; Trejo, Rosa M; Jellison, Gerald E; Ivanov, Ilia N; Pennycook, Stephen J; Hillesheim, Daniel A; Winter, Kyle O; Christen, David K; Hunter, Scott R; Allen Haynes, J

    2013-01-01

    We describe the formation and properties of atomically bonded, optical quality, nanostructured thin glass film coatings on glass plates, utilizing phase separation by spinodal decomposition in a sodium borosilicate glass system. Following deposition via magnetron sputtering, thermal processing and differential etching, these coatings are structurally superhydrophilic (i.e., display anti-fogging functionality) and demonstrate robust mechanical properties and superior abrasion resistance. After appropriate chemical surface modification, the surfaces display a stable, non-wetting Cassie–Baxter state and exhibit exceptional superhydrophobic performance, with water droplet contact angles as large as 172°. As an added benefit, in both superhydrophobic and superhydrophilic states these nanostructured surfaces can block ultraviolet radiation and can be engineered to be anti-reflective with broadband and omnidirectional transparency. Thus, the present approach could be tailored toward distinct coatings for numerous markets, such as residential windows, windshields, specialty optics, goggles, electronic and photovoltaic cover glasses, and optical components used throughout the US military. (paper)

  10. Characterization of CuS nanocrystalline thin films synthesized by chemical bath deposition and dip coating techniques

    International Nuclear Information System (INIS)

    Chaki, Sunil H.; Deshpande, M.P.; Tailor, Jiten P.

    2014-01-01

    CuS thin films were synthesized by chemical bath deposition and dip coating techniques at ambient temperature. The energy dispersive analysis of X-rays of the thin films confirmed that both the as synthesized thin films are stoichiometric. The X-ray diffraction of the chemical bath deposited and dip coating deposited thin films showed that the films possess hexagonal structure having lattice parameters, a = b = 3.79 A and c = 16.34 A. The crystallite sizes determined from the X-ray diffraction data using Scherrer's formula for the chemical bath deposition and dip coating deposition thin films came out to be nearly 11 nm and 13 nm, respectively. The optical microscopy of the as deposited thin films surfaces showed that the substrates are well covered in both the deposited films. The scanning electron microscopy of the thin films clearly showed that in chemical bath deposited thin films the grain size varies from few μm to nm, while in dip coating deposited films the grain size ranges in nm. The optical bandgap determined from the optical absorbance spectrum analysis showed, chemical bath deposited thin films possess direct bandgap of 2.2 eV and indirect bandgap of 1.8 eV. In the case of dip coating deposited thin films, the direct bandgap is 2.5 eV and indirect bandgap is 1.9 eV. The d.c. electrical resistivity variation with temperature for both the deposited films showed that the resistivity decreases with temperature thus confirming the semiconducting nature. The thermoelectric power variations with temperature and the room temperature Hall Effect study of both the synthesized CuS thin films showed them to be of p-type conductivity. The obtained results are discussed in details. - Highlights: • CuS thin films were synthesized by chemical bath deposition and dip coating techniques. • The films possessed hexagonal structure. • The optical absorption showed that the films had direct and indirect bandgap. • Study of electrical transport properties

  11. Handbook of thin film technology

    CERN Document Server

    Frey, Hartmut

    2015-01-01

    “Handbook of Thin Film Technology” covers all aspects of coatings preparation, characterization and applications. Different deposition techniques based on vacuum and plasma processes are presented. Methods of surface and thin film analysis including coating thickness, structural, optical, electrical, mechanical and magnetic properties of films are detailed described. The several applications of thin coatings and a special chapter focusing on nanoparticle-based films can be found in this handbook. A complete reference for students and professionals interested in the science and technology of thin films.

  12. Chemical mechanical polishing characteristics of ITO thin film prepared by RF magnetron sputtering

    International Nuclear Information System (INIS)

    Lee, Kang-Yeon; Choi, Gwon-Woo; Kim, Yong-Jae; Choi, Youn-Ok; Kim, Nam-Oh

    2012-01-01

    Indium-tin-oxide (ITO) thin films have attracted intensive interest because of their unique properties of good conductivity, high optical transmittance over the visible region and easy patterning ability. ITO thin films have found many applications in anti-static coatings, thermal heaters, solar cells, flat panel displays (FPDs), liquid crystal displays (LCDs), electroluminescent devices, sensors and organic light-emitting diodes (OLEDs). ITO thin films are generally fabricated by using various methods, such as spraying, chemical vapor deposition (CVD), evaporation, electron gun deposition, direct current electroplating, high frequency sputtering, and reactive sputtering. In this research, ITO films were grown on glass substrates by using a radio-frequency (RF) magnetron sputtering method. In order to achieve a high transmittance and a low resistivity, we examined the various film deposition conditions, such as substrate temperature, working pressure, annealing temperature, and deposition time. Next, in order to improve the surface quality of the ITO thin films, we performed a chemical mechanical polishing (CMP) with different process parameters and compared the electrical and the optical properties of the polished ITO thin films. The best CMP conditions with a high removal rate, low nonuniformity, low resistivity and high transmittance were as follows: platen speed, head speed, polishing time, and slurry flow rate of 30 rpm, 30 rpm, 60 sec, and 60 ml/min, respectively.

  13. The role of Ar plasma treatment in generating oxygen vacancies in indium tin oxide thin films prepared by the sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Deuk-Kyu [Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seoul, 03722 (Korea, Republic of); Misra, Mirnmoy; Lee, Ye-Eun [Department of BioNano Technology, Gachon University, 1342 Seong-nam dae-ro, Seong-nam si, Gyeonggi-do, 13120 (Korea, Republic of); Baek, Sung-Doo [Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seoul, 03722 (Korea, Republic of); Myoung, Jae-Min, E-mail: jmmyoung@yonsei.ac.kr [Department of Materials Science and Engineering, Yonsei University, 50 Yonsei-ro, Seoul, 03722 (Korea, Republic of); Lee, Tae Il, E-mail: t2.lee77@gachon.ac.kr [Department of BioNano Technology, Gachon University, 1342 Seong-nam dae-ro, Seong-nam si, Gyeonggi-do, 13120 (Korea, Republic of)

    2017-05-31

    Highlights: • Indium tin oxide thin film with about 41 nm thickness was obtained by the sol-gel process. • Thin film exhibited low resistivity. • Sheet resistance of thin film decreases with Ar plasma treatment time. • Ar plasma treatment on thin film does not alter the crystal structure and optical properties of the ITO thin-film. • There is no significant change in oxygen vacancies after 20 min of plasma treatment. - Abstract: Argon (Ar) plasma treatment was carried out to reduce the sheet resistance of indium tin oxide (ITO) thin films. The Ar plasma treatment did not cause any significant changes to the crystal structure, surface morphology, or optical properties of the ITO thin films. However, an X-ray photoelectron spectroscopy study confirmed that the concentration of oxygen vacancies in the film dramatically increased with the plasma treatment time. Thus, we concluded that the decrease in the sheet resistance was caused by the increase in the oxygen vacancy concentration in the film. Furthermore, to verify how the concentration of oxygen vacancies in the film increased with the Ar plasma treatment time, cumulative and continuous plasma treatments were conducted. The oxygen vacancies were found to be created by surface heating via the outward thermal diffusion of oxygen atoms from inside the film.

  14. Resistivity Effects of Cation Ordering in Highly-Doped La2-xSrxCu4 Epitaxial Thin Films

    Science.gov (United States)

    Burquest, Franklin; Marmol, Rodrigo; Cox, Nicholas; Nelson-Cheeseman, Brittany

    Highly-doped La2-xSrxCuO4 (LSCO) films (0.5 causes internal polar electrostatic forces, which have been shown to cause stretching of the apical oxygen bond in analogous epitaxial nickelate films. Thin film samples are grown concurrently to minimize extraneous effects on film structure and properties. Atomic force microscopy and x-ray reflectivity demonstrate that the films are single crystalline, epitaxial, and smooth. X-ray diffraction is used to measure the c-axis of the films as a function of doping and dopant cation ordering. Electrical transport data of the ordered samples is compared with transport data of conventional disordered cation samples. Preliminary data indicates significant differences in resistivity at both 300K and 10K between the cation-ordered and cation-disordered samples. This work indicates that dopant cation ordering within the layered cuprates could significantly modify the conduction mechanisms at play in these materials.

  15. Applying RF Magnetron sputtering to prepare ZnO thin films and their characterization

    International Nuclear Information System (INIS)

    Saad, M.; Kassis, A.

    2009-05-01

    ZnO thin films were prepared using Rf magnetron sputtering under several preparation conditions (different values of deposition pressure, Rf power, substrate temperature). The optical properties of these films were investigated by measuring their transmission in the spectral range (300-1000 nm), and the electrical properties were investigated by measuring their electrical resistance. Results have been discussed in terms of the modified Thornton model for sputtered thin metal oxide films. Preparation conditions for depositing the highly resistive transparent i-ZnO buffer layer and the highly conducting transparent n-ZnO window layer for solar cells were proposed. (author)

  16. ITO thin films deposited by advanced pulsed laser deposition

    International Nuclear Information System (INIS)

    Viespe, Cristian; Nicolae, Ionut; Sima, Cornelia; Grigoriu, Constantin; Medianu, Rares

    2007-01-01

    Indium tin oxide thin films were deposited by computer assisted advanced PLD method in order to obtain transparent, conductive and homogeneous films on a large area. The films were deposited on glass substrates. We studied the influence of the temperature (room temperature (RT)-180 deg. C), pressure (1-6 x 10 -2 Torr), laser fluence (1-4 J/cm 2 ) and wavelength (266-355 nm) on the film properties. The deposition rate, roughness, film structure, optical transmission, electrical conductivity measurements were done. We deposited uniform ITO thin films (thickness 100-600 nm, roughness 5-10 nm) between RT and 180 deg. C on a large area (5 x 5 cm 2 ). The films have electrical resistivity of 8 x 10 -4 Ω cm at RT, 5 x 10 -4 Ω cm at 180 deg. C and an optical transmission in the visible range, around 89%

  17. Rare Earth Oxide Thin Films

    CERN Document Server

    Fanciulli, Marco

    2007-01-01

    Thin rare earth (RE) oxide films are emerging materials for microelectronic, nanoelectronic, and spintronic applications. The state-of-the-art of thin film deposition techniques as well as the structural, physical, chemical, and electrical properties of thin RE oxide films and of their interface with semiconducting substrates are discussed. The aim is to identify proper methodologies for the development of RE oxides thin films and to evaluate their effectiveness as innovative materials in different applications.

  18. Thin-film solar cells

    International Nuclear Information System (INIS)

    Aberle, Armin G.

    2009-01-01

    The rapid progress that is being made with inorganic thin-film photovoltaic (PV) technologies, both in the laboratory and in industry, is reviewed. While amorphous silicon based PV modules have been around for more than 20 years, recent industrial developments include the first polycrystalline silicon thin-film solar cells on glass and the first tandem solar cells based on stacks of amorphous and microcrystalline silicon films ('micromorph cells'). Significant thin-film PV production levels are also being set up for cadmium telluride and copper indium diselenide.

  19. Optical and Electrical Properties of Copper Oxide Thin Films Synthesized by Spray Pyrolysis Technique

    Directory of Open Access Journals (Sweden)

    S. S. Roy

    2015-08-01

    Full Text Available Copper oxide (CuO thin films have been synthesized on to glass substrates at different temperatures in the range 250-450 °C by spray pyrolysis technique from aqueous solution using cupric acetate Cu(CH3COO2·H2O as a precursor. The structure of the deposited CuO thin films characterized by X-ray diffraction, the surface morphology was observed by a scanning electron microscope, the presence of elements was detected by energy dispersive X-ray analysis, the optical transmission spectra was recorded by ultraviolet-visible spectroscopy and electrical resistivity was studied by Van-der Pauw method. All the CuO thin films, irrespective of growth temperature, showed a monoclinic structure with the main CuO (111 orientation, and the crystallite size was about 8.4784 Å for the thin film synthesized at 350 °C. The optical transmission of the as-deposited film is found to decrease with the increase of substrate temperature, the optical band gap of the thin films varies from 1.90 to 1.60 eV and the room temperature electrical resistivity varies from 30 to18 Ohm·cm for the films grown at different substrate temperatures.

  20. Process for forming thin film, heat treatment process of thin film sheet, and heat treatment apparatus therefor

    International Nuclear Information System (INIS)

    Watanabe, S.

    1984-01-01

    The invention provides a process for forming a magnetic thin film on a base film, a heat treatment process of a thin film sheet consisting of the base film and the magnetic thin film, and an apparatus for performing heat treatment of the thin film sheet. Tension applied to the thin film sheet is substantially equal to that applied to the base film when the magnetic thin film is formed thereon. Then, the thin film sheet is treated with heat. The thin film sheet is heated with a given temperature gradient to a reactive temperature at which heat shrinkage occurs, while the tension is being applied thereto. Thereafter, the thin film sheet to which the tension is still applied is cooled with substantially the same temperature gradient as applied in heating. The heat treatment apparatus has a film driving unit including a supply reel, a take-up reel, a drive source and guide rollers; a heating unit including heating plates, heater blocks and a temperature controller for heating the sheet to the reactive temperature; and a heat insulating unit including a thermostat and another temperature controller for maintaining the sheet at the nonreactive temperature which is slightly lower than the reactive temperature

  1. Alkaline-doped manganese perovskite thin films grown by MOCVD

    International Nuclear Information System (INIS)

    Bibes, M.; Gorbenko, O.; Martinez, B.; Kaul, A.; Fontcuberta, J.

    2000-01-01

    We report on the preparation and characterization of La 1-x Na x MnO 3 thin films grown by MOCVD on various single-crystalline substrates. Under appropriate conditions epitaxial thin films have been obtained. The Curie temperatures of the films, which are very similar to those of bulk samples of similar composition, reflect the residual strain caused by the substrate. The anisotropic magnetoresistance AMR of the films has been analyzed in some detail, and it has been found that it has a two-fold symmetry at any temperature. Its temperature dependence mimics that of the electrical resistivity and magnetoresistance measured at similar fields, thus suggesting that the real structure of the material contributes to the measured AMR besides the intrinsic component

  2. Low resistance polycrystalline diamond thin films deposited by hot ...

    Indian Academy of Sciences (India)

    Administrator

    silicon wafers using a hydrocarbon gas (CH4) highly diluted with H2 at low pressure in a hot filament chemi- cal vapour ... the laser spot was focused on the sample surface using a ... tative spectra of diamond thin films with a typical dia-.

  3. Improved ITO thin films for photovoltaic applications with a thin ZnO layer by sputtering

    International Nuclear Information System (INIS)

    Herrero, J.; Guillen, C.

    2004-01-01

    The improvement of the optical and electrical characteristics of indium tin oxide (ITO) layers is pursued to achieve a higher efficiency in its application as frontal electrical contacts in thin film photovoltaic devices. In order to take advantage of the polycrystalline structure of ZnO films as growth support, the properties of ITO layers prepared at room temperature by sputtering onto bare and ZnO-coated substrates have been analyzed using X-ray diffraction, optical and electrical measurements. It has been found that by inserting a thin ZnO layer, the ITO film resistivity can be reduced as compared to that of a single ITO film with similar optical transmittance. The electrical quality improvement is related to ITO grain growth enhancement onto the polycrystalline ZnO underlayer

  4. Deposition and characterization of NbAIN thin films by reactive magnetron sputtering

    International Nuclear Information System (INIS)

    Carvalho, R.G.; Felix, L.C.; Fernandez, D.A.R.; Fontes Junior, A.S.; Oliveira, G.B.; Tentardini, E.K.

    2016-01-01

    The objective of this work was to study NbAlN thin films and the influence of variation in the concentration of aluminum in the crystal structure and oxidation resistance of these coatings. The thin films were deposited by reactive magnetron sputtering and characterized by Grazing Incidence X-ray Diffraction (GIXRD), Energy Dispersive Spectroscopy (EDS) and oxidation tests at high temperatures. NbAlN thin films were deposited and present at concentration of 10, 20 and 42 at% Al. The NbAlN crystalline phase obtained was the δ-NbN, however it was observed a shift of the peaks in the patterns obtained GIXRD of regions for larger angles for these samples, indicating the formation of a solid solution. The higher oxidation resistance temperature was 700° C for the sample with 42 in at% Al. From the SEM analysis it was possible to observe the surface of the film after oxidation, all films showed defects, however the amount of such defects was lower in samples with higher aluminum concentrations. (author)

  5. Title: Using Alignment and 2D Network Simulations to Study Charge Transport Through Doped ZnO Nanowire Thin Film Electrodes

    KAUST Repository

    Phadke, Sujay

    2011-09-30

    Factors affecting charge transport through ZnO nanowire mat films were studied by aligning ZnO nanowires on substrates and coupling experimental measurements with 2D nanowire network simulations. Gallium doped ZnO nanowires were aligned on thermally oxidized silicon wafer by shearing a nanowire dispersion in ethanol. Sheet resistances of nanowire thin films that had current flowing parallel to nanowire alignment direction were compared to thin films that had current flowing perpendicular to nanowire alignment direction. Perpendicular devices showed ∼5 fold greater sheet resistance than parallel devices supporting the hypothesis that aligning nanowires would increase conductivity of ZnO nanowire electrodes. 2-D nanowire network simulations of thin films showed that the device sheet resistance was dominated by inter-wire contact resistance. For a given resistivity of ZnO nanowires, the thin film electrodes would have the lowest possible sheet resistance if the inter-wire contact resistance was one order of magnitude lower than the single nanowire resistance. Simulations suggest that the conductivity of such thin film devices could be further enhanced by using longer nanowires. Solution processed Gallium doped ZnO nanowires are aligned on substrates using an innovative shear coating technique. Nanowire alignment has shown improvement in ZnO nanowire transparent electrode conductivity. 2D network simulations in conjunction with electrical measurements have revealed different regimes of operation of nanowire thin films and provided a guideline for improving electrical performance of nanowire electrodes. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Characterization of nanostructured photosensitive cadmium sulphide thin films grown by SILAR deposition technique

    International Nuclear Information System (INIS)

    Ubale, A.U.; Bargal, A.N.

    2010-01-01

    This paper reports the preparation of photosensitive nanostructured CdS thin films by successive ionic layer adsorption and reaction (SILAR) method at room temperature. To obtain good quality CdS thin films, preparative conditions such as concentration of cationic and anionic precursors, adsorption and rinsing time durations etc. are optimized. The structural, optical and electrical characterizations of the as-deposited and annealed CdS thin films were carried out using X-ray diffraction, scanning electron microscopy, optical absorption and electrical resistivity methods. The photoconductivity studies showed that the annealed films are more than that photosensitive. The TEP measurement shows that deposited films are of n-type. (author)

  7. Mesoscopic Percolating Resistance Network in a Strained Manganite Thin Film

    KAUST Repository

    Lai, K.; Nakamura, M.; Kundhikanjana, W.; Kawasaki, M.; Tokura, Y.; Kelly, M. A.; Shen, Z.-X.

    2010-01-01

    Many unusual behaviors in complex oxides are deeply associated with the spontaneous emergence of microscopic phase separation. Depending on the underlying mechanism, the competing phases can form ordered or random patterns at vastly different length scales. By using a microwave impedance microscope, we observed an orientation-ordered percolating network in strained Nd 1/2Sr1/2MnO3 thin films with a large period of 100 nanometers. The filamentary metallic domains align preferentially along certain crystal axes of the substrate, suggesting the anisotropic elastic strain as the key interaction in this system. The local impedance maps provide microscopic electrical information of the hysteretic behavior in strained thin film manganites, suggesting close connection between the glassy order and the colossal magnetoresistance effects at low temperatures.

  8. Mesoscopic Percolating Resistance Network in a Strained Manganite Thin Film

    KAUST Repository

    Lai, K.

    2010-07-08

    Many unusual behaviors in complex oxides are deeply associated with the spontaneous emergence of microscopic phase separation. Depending on the underlying mechanism, the competing phases can form ordered or random patterns at vastly different length scales. By using a microwave impedance microscope, we observed an orientation-ordered percolating network in strained Nd 1/2Sr1/2MnO3 thin films with a large period of 100 nanometers. The filamentary metallic domains align preferentially along certain crystal axes of the substrate, suggesting the anisotropic elastic strain as the key interaction in this system. The local impedance maps provide microscopic electrical information of the hysteretic behavior in strained thin film manganites, suggesting close connection between the glassy order and the colossal magnetoresistance effects at low temperatures.

  9. Mesoscopic percolating resistance network in a strained manganite thin film.

    Science.gov (United States)

    Lai, Keji; Nakamura, Masao; Kundhikanjana, Worasom; Kawasaki, Masashi; Tokura, Yoshinori; Kelly, Michael A; Shen, Zhi-Xun

    2010-07-09

    Many unusual behaviors in complex oxides are deeply associated with the spontaneous emergence of microscopic phase separation. Depending on the underlying mechanism, the competing phases can form ordered or random patterns at vastly different length scales. By using a microwave impedance microscope, we observed an orientation-ordered percolating network in strained Nd(1/2)Sr(1/2)MnO3 thin films with a large period of 100 nanometers. The filamentary metallic domains align preferentially along certain crystal axes of the substrate, suggesting the anisotropic elastic strain as the key interaction in this system. The local impedance maps provide microscopic electrical information of the hysteretic behavior in strained thin film manganites, suggesting close connection between the glassy order and the colossal magnetoresistance effects at low temperatures.

  10. Predicting the Abrasion Resistance of Tool Steels by Means of Neurofuzzy Model

    Directory of Open Access Journals (Sweden)

    Dragutin Lisjak

    2013-07-01

    Full Text Available This work considers use neurofuzzy set theory for estimate abrasion wear resistance of steels based on chemical composition, heat treatment (austenitising temperature, quenchant and tempering temperature, hardness after hardening and different tempering temperature and volume loss of materials according to ASTM G 65-94. Testing of volume loss for the following group of materials as fuzzy data set was taken: carbon tool steels, cold work tool steels, hot work tools steels, high-speed steels. Modelled adaptive neuro fuzzy inference system (ANFIS is compared to statistical model of multivariable non-linear regression (MNLR. From the results it could be concluded that it is possible well estimate abrasion wear resistance for steel whose volume loss is unknown and thus eliminate unnecessary testing.

  11. Influence of Utilization of High-Volumes of Class F Fly Ash on the Abrasion Resistance of Concrete

    Directory of Open Access Journals (Sweden)

    William PRINCE

    2007-01-01

    Full Text Available Utilization of large volumes of fly ash in various concrete applications is a becoming a more general practice in an efforts towards using large quantities of fly ash. Around the world, Class C or Class F or both as available have been used in high volumes in cement-based materials. In India, majority of fly generated is of Class F type as per ASTM C 618. Yearly fly ash generation in India is approximately 95 million tonnes. Out of which around 15-20% is utilized in cement production and cement/concrete related activities. In order to increase its percentage utilization, an investigation was carried out to use it in concrete.In this paper, abrasion resistance of high volume fly ash (HVFA concretes made with 35, 45, 55, and 65% of cement replacement was evaluated in terms of its relation with compressive strength. Comparison was made between ordinary Portland cement and fly ash concrete. Test results indicated that abrasion resistance of concrete having cement replacement up to 35 percent was comparable to the normal concrete mix with out fly ash. Beyond 35% cement replacement, fly ash concretes exhibited slightly lower resistance to abrasion relative to non-fly ash concretes. Test results further indicated that abrasion resistance of concrete is closely related with compressive strength, and had a very good correlation between abrasion resistance and compressive strength (R2 value between 0.9018 and 0.9859 depending upon age.

  12. Ion beam-based characterization of multicomponent oxide thin films and thin film layered structures

    International Nuclear Information System (INIS)

    Krauss, A.R.; Rangaswamy, M.; Lin, Yuping; Gruen, D.M.; Schultz, J.A.; Schmidt, H.K.; Chang, R.P.H.

    1992-01-01

    Fabrication of thin film layered structures of multi-component materials such as high temperature superconductors, ferroelectric and electro-optic materials, and alloy semiconductors, and the development of hybrid materials requires understanding of film growth and interface properties. For High Temperature Superconductors, the superconducting coherence length is extremely short (5--15 Angstrom), and fabrication of reliable devices will require control of film properties at extremely sharp interfaces; it will be necessary to verify the integrity of thin layers and layered structure devices over thicknesses comparable to the atomic layer spacing. Analytical techniques which probe the first 1--2 atomic layers are therefore necessary for in-situ characterization of relevant thin film growth processes. However, most surface-analytical techniques are sensitive to a region within 10--40 Angstrom of the surface and are physically incompatible with thin film deposition and are typically restricted to ultra high vacuum conditions. A review of ion beam-based analytical methods for the characterization of thin film and multi-layered thin film structures incorporating layers of multicomponent oxides is presented. Particular attention will be paid to the use of time-of-flight techniques based on the use of 1- 15 key ion beams which show potential for use as nondestructive, real-time, in-situ surface diagnostics for the growth of multicomponent metal and metal oxide thin films

  13. Electric Transport Phenomena of Nanocomposite Organic Polymer Thin Films

    Science.gov (United States)

    Jira, Nicholas C.; Sabirianov, Ildar; Ilie, Carolina C.

    We discuss herein the nanocomposite organic thin film diodes for the use of plasmonic solar cells. This experimental work follows the theoretical calculations done for plasmonic solar cells using the MNPBEM toolbox for MatLab. These calculations include dispersion curves and amount of light scattering cross sections for different metallic nanoparticles. This study gives us clear ideas on what to expect from different metals, allowing us to make the best choice on what to use to obtain the best results. One specific technique for light trapping in thin films solar cells utilizes metal nanoparticles on the surface of the semiconductor. The characteristics of the metal, semiconductor interface allows for light to be guided in between them causing it to be scattered, allowing for more chances of absorption. The samples were fabricated using organic thin films made from polymers and metallic nanoparticles, more specifically Poly(1-vinylpyrrolidone-co-2-dimethylaminoethyl methacrylate) copolymer and silver or gold nanoparticles. The two fabrication methods applied include spin coating and Langmuir-Blodgett technique. The transport properties are obtained by analyzing the I-V curves. We will also discuss the resistance, resistivity, conductance, density of charge carriers. SUNY Oswego SCAC Grant.

  14. Uniaxial stress influence on electrical conductivity of thin epitaxial lanthanum-strontium manganite films

    Energy Technology Data Exchange (ETDEWEB)

    Stankevič, V., E-mail: wstan@pfi.lt [Center for Physical Sciences and Technology, Semiconductor Physics Institute, A.Gostauto 11, Vilnius (Lithuania); Vilnius Gediminas Technical University, Sauletekio 11, Vilnius (Lithuania); Šimkevičius, Č.; Balevičius, S.; Žurauskienė, N. [Center for Physical Sciences and Technology, Semiconductor Physics Institute, A.Gostauto 11, Vilnius (Lithuania); Vilnius Gediminas Technical University, Sauletekio 11, Vilnius (Lithuania); Cimmperman, P. [Center for Physical Sciences and Technology, Semiconductor Physics Institute, A.Gostauto 11, Vilnius (Lithuania); Abrutis, A. [Vilnius University, Dept. of General and Inorganic Chemistry, Naugarduko 24, Vilnius (Lithuania); Plaušinaitienė, V. [Center for Physical Sciences and Technology, Semiconductor Physics Institute, A.Gostauto 11, Vilnius (Lithuania); Vilnius University, Dept. of General and Inorganic Chemistry, Naugarduko 24, Vilnius (Lithuania)

    2013-07-01

    This is a study of the influence of external uniaxial mechanical strains on the transport properties of thin epitaxial La{sub 0.83}Sr{sub 0.17}MnO{sub 3} (LSMO) films. Our measurements were carried out using standard isosceles triangle-shaped cantilever. Films which were tensed in-plane or compressed or were subjected to both tension and compression strains were grown onto SrTiO{sub 3} (STO), LaAlO{sub 3} (LAO) and (001) NdGaO{sub 3} (NGO) substrates, respectively. It was found that for thin films (less than 100 nm), the uniaxial compression of such films which were initially tensed in-plane (grown onto STO substrates) produces a decrease of their resistance, whereas the compression of initially compressed films (on LAO substrates) produces an increase of the films' resistance. The same results were obtained for LSMO films grown onto (001) NGO substrates when they were compressed along the [010] and [100] directions, respectively. For thicker films (more than 100 nm), the resistance behavior after uniaxial compression was found to be identical to that produced by hydrostatic compression, namely, the resistance decreases irrespective of the substrate. These experiments also reveal an increase of resistance and a shift of metal–insulator transition temperature T{sub m} to lower temperatures corresponding to a decrease of the film thickness. The occurrence of this effect is also independent of the kind of substrate used. Thus it was concluded that the influence of film thickness on its resistance as well as on the behavior of such films while under external uniaxial compression cannot be explained fully by only the presence of residual stress in these films. A possible reason is that the inhomogeneous distribution of the mechanical stresses in the films can lead to the appearance of two conductivity phases, each having a different mechanism. The results which were obtained when these films were subjected to hydrostatic compression were also explained by this

  15. Ni-Cr thin film resistor fabrication for GaAs monolithic microwave integrated circuits

    International Nuclear Information System (INIS)

    Vinayak, Seema; Vyas, H.P.; Muraleedharan, K.; Vankar, V.D.

    2006-01-01

    Different Ni-Cr alloys were sputter-deposited on silicon nitride-coated GaAs substrates and covered with a spin-coated polyimide layer to develop thin film metal resistors for GaAs monolithic microwave integrated circuits (MMICs). The contact to the resistors was made through vias in the polyimide layer by sputter-deposited Ti/Au interconnect metal. The variation of contact resistance, sheet resistance (R S ) and temperature coefficient of resistance (TCR) of the Ni-Cr resistors with fabrication process parameters such as polyimide curing thermal cycles and surface treatment given to the wafer prior to interconnect metal deposition has been studied. The Ni-Cr thin film resistors exhibited lower R S and higher TCR compared to the as-deposited Ni-Cr film that was not subjected to thermal cycles involved in the MMIC fabrication process. The change in resistivity and TCR values of Ni-Cr films during the MMIC fabrication process was found to be dependent on the Ni-Cr alloy composition

  16. High efficiency copper indium gallium diselenide (CIGS) thin film solar cells

    Science.gov (United States)

    Rajanikant, Ray Jayminkumar

    The generation of electrical current from the solar radiation is known as the photovoltaic effect. Solar cell, also known as photovoltaic (PV) cell, is a device that works on the principle of photovoltaic effect, and is widely used for the generation of electricity. Thin film polycrystalline solar cells based on copper indium gallium diselenide (CIGS) are admirable candidates for clean energy production with competitive prices in the near future. CIGS based polycrystalline thin film solar cells with efficiencies of 20.3 % and excellent temperature stability have already been reported at the laboratory level. The present study discusses about the fabrication of CIGS solar cell. Before the fabrication part of CIGS solar cell, a numerical simulation is carried out using One-Dimensional Analysis of Microelectronic and Photonic Structures (AMPS-ID) for understanding the physics of a solar cell device, so that an optimal structure is analyzed. In the fabrication part of CIGS solar cell, Molybdenum (Mo) thin film, which acts as a 'low' resistance metallic back contact, is deposited by RF magnetron sputtering on organically cleaned soda lime glass substrate. The major advantages for using Mo are high temperature, (greater than 600 °C), stability and inertness to CIGS layer (i.e., no diffusion of CIGS into Mo). Mo thin film is deposited at room temperature (RT) by varying the RF power and the working pressure. The Mo thin films deposited with 100 W RF power and 1 mTorr working pressure show a reflectivity of above average 50 % and the low sheet resistance of about 1 O/□. The p-type CIGS layer is deposited on Mo. Before making thin films of CIGS, a powder of CIGS material is synthesized using melt-quenching method. Thin films of CIGS are prepared by a single-stage flash evaporation process on glass substrates, initially, for optimization of deposition parameters and than on Mo coated glass substrates for device fabrication. CIGS thin film is deposited at 250 °C at a

  17. Influence of standing-wave electric field pattern on the laser damage resistance of HfO sub 2 thin films

    CERN Document Server

    Protopapa, M L; De Tomasi, F; Di Giulio, M; Perrone, M R; Scaglione, S

    2002-01-01

    The standing-wave electric field pattern that forms inside an optical coating as a consequence of laser irradiation is one of the factors influencing the coating laser-induced damage threshold. The influence of the standing-wave electric field profile on the damage resistance to ultraviolet radiation of hafnium dioxide (HfO sub 2) thin films was investigated in this work. To this end, HfO sub 2 thin films of different thicknesses deposited by the electron beam evaporation technique at the same deposition conditions were analyzed. Laser damage thresholds of the samples were measured at 308 nm (XeCl laser) by the photoacoustic beam deflection technique and microscopic inspections. The dependence of the laser damage threshold on the standing-wave electric field pattern was analyzed.

  18. DC Magnetron Sputtered IZTO Thin Films for Organic Photovoltaic Application.

    Science.gov (United States)

    Lee, Hye Ji; Noviyana, Imas; Putri, Maryane; Koo, Chang Young; Lee, Jung-A; Kim, Jeong-Joo; Jeong, Youngjun; Lee, Youngu; Lee, Hee Young

    2018-02-01

    IZTO20 (In0.6Zn0.2Sn0.2O1.5) ceramic target was prepared from oxide mixture of In2O3, ZnO, and SnO2 powders. IZTO20 thin films were then deposited onto glass substrate at 400 °C by DC magnetron sputtering. The average optical transmittance determined by ultraviolet-visible spectroscopy was higher than 85% for all films. The minimum resistivity of the annealed IZTO20 thin film was approximately 6.1×10-4 Ω·cm, which tended to increase with decreasing indium content. Substrate heating and annealing were found to be important parameters affecting the electrical and optical properties. An organic photovoltaic (OPV) cell was fabricated using the IZTO20 film deposited under the optimized condition as an anode electrode and the efficiency of up to 80% compared to that of a similar OPV cell using ITO film was observed. Reduction of surface roughness and electrical resistivity through annealing treatment was found to contribute to the improved efficiency of the OPV cell.

  19. Electroresistance Effect in Gold Thin Film Induced by Ionic-Liquid-Gated Electric Double Layer

    NARCIS (Netherlands)

    Nakayama, Hiroyasu; Ye, Jianting; Ohtani, Takashi; Fujikawa, Yasunori; Ando, Kazuya; Iwasa, Yoshihiro; Saitoh, Eiji

    Electroresistance effect was detected in a metallic thin film using ionic-liquid-gated electric-double-layer transistors (EDLTs). We observed reversible modulation of the electric resistance of a Au thin film. In this system, we found that an electric double layer works as a nanogap capacitor with

  20. Surface scattering mechanisms of tantalum nitride thin film resistor.

    Science.gov (United States)

    Chen, Huey-Ru; Chen, Ying-Chung; Chang, Ting-Chang; Chang, Kuan-Chang; Tsai, Tsung-Ming; Chu, Tian-Jian; Shih, Chih-Cheng; Chuang, Nai-Chuan; Wang, Kao-Yuan

    2014-01-01

    In this letter, we utilize an electrical analysis method to develop a TaN thin film resistor with a stricter spec and near-zero temperature coefficient of resistance (TCR) for car-used electronic applications. Simultaneously, we also propose a physical mechanism mode to explain the origin of near-zero TCR for the TaN thin film resistor (TFR). Through current fitting, the carrier conduction mechanism of the TaN TFR changes from hopping to surface scattering and finally to ohmic conduction for different TaN TFRs with different TaN microstructures. Experimental data of current-voltage measurement under successive increasing temperature confirm the conduction mechanism transition. A model of TaN grain boundary isolation ability is eventually proposed to influence the carrier transport in the TaN thin film resistor, which causes different current conduction mechanisms.

  1. Thermal Stability of Copper-Aluminum Alloy Thin Films for Barrierless Copper Metallization on Silicon Substrate

    Science.gov (United States)

    Wang, C. P.; Dai, T.; Lu, Y.; Shi, Z.; Ruan, J. J.; Guo, Y. H.; Liu, X. J.

    2017-08-01

    Copper thin films with thickness of about 500 nm doped with different aluminum concentrations have been prepared by magnetron sputtering on Si substrate and their crystal structure, microstructure, and electrical resistivity after annealing at various temperatures (200°C to 600°C) for 1 h or at 400°C for different durations (1 h to 11 h) investigated by grazing-incidence x-ray diffraction (GIXRD) analysis, scanning electron microscopy (SEM), and four-point probe (FPP) measurements. Cu-1.8Al alloy thin film exhibited good thermal stability and low electrical resistivity (˜5.0 μΩ cm) after annealing at 500°C for 1 h or 400°C for 7 h. No copper silicide was observed at the Cu-Al/Si interface by GIXRD analysis or SEM for this sample. This result indicates that doping Cu thin film with small amounts of Al can achieve high thermal stability and low electrical resistivity, suggesting that Cu-1.8Al alloy thin film could be used for barrierless Cu metallization on Si substrate.

  2. The role of the microfissuration of the rock matrix in the abrasion resistance of ornamental granitic rocks

    Science.gov (United States)

    Rodríguez-Rey, Angel; Sanchez-Delgado, Nuria; Camino, Clara; Calleja, Lope; Ruiz de Argandoña, Vicente G.; Setien, Alexia

    2015-04-01

    The microcrack density and the abrasion resistance of five ornamental granites (Albero, Gris Alba, Mondariz, Rosa Porriño and Traspieles) from Galicia (NW Spain) have been quantified as part of a research aimed to interpret the cuttability of the rocks in relation to the petrophysical properties of the rock matrix. Large blocks from the quarries have been cut with an industrial saw and the microcrack density and the abrasion resistance have been measured in two surfaces: H, parallel to the cut surface; T, perpendicular both to the cut surface and the cutting direction. Both planes are perpendicular to the rift plane, as it is known in quarry works. The microcrack density has been quantified following an stereological procedure applied to polished sections imaged under scanning electron microscopy. The magnification of the images allowed the study of microcracks as narrow as 2 microns in aperture. The density has been quantified in terms of length of microcrack traces per surface unit so possible anisotropies of the microcrack network could be detected. The obtained values are in the typical range for this type of rocks although the Traspieles granite shows a higher value due to its weathering degree (H: 5.11, T: 5.37 mm/mm2). The values measured in the two surfaces (H and T) are quite similar in four of the rocks; only the Albero granite shows a marked anisotropy (H: 2.76 T: 3.53 mm/mm2). The abrasion resistance of the rocks has been measured following the european standard EN 14157:2004 using the capon method. The rocks can be classified in two groups according to their abrasion resistance. Rosa Porriño, Gris Alba and Mondariz granites are the more resistant to abrasion with values around 16-17 mm. Albero and Traspieles granites are less resistant with values higher than 19 mm. The results show a good correlation between the microcrack density and the abrasion resistance. As can be expected the rocks with high microcrack density show low abrasion resistance. The

  3. Structural and electrical properties of CuAlMo thin films prepared by magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Birkett, Martin, E-mail: martin.birkett@northumbria.ac.uk; Penlington, Roger; Wan, Chaoying; Zoppi, Guillaume

    2013-07-01

    The structural and electrical properties of a low resistivity CuAlMo thin film resistor material were investigated. The thin films were grown on Al{sub 2}O{sub 3} and glass substrates by direct current (dc) magnetron sputtering. The key electrical properties of sheet resistance, temperature coefficient of resistance (TCR) and resistance stability were investigated as a function of sputtering pressure and post-deposition heat treatment time and temperature. A low sputtering pressure range of 0.13 to 0.40 Pa produced CuAlMo films with sheet resistance in the range 0.1 to 0.2 Ω/□ and resistance stability of 0.45 to 0.65% with a TCR of − 90 ppm/°C which could be shifted to zero following annealing in air at 425 °C. Films grown at higher sputtering pressures of 0.53 to 0.80 Pa had increased sheet resistance in the range 0.4 to 0.6 Ω/□ and inferior stability of 0.8 to 1.7% with a more negative TCR of − 110 to − 180 ppm/°C which could not be shifted to zero following annealing. The stability of the films grown at 0.13 and 0.40 Pa could be further improved to < 0.25% with heat treatment, due to the formation of a protective aluminium oxide layer. A minimum dwell time of 3 h at 425 °C was required to stabilise the films and set the electrical properties. - Highlights: • Thin films of copper–aluminium–molybdenum were sputtered on alumina substrates. • Film properties were investigated with variation in process conditions. • Low sputtering pressure gave improved electrical performance. • Post deposition annealing in air further improved electrical performance.

  4. Structural and electrical properties of CuAlMo thin films prepared by magnetron sputtering

    International Nuclear Information System (INIS)

    Birkett, Martin; Penlington, Roger; Wan, Chaoying; Zoppi, Guillaume

    2013-01-01

    The structural and electrical properties of a low resistivity CuAlMo thin film resistor material were investigated. The thin films were grown on Al 2 O 3 and glass substrates by direct current (dc) magnetron sputtering. The key electrical properties of sheet resistance, temperature coefficient of resistance (TCR) and resistance stability were investigated as a function of sputtering pressure and post-deposition heat treatment time and temperature. A low sputtering pressure range of 0.13 to 0.40 Pa produced CuAlMo films with sheet resistance in the range 0.1 to 0.2 Ω/□ and resistance stability of 0.45 to 0.65% with a TCR of − 90 ppm/°C which could be shifted to zero following annealing in air at 425 °C. Films grown at higher sputtering pressures of 0.53 to 0.80 Pa had increased sheet resistance in the range 0.4 to 0.6 Ω/□ and inferior stability of 0.8 to 1.7% with a more negative TCR of − 110 to − 180 ppm/°C which could not be shifted to zero following annealing. The stability of the films grown at 0.13 and 0.40 Pa could be further improved to < 0.25% with heat treatment, due to the formation of a protective aluminium oxide layer. A minimum dwell time of 3 h at 425 °C was required to stabilise the films and set the electrical properties. - Highlights: • Thin films of copper–aluminium–molybdenum were sputtered on alumina substrates. • Film properties were investigated with variation in process conditions. • Low sputtering pressure gave improved electrical performance. • Post deposition annealing in air further improved electrical performance

  5. Optical and electrical properties of TiOPc doped Alq{sub 3} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Ramar, M.; Suman, C. K., E-mail: sumanck@nplindia.org; Tyagi, Priyanka; Srivastava, R. [CSIR-Network of Institutes for Solar Energy CSIR - National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi -110012 (India)

    2015-06-24

    The Titanyl phthalocyanine (TiOPc) was doped in Tris (8-hydroxyquinolinato) aluminum (Alq3) with different concentration. The thin film of optimized doping concentration was studied extensively for optical and electrical properties. The optical properties, studied using ellipsometry, absorption and photoluminescence. The absorption peak of Alq{sub 3} and TiOPc was observed at 387 nm and 707 nm and the photo-luminescence intensity (PL) peak of doped thin film was observed at 517 nm. The DC and AC electrical properties of the thin film were studied by current density-voltage (J-V) characteristics and impedance over a frequency range of 100 Hz - 1 MHz. The electron mobility calculated from trap-free space-charge limited region (SCLC) is 0.17×10{sup −5} cm{sup 2}/Vs. The Cole-Cole plots shows that the TiOPc doped Alq{sub 3} thin film can be represented by a single parallel resistance R{sub P} and capacitance C{sub P} network with a series resistance R{sub S} (10 Ω). The value of R{sub P} and C{sub P} at zero bias was 1587 Ω and 2.568 nF respectively. The resistance R{sub P} decreases with applied bias whereas the capacitance C{sub P} remains almost constant.

  6. Conducting atomic force microscopy studies on doped CulnO2 thin films for resistive memory device applications

    International Nuclear Information System (INIS)

    Mehta, B.R.

    2009-01-01

    Full text: Delafosite thin films have interesting structural, optical and electronic properties due to the highly anisotropic crystal structure and possibility of bipolar conductivity. In this presentation, optical, structural and electrical properties of Sn (n type) and Ca (p type) doped CulnO 2 layers grown by rf magnetron sputtering technique will be discussed. Depending on doping and deposition temperature, these films show nanocolumnar structure with (110) and (006) preferred orientations. The observed decrease in activation energy from 0.9 eV to about 0.10 eV and a large decrease in conductivity from 2.11 x 10 -10 Scm -1 to 1.66 x 10 -1 Scm -1 on Sn doping has been explained due to the change in preferred orientation along with efficient doping. Our results show that crystallite orientation is the most important factor controlling the electrical conduction in delafossite thin films. The anisotropy of electrical conduction along (006) and (110) directions in tin doped samples has been further established using conducting atomic force microscopy (CAFM) measurements. The CAFM measurements shows the presence of nanoconducting region when the current flow direction is aligned along the BO 6 layer and complete absence of conducting regions when the current direction is perpendicular to the film surface. Resistive memory devices based on Sn and Ca doped CulnO 2 films show stable and reproducible 'on' and 'off' states. CAFM measurement on these devices carried out before and after 'forming' show the growth of nanoconducting filaments on the application of a threshold voltage. It is possible to control resistance in the 'on' and 'off' states and magnitude of the forming and switching voltages by controlling the doping concentration and crystallite orientation in CulnO 2 layers

  7. Synthesis and characterization of Fe doped cadmium selenide thin films by spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Abhijit A., E-mail: aay_physics@yahoo.co.in [Thin Film Physics Laboratory, Department of Physics, Electronics and Photonics, Rajarshi Shahu Mahavidyalaya, Latur 413 512, Maharashtra (India)

    2012-12-05

    Highlights: Black-Right-Pointing-Pointer Simple and inexpensive method to dope trivalent Fe in CdSe thin films. Black-Right-Pointing-Pointer Fe doped CdSe thin films are highly photosensitive. Black-Right-Pointing-Pointer AFM analysis shows uniform deposition of film over the entire substrate surface. Black-Right-Pointing-Pointer The band gap energy decreases from 1.74 to 1.65 eV with Fe doping. Black-Right-Pointing-Pointer Film resistivity decreases to 6.76 Multiplication-Sign 10{sup 4} {Omega}-cm with Fe doping in CdSe thin films. - Abstract: Undoped and Fe doped CdSe thin films have been deposited onto the amorphous and fluorine doped tin oxide coated glass substrates by spray pyrolysis. The Fe doping concentration has been optimized by photoelectrochemical (PEC) characterization technique. The structural, surface morphological, compositional, optical and electrical properties of undoped and Fe doped CdSe thin films have been studied. X-ray diffraction study reveals that the as deposited CdSe films possess hexagonal crystal structure with preferential orientation along (1 0 0) plane. AFM analysis shows uniform deposition of the film over the entire substrate surface with minimum surface roughness of 7.90 nm. Direct allowed type of transition with band gap decreasing from 1.74 to 1.65 eV with Fe doping has been observed. The activation energy of the films has been found to be in the range of 0.14-0.19 eV at low temperature and 0.27-0.44 eV at high temperature. Semi-conducting behavior has been observed from resistivity measurements. The thermoelectric power measurements reveal that the films are of n type.

  8. SnS thin films deposited by chemical bath deposition, dip coating and SILAR techniques

    Science.gov (United States)

    Chaki, Sunil H.; Chaudhary, Mahesh D.; Deshpande, M. P.

    2016-05-01

    The SnS thin films were synthesized by chemical bath deposition (CBD), dip coating and successive ionic layer adsorption and reaction (SILAR) techniques. In them, the CBD thin films were deposited at two temperatures: ambient and 70 °C. The energy dispersive analysis of X-rays (EDAX), X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and optical spectroscopy techniques were used to characterize the thin films. The electrical transport properties studies on the as-deposited thin films were done by measuring the I-V characteristics, DC electrical resistivity variation with temperature and the room temperature Hall effect. The obtained results are deliberated in this paper.

  9. Optical and electrical properties of transparent conductive ITO thin films under proton radiation with 100 keV

    International Nuclear Information System (INIS)

    Wei, Q.; He, S.Y.; Yang, D.Z.; Liu, J.C.

    2005-01-01

    Under the simulation environment for the vacuum and heat sink in space, the changes in optical and electrical properties of transparent conductive indium tin oxide (ITO) thin films induced by radiation of protons with 100 keV were studied. The ITO thin films were deposited on JGS1 quartz substrate by a sol-gel method. The sheet resistance and transmittance spectra of the ITO thin films were measured using the four-point probe method and a spectrophotometer, respectively. The surface morphology was analyzed by AFM. The experimental results showed that the electrical and optical performances of the ITO thin films were closely related to the irradiation fluence. When the fluence exceeded a given value 2 x 10 16 cm -2 , the sheet resistance increased obviously and the optical transmittance decreased. The AFM analysis indicated that the grain size of the ITO thin films diminished. The studies about the radiation effect on ITO thin films will help to predict performance evolution of the second surface mirrors on satellites under space radiation environment. (orig.)

  10. Effects of Running Shoes with Abrasion Resistant Rubber Sole on the Exercise Capacity of the Human Body

    Directory of Open Access Journals (Sweden)

    Bo Wang

    2017-10-01

    Full Text Available With the development of industrialization, rubber has been gradually used in the manufacture of sports equipment for its favourable properties. This study involved the addition of C5 petroleum resin into brominated isobutylene-isoprene rubber (BIIR and butadiene rubber (BR while manufacturing the sole of running shoes. The effects of running shoes with abrasion resistant rubber sole on the exercise capacity of the human body were investigated by analysing the skid resistance and abrasion resistance of the running shoes, and conducting biomechanical study on naked feet and feet wearing the shoes. The results demonstrated that the rubber sole had favourable slip resistance property and mechanical properties such as stretching, abrasion resistance, and hardness. Compared to naked feet, the peak pressure intensity of the whole step of feet wearing the newly developed shoes, was significantly lower than that of feet wearing ordinary shoes. In the future, rubber can bring more comfortable experience because of its favourable properties.

  11. An investigation into which factors control the nanotribological behaviour of thin sputtered carbon films

    International Nuclear Information System (INIS)

    Shi Baogui; Sullivan, John L; Beake, Ben D

    2008-01-01

    Ultra-thin (20-100 nm) films deposited on Si surfaces can improve their mechanical and tribological properties. As a stepping stone towards the optimization of such ultra-thin films, herein we report experimental nanoscratch and nanowear data on a-C films of thickness in the range 200-1000 nm on Si aiming to (1) understand the role of film thickness on the nanoscratch behaviour, (2) determine whether the same factors (substrate bias, H/E ratio, etc) are at play for thick films as for the thin films, (3) determine possible design rules for thinner films enabling their optimization for MEMS applications and (4) evaluate the use of the multi-pass (3-scan) procedure for clarifying the locus of failure. To a first approximation, the critical load for total film failure in the nanoscratch test is proportional to thickness provided the films are not too stressed. a-C films of 1 μm with very high H/E, deposited under high substrate bias, perform well at low load but very poorly in more highly loaded situations. Not only do they exhibit low critical loads but also failure involves extensive delamination outside of the scratch track. This is not observed on thinner films. A suitable strategy for optimizing wear resistance for thin films for MEMS applications is to aim to maximize H/E. For the 200 nm films studied here, the films with the highest H/E showed slightly improved scratch resistance

  12. Phonon impedance matching: minimizing interfacial thermal resistance of thin films

    Science.gov (United States)

    Polanco, Carlos; Zhang, Jingjie; Ghosh, Avik

    2014-03-01

    The challenge to minimize interfacial thermal resistance is to allow a broad band spectrum of phonons, with non-linear dispersion and well defined translational and rotational symmetries, to cross the interface. We explain how to minimize this resistance using a frequency dependent broadening matrix that generalizes the notion of acoustic impedance to the whole phonon spectrum including symmetries. We show how to ``match'' two given materials by joining them with a single atomic layer, with a multilayer material and with a graded superlattice. Atomic layer ``matching'' requires a layer with a mass close to the arithmetic mean (or spring constant close to the harmonic mean) to favor high frequency phonon transmission. For multilayer ``matching,'' we want a material with a broadening close to the geometric mean to maximize transmission peaks. For graded superlattices, a continuous sequence of geometric means translates to an exponentially varying broadening that generates a wide-band antireflection coating for both the coherent and incoherent limits. Our results are supported by ``first principles'' calculations of thermal conductance for GaAs / Gax Al1 - x As / AlAs thin films using the Non-Equilibrium Greens Function formalism coupled with Density Functional Perturbation Theory. NSF-CAREER (QMHP 1028883), NSF-IDR (CBET 1134311), XSEDE.

  13. Electrical resistivity due to electron-phonon scattering in thin gadolinium films

    International Nuclear Information System (INIS)

    Urbaniak-Kucharczyk, A.

    1988-01-01

    The contribution to the electrical resistivity due to the electron-phonon scattering for the special case of h.c.p. structure is derived. The numerical results obtained for the case of polycrystalline gadolinum films show the resistivity dependence on the film thickness and the surface properties. (author)

  14. Electrical Switching of Perovskite Thin-Film Resistors

    Science.gov (United States)

    Liu, Shangqing; Wu, Juan; Ignatiev, Alex

    2010-01-01

    Electronic devices that exploit electrical switching of physical properties of thin films of perovskite materials (especially colossal magnetoresistive materials) have been invented. Unlike some related prior devices, these devices function at room temperature and do not depend on externally applied magnetic fields. Devices of this type can be designed to function as sensors (exhibiting varying electrical resistance in response to varying temperature, magnetic field, electric field, and/or mechanical pressure) and as elements of electronic memories. The underlying principle is that the application of one or more short electrical pulse(s) can induce a reversible, irreversible, or partly reversible change in the electrical, thermal, mechanical, and magnetic properties of a thin perovskite film. The energy in the pulse must be large enough to induce the desired change but not so large as to destroy the film. Depending on the requirements of a specific application, the pulse(s) can have any of a large variety of waveforms (e.g., square, triangular, or sine) and be of positive, negative, or alternating polarity. In some applications, it could be necessary to use multiple pulses to induce successive incremental physical changes. In one class of applications, electrical pulses of suitable shapes, sizes, and polarities are applied to vary the detection sensitivities of sensors. Another class of applications arises in electronic circuits in which certain resistance values are required to be variable: Incorporating the affected resistors into devices of the present type makes it possible to control their resistances electrically over wide ranges, and the lifetimes of electrically variable resistors exceed those of conventional mechanically variable resistors. Another and potentially the most important class of applications is that of resistance-based nonvolatile-memory devices, such as a resistance random access memory (RRAM) described in the immediately following article

  15. Effect of anisotropy on anomalous Hall effect in Tb-Fe thin films

    International Nuclear Information System (INIS)

    Babu, V. Hari; Markandeyulu, G.; Subrahmanyam, A.

    2009-01-01

    The electrical and Hall resistivities of Tb x Fe 100-x thin films in the temperature range 13-300 K were investigated. The sign of Hall resistivity at 300 K is found to change from positive for x=28 film to negative for x=30 film, in accordance with the compensation of Tb and Fe moments. All the films are seen to have planar magnetic anisotropy at 13 K. The temperature coefficients of electrical resistivities of the amorphous films with 19≤x≤51 are seen to be negative. The temperature dependence of Hall resistivity of these films is explained on the basis of random magnetic anisotropy model. The temperature dependences of Hall resistivities of the x=22 and 41 films are seen to exhibit a nonmonotonous behavior due to change in anisotropy from perpendicular to planar. The same behavior is considered for the explanation regarding the probable formation of Berry phase curvature in these films.

  16. Scaling behavior of mixed-state hall effect in MgB2 thin films

    International Nuclear Information System (INIS)

    Jung, Soon-Gil; Seong, W.K.; Kang, W.N.; Choi, Eun-Mi; Kim, Heon-Jung; Lee, Sung-Ik; Kim, Hyeong-Jin; Kim, H.C.

    2006-01-01

    The Hall resistivity (ρ xy ) and the longitudinal resistivity (ρ xx ) in c-axis-oriented superconducting MgB 2 thin films have been investigated in extended fields up to 18T. We have observed a scaling behavior between the Hall resistivity and the longitudinal resistivity, ρ xy =Aρ xx β , where the exponent (β) is observed to be independent of the temperatures and the magnetic fields. For a wide magnetic field region from 1 to 18T and a wide temperature region from 10 to 28K, a universal power law with β=2.0+/-0.1 was observed in c-axis-oriented MgB 2 thin films. These results can be well interpreted by using recent models

  17. Interfacial Properties of CZTS Thin Film Solar Cell

    Directory of Open Access Journals (Sweden)

    N. Muhunthan

    2014-01-01

    Full Text Available Cu-deficient CZTS (copper zinc tin sulfide thin films were grown on soda lime as well as molybdenum coated soda lime glass by reactive cosputtering. Polycrystalline CZTS film with kesterite structure was produced by annealing it at 500°C in Ar atmosphere. These films were characterized for compositional, structural, surface morphological, optical, and transport properties using energy dispersive X-ray analysis, glancing incidence X-ray diffraction, Raman spectroscopy, scanning electron microscopy, atomic force microscopy, UV-Vis spectroscopy, and Hall effect measurement. A CZTS solar cell device having conversion efficiency of ~0.11% has been made by depositing CdS, ZnO, ITO, and Al layers over the CZTS thin film deposited on Mo coated soda lime glass. The series resistance of the device was very high. The interfacial properties of device were characterized by cross-sectional SEM and cross-sectional HRTEM.

  18. Granularity effect on microwave surface resistance in high-Tc YBa2Cu3O7-x bulk and thin film superconductor

    International Nuclear Information System (INIS)

    Swarup, Ram; Gupta, A.K.

    2001-01-01

    We report the effect of variation of Josephson coupling strength in YBa 2 Cu 3 O 7-x (YBCO) superconductor due to grain enlargement, grain orientation and magnetic field on microwave surface resistance (R s ). The coupling strength in the bulk samples has been increased by increasing the sample density from 4.4 to 5.3 g/cm 3 , whereas in thin films, the same could be increased by increasing the c-axis orientation of the grains. The value of R s (10 GHz, 65 K) in bulk samples has been found to decrease from 52 to 4 mΩ with the increase of the coupling strength from 0.06 to 0.43 and in thin films from 930 to 600 μΩ with increase of the coupling strength from 0.92 to 2.43. The effect of grain decoupling on microwave surface resistance was studied under dc and microwave magnetic fields. The surface resistance increases gradually with the application of dc and microwave magnetic fields due to grain decoupling and finally gets saturated beyond a certain critical field. (author)

  19. Reversible Changes in Resistance of Perovskite Nickelate NdNiO3 Thin Films Induced by Fluorine Substitution.

    Science.gov (United States)

    Onozuka, Tomoya; Chikamatsu, Akira; Katayama, Tsukasa; Hirose, Yasushi; Harayama, Isao; Sekiba, Daiichiro; Ikenaga, Eiji; Minohara, Makoto; Kumigashira, Hiroshi; Hasegawa, Tetsuya

    2017-03-29

    Perovskite nickel oxides are of fundamental as well as technological interest because they show large resistance modulation associated with phase transition as a function of the temperature and chemical composition. Here, the effects of fluorine doping in perovskite nickelate NdNiO 3 epitaxial thin films are investigated through a low-temperature reaction with polyvinylidene fluoride as the fluorine source. The fluorine content in the fluorinated NdNiO 3-x F x films is controlled with precision by varying the reaction time. The fully fluorinated film (x ≈ 1) is highly insulating and has a bandgap of 2.1 eV, in contrast to NdNiO 3 , which exhibits metallic transport properties. Hard X-ray photoelectron and soft X-ray absorption spectroscopies reveal the suppression of the density of states at the Fermi level as well as the reduction of nickel ions (valence state changes from +3 to +2) after fluorination, suggesting that the strong Coulombic repulsion in the Ni 3d orbitals associated with the fluorine substitution drives the metal-to-insulator transition. In addition, the resistivity of the fluorinated films recovers to the original value for NdNiO 3 after annealing in an oxygen atmosphere. By application of the reversible fluorination process to transition-metal oxides, the search for resistance-switching materials could be accelerated.

  20. Process for obtaining multiple sheet resistances for thin film hybrid microcircuit resistors

    International Nuclear Information System (INIS)

    Norwood, D.P.

    1989-01-01

    A standard thin film circuit containing Ta/sub 2/N (100 ohms/square) resistors is fabricated by depositing on a dielectric substrate successive layers of Ta/sub 2/N, Ti and Pd, with a gold layer to provide conductors. The addition of a few simple photoprocessing steps to the standard TFN manufacturing process enables the formation of Ta/sub 2/N + Ti (10 ohms/square) and Ta/sub 2/N + Ti + Pd (1 ohm/square) resistors in the same otherwise standard thin film circuit structure

  1. DC magnetron sputtering prepared Ag-C thin film anode for thin film lithium ion microbatteries

    International Nuclear Information System (INIS)

    Li, Y.; Tu, J.P.; Shi, D.Q.; Huang, X.H.; Wu, H.M.; Yuan, Y.F.; Zhao, X.B.

    2007-01-01

    An Ag-C thin film was prepared by DC magnetron co-sputtering, using pure silver and graphite as the targets. The microstructure and morphology of the deposited thin film were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Electrochemical performances of the Ag-C thin film anode were investigated by means of discharge/charge and cyclic voltammogram (CV) tests in model cells. The electrochemical impedance spectrum (EIS) characteristics and the chemical diffusion coefficient, D Li of the Ag-C thin film electrode at different discharging states were discussed. It was believed that the excellent cycling performance of the Ag-C electrode was ascribed to the good conductivity of silver and the volume stability of the thin film

  2. Studies on transient characteristics of unipolar resistive switching processes in TiO2 thin film grown by atomic layer deposition

    Science.gov (United States)

    Sahu, Vikas Kumar; Das, Amit K.; Ajimsha, R. S.; Misra, P.

    2018-05-01

    The transient characteristics of resistive switching processes have been investigated in TiO2 thin films grown by atomic layer deposition (ALD) to study the temporal evolution of the switching processes and measure the switching times. The reset and set switching times of unipolar Au/TiO2/Pt devices were found to be ~250 µs and 180 ns, respectively in the voltage windows of 0.5–0.9 V for reset and 1.9–4.8 V for set switching processes, obtained from quasi-static measurements. The reset switching time decreased exponentially with increasing amplitude of applied reset voltage pulse, while the set switching time remained insensitive to the amplitude of the set voltage pulse. A fast reset process with a switching time of ~400 ns was achieved by applying a reset voltage of ~1.8 V, higher than that of the quasi-static reset voltage window but below the set voltage window. The sluggish reset process in TiO2 thin film and the dependence of the reset switching time on the amplitude of the applied voltage pulse was understood on the basis of a self-accelerated thermal dissolution model of conducting filaments (CFs), where a higher temperature of the CFs owing to enhanced Joule heating at a higher applied voltage imposes faster diffusion of oxygen vacancies, resulting in a shorter reset switching time. Our results clearly indicate that fast resistive switching with switching times in hundreds of nanoseconds can be achieved in ALD-grown TiO2 thin films. This may find applications in fast non-volatile unipolar resistive switching memories.

  3. Corrosion resistance of ZrNxOy thin films obtained by rf reactive magnetron sputtering

    International Nuclear Information System (INIS)

    Ariza, E.; Rocha, L.A.; Vaz, F.; Cunha, L.; Ferreira, S.C.; Carvalho, P.; Rebouta, L.; Alves, E.; Goudeau, Ph.; Riviere, J.P.

    2004-01-01

    The main aim of this work is the investigation of the corrosion resistance of single layered zirconium oxynitride, ZrN x O y , thin films in artificial sweat solution at ambient temperature. The films were produced by rf reactive magnetron sputtering, using a pure Zr target at a constant temperature of 300 deg. C. Two different sets of samples were produced. In the first set of films, the substrate bias voltage was the main variable, whereas in the second set, the flow rate of reactive gases (oxygen/nitrogen ratio) was varied. The control of the amount of oxygen allowed the film properties to be tailored from those of covalent zirconium nitride to those of the correspondent ionic oxide. The corrosion behaviour was evaluated by potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS) tests. The analysis of EIS data provided detailed information of the corrosion processes occurring at the surface of the system throughout the immersion time. The modifications of the coating microstructure and/or chemical composition induced by the variation of the deposition parameters were also evaluated and correlated with the corrosion mechanisms occurring in each system

  4. Investigation of the resistive transition of MgB2 thin film through current noise

    International Nuclear Information System (INIS)

    Gandini, C; Rajteri, M; Portesi, C; Monticone, E; Masoero, A; Mazzetti, P

    2006-01-01

    In this paper we present measurements concerning the current noise produced during the resistive transition in a MgB 2 polycrystalline thin film. The power spectrum of the current noise, observed when the temperature is slowly changed across its critical value, presents a large electrical noise of the 1/f n type (n ≅ 3) over a quite wide range of frequencies. This noise may be considered as generated by the abrupt creation of resistive strips across the specimen constituted by grains which have undergone the resistive transition. A computer model that takes into account fluctations of the grain critical currents and of the number of grain per strips, has been developed to simulate the resistive transition and to evaluate the noise power spectrum. When the temperature is incresed and reaches its critical value, resistive strips are formed according to a percolative process, giving rise to resistance steps which are at the origin of the noise. The theoretical results obtained by this model are in good agreement, concerning both the shape and intensity of the noise power spectrum, with the experimental data directly measured on the specimen

  5. Studies of tantalum nitride thin film resistors

    International Nuclear Information System (INIS)

    Langley, R.A.

    1975-01-01

    Backscattering of 2-MeV He ions was used to correlate the electrical properties of sputtered TaN/sub x/ thin-film resistors with their N content. The properties measured were sheet resistance, differential Seebeck potential (DSP), thermal coefficient of resistance (TCR), and stability. Resistivity and DSP are linearly dependent on N content for N/Ta ratios of 0.25 to 0.55. TCR decreases sharply below N/Ta = 0.35 and is relatively constant from 0.35 to 0.55. Stability is independent of N content. (DLC)

  6. Moderate temperature-dependent surface and volume resistivity and low-frequency dielectric constant measurements of pure and multi-walled carbon nanotube (MWCNT) doped polyvinyl alcohol thin films

    Science.gov (United States)

    Edwards, Matthew; Guggilla, Padmaja; Reedy, Angela; Ijaz, Quratulann; Janen, Afef; Uba, Samuel; Curley, Michael

    2017-08-01

    Previously, we have reported measurements of temperature-dependent surface resistivity of pure and multi-walled carbon nanotube (MWNCT) doped amorphous Polyvinyl Alcohol (PVA) thin films. In the temperature range from 22 °C to 40 °C with humidity-controlled environment, we found the surface resistivity to decrease initially, but to rise steadily as the temperature continued to increase. Moreover, electric surface current density (Js) was measured on the surface of pure and MWCNT doped PVA thin films. In this regard, the surface current density and electric field relationship follow Ohm's law at low electric fields. Unlike Ohmic conduction in metals where free electrons exist, selected captive electrons are freed or provided from impurities and dopants to become conduction electrons from increased thermal vibration of constituent atoms in amorphous thin films. Additionally, a mechanism exists that seemingly decreases the surface resistivity at higher temperatures, suggesting a blocking effect for conducting electrons. Volume resistivity measurements also follow Ohm's law at low voltages (low electric fields), and they continue to decrease as temperatures increase in this temperature range, differing from surface resistivity behavior. Moreover, we report measurements of dielectric constant and dielectric loss as a function of temperature and frequency. Both the dielectric constant and dielectric loss were observed to be highest for MWCNT doped PVA compared to pure PVA and commercial paper, and with frequency and temperature for all samples.

  7. Preparation and characterization of sprayed FTO thin films

    Science.gov (United States)

    Abd-Lefdil, M.; Diaz, R.; Bihri, H.; Aouaj, M. Ait; Rueda, F.

    2007-06-01

    Fluorine doped tin oxide (FTO) thin films have been prepared by spray pyrolysis technique with no further annealing. Films with 2.5% of fluorine grown at 400 °C present a single phase and exhibit a tetragonal structure with lattice parameters a = 4.687 Å and c = 3.160 Å. Scanning electron micrographs showed homogeneous surfaces with average grain size around 190 nm. The films are transparent in the visible zone and exhibit a high reflectance in the near infrared region. The best electrical resistivity was 6.3 × 10-4 Ω cm for FTO with 2.5% of fluorine. The ratio of transmittance in the visible to the sheet resistance are in the 0.57 × 10-2 1.96 × 10-2 {Ω }-1 range.

  8. Humidity Sensor Based on Multi-Walled Carbon Nanotube Thin Films

    International Nuclear Information System (INIS)

    Cao, C.L.; Hu, C.G.; Fang, L.; Wang, S.X.; Cao, C.L.; Tian, Y.S.; Pan, C.Y.

    2009-01-01

    The properties of the humidity sensors made of chemically treated and untreated multi-walled carbon nano tube (MWCNT) thin films are investigated systematically. It shows that both the chemically treated and untreated MWCNT thin films demonstrate humidity sensitive properties, but the former have stronger sensitivity than the latter. In the range of 11%-98% relative humidity (RH), the resistances of the chemically treated and untreated MWCNT humidity sensors increase 120% and 28%, respectively. Moreover, the treated humidity sensors showed higher sensitivity and better stability. In addition, the response and recover properties, and stabilization of the humidity sensors are measured, and the humidity sensitive mechanisms of the sensors are analyzed. The humidity sensitivity of carbon nano tube thin films indicates it promise as a kind of humidity sensitive material

  9. Soft Magnetic Properties of High-Entropy Fe-Co-Ni-Cr-Al-Si Thin Films

    Directory of Open Access Journals (Sweden)

    Pei-Chung Lin

    2016-08-01

    Full Text Available Soft magnetic properties of Fe-Co-Ni-Al-Cr-Si thin films were studied. As-deposited Fe-Co-Ni-Al-Cr-Si nano-grained thin films showing no magnetic anisotropy were subjected to field-annealing at different temperatures to induce magnetic anisotropy. Optimized magnetic and electrical properties of Fe-Co-Ni-Al-Cr-Si films annealed at 200 °C are saturation magnetization 9.13 × 105 A/m, coercivity 79.6 A/m, out-of-plane uniaxial anisotropy field 1.59 × 103 A/m, and electrical resistivity 3.75 μΩ·m. Based on these excellent properties, we employed such films to fabricate magnetic thin film inductor. The performance of the high entropy alloy thin film inductors is superior to that of air core inductor.

  10. Thin film metal-oxides

    CERN Document Server

    Ramanathan, Shriram

    2009-01-01

    Presents an account of the fundamental structure-property relations in oxide thin films. This title discusses the functional properties of thin film oxides in the context of applications in the electronics and renewable energy technologies.

  11. In-Plane Impedance Spectroscopy measurements in Vanadium Dioxide thin films

    Science.gov (United States)

    Ramirez, Juan; Patino, Edgar; Schmidt, Rainer; Sharoni, Amos; Gomez, Maria; Schuller, Ivan

    2012-02-01

    In plane Impedance Spectroscopy measurements have been done in Vanadium Dioxide thin films in the range of 100 Hz to 1 MHz. Our measurements allows distinguishing between the resistive and capacitive response of the Vanadium Dioxide films across the metal-insulator transition. A non ideal RC behavior was found in our thin films from room temperature up to 334 K. Around the MIT, an increase of the total capacitance is observed. A capacitor-network model is able to reproduce the capacitance changes across the MIT. Above the MIT, the system behaves like a metal as expected, and a modified equivalent circuit is necessary to describe the impedance data adequately.

  12. Thin films and nanomaterials

    International Nuclear Information System (INIS)

    Jayakumar, S.; Kannan, M.D.; Prasanna, S.

    2012-01-01

    The objective of this book is to disseminate the most recent research in Thin Films, Nanomaterials, Corrosion and Metallurgy presented at the International Conference on Advanced Materials (ICAM 2011) held in PSG College of Technology, Coimbatore, India during 12-16 December 2011. The book is a compilation of 113 chapters written by active researchers providing information and critical insights into the recent advancements that have taken place. Important new applications are possible today in the fields of microelectronics, opto-electronics, metallurgy and energy by the application of thin films on solid surfaces. Recent progress in high vacuum technology and new materials has a remarkable effect in thin film quality and cost. This has led to the development of new single or multi-layered thin film devices with diverse applications in a multitude of production areas, such as optics, thermal barrier coatings and wear protections, enhancing service life of tools and to protect materials against thermal and atmospheric influence. On the other hand, thin film process techniques and research are strongly related to the basic research activities in nano technology, an increasingly important field with countless opportunities for applications due to the emergence of new properties at the nanoscale level. Materials and structures that are designed and fabricated at the nano scale level, offer the potential to produce new devices and processes that may enhance efficiencies and reduce costs in many areas, as photovoltaic systems, hydrogen storage, fuel cells and solar thermal systems. In the book, the contributed papers are classified under two sections i) thin films and ii) nanomaterials. The thin film section includes single or multi layer conducting, insulating or semiconducting films synthesized by a wide variety of physical or chemical techniques and characterized or analyzed for different applications. The nanomaterials section deals with novel or exciting materials

  13. Construction of sputtering system and preparation of high temperature superconducting thin films

    International Nuclear Information System (INIS)

    Kaynak, E.

    2000-01-01

    The preparation of high T c superconducting thin film is important both for the understanding of fundamental behaviours of these materials and for the investigations on the usefulness of technological applications. High quality thin films can be prepared by various kinds of techniques being used today. Among these, sputtering is the most preferred one. The primary aim of this work is the construction of a r. f. and c. magnetron sputtering system. For this goal, a magnetron sputtering system was designed and constructed having powers up to 500W (r.f.) and 1KW (d.c.) that enables to deposit thin films of various kinds of materials: metals, ceramics and magnetic materials. The temperature dependence of the electrical resistance of the films was investigated by using four-point probe method. The zero resistance and the transition with of the films were measured as 80-85 K, and 2-9 K, respectively. The A.C. susceptibility experiments were done by utilising the system that was designed and constructed. The applied field dependence of the real and imaginary components of the susceptibility that were measured between the 77-120 K temperature interval and at a fixed frequency was investigated

  14. Natively textured surface hydrogenated gallium-doped zinc oxide transparent conductive thin films with buffer layers for solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xin-liang, E-mail: cxlruzhou@163.com; Wang, Fei; Geng, Xin-hua; Huang, Qian; Zhao, Ying; Zhang, Xiao-dan

    2013-09-02

    Natively textured surface hydrogenated gallium-doped zinc oxide (HGZO) thin films have been deposited via magnetron sputtering on glass substrates. These natively textured HGZO thin films exhibit rough pyramid-like textured surface, high optical transmittances in the visible and near infrared region and excellent electrical properties. The experiment results indicate that tungsten-doped indium oxide (In{sub 2}O{sub 3}:W, IWO) buffer layers can effectively improve the surface roughness and enhance the light scattering ability of HGZO thin films. The root-mean-square roughness of HGZO, IWO (10 nm)/HGZO and IWO (30 nm)/HGZO thin films are 28, 44 and 47 nm, respectively. The haze values at the wavelength of 550 nm increase from 7.0% of HGZO thin film without buffer layer to 18.37% of IWO (10 nm)/HGZO thin film. The optimized IWO (10 nm)/HGZO exhibits a high optical transmittance of 82.18% in the visible and near infrared region (λ ∼ 400–1100 nm) and excellent electrical properties with a relatively low sheet resistance of 3.6 Ω/□ and the resistivity of 6.21 × 10{sup −4} Ωcm. - Highlights: • Textured hydrogenated gallium-doped zinc oxide (HGZO) films were developed. • Tungsten-doped indium oxide (IWO) buffer layers were applied for the HGZO films. • Light-scattering ability of the HGZO films can be improved through buffer layers. • Low sheet resistance and high haze were obtained for the IWO(10 nm)/HGZO film. • The IWO/HGZO films are promising transparent conductive layers for solar cells.

  15. BDS thin film damage competition

    Science.gov (United States)

    Stolz, Christopher J.; Thomas, Michael D.; Griffin, Andrew J.

    2008-10-01

    A laser damage competition was held at the 2008 Boulder Damage Symposium in order to determine the current status of thin film laser resistance within the private, academic, and government sectors. This damage competition allows a direct comparison of the current state-of-the-art of high laser resistance coatings since they are all tested using the same damage test setup and the same protocol. A normal incidence high reflector multilayer coating was selected at a wavelength of 1064 nm. The substrates were provided by the submitters. A double blind test assured sample and submitter anonymity so only a summary of the results are presented here. In addition to the laser resistance results, details of deposition processes, coating materials, and layer count will also be shared.

  16. Superconducting thin films of YBa2Cu3O7-x

    International Nuclear Information System (INIS)

    Hudner, J.

    1993-01-01

    Thin films of the high temperature superconductor YBa 2 Cu 3 O 7-x (YBCO) are of significance in fundamental studies of oxide superconductors and for prospected electronic applications based on superconductors operating at liquid nitrogen temperatures (T= 77 K). Synthesis of YBCO thin films is complex and a large part of this thesis has been devoted to the elaboration of various techniques in forming YBCO thin films. A general observation was that synthesis of YBCO films exhibiting high zero-resistivity temperatures temperatures (T c ) ≥ 88 K and elevated critical current densities (J c ) ≥ 10 6 A/cm 2 at 77 K was possible under widely different conditions of film growth. For the BaF 2 -based method, various substrate materials were investigated. Among perovskite related substrates with low losses in the high frequency regime, LaA10 3 was found to yield YBCO films exhibiting the highest quality electrical properties. A study of YBCO film interaction with sapphire substrates was performed. It was suggested that the YBCO film on sapphire consists of weakly coupled superconducting grains. Compositional effects of Y, BA and Cu for MOCVD-YBCO films were examined with respect to morphology, structure, resistivity, as susceptibility and J c (T). High T c :s and J c :s were observed for an anomalous large compositional range of Cu in off-compositional YBCO films. This was shown to be related to the formation of Cu-rich precipitates embedded within a c-Axis oriented stoichiometric YBCO film matrix. Thermal critical current behavior at zero field in thin films of YBCO fabricated by various methods has been studied by three techniques: transport measurements on patterned microbridges, dc magnetization hysteresis loops using the Bean model and non-linear ac susceptibility analysis. Absolute critical current values obtained form the two former techniques when measured on the same YBCO film were observed to differ about a factor of two. The feasibility of non-linear ac

  17. Nanomechanical characterization of multilayered thin film structures for digital micromirror devices

    International Nuclear Information System (INIS)

    Wei Guohua; Bhushan, Bharat; Joshua Jacobs, S.

    2004-01-01

    The digital micromirror device (DMD), used for digital projection displays, comprises a surface-micromachined array of up to 2.07 million aluminum micromirrors (14 μm square and 15 μm pitch), which switch forward and backward thousands of times per second using electrostatic attraction. The nanomechanical properties of the thin-film structures used are important to the performance of the DMD. In this paper, the nanomechanical characterization of the single and multilayered thin film structures, which are of interest in DMDs, is carried out. The hardness, Young's modulus and scratch resistance of TiN/Si, SiO 2 /Si, Al alloy/Si, TiN/Al alloy/Si and SiO 2 /TiN/Al alloy/Si thin-film structures were measured using nanoindentation and nanoscratch techniques, respectively. The residual (internal) stresses developed during the thin film growth were estimated by measuring the radius of curvature of the sample before and after deposition. To better understand the nanomechanical properties of these thin film materials, the surface and interface analysis of the samples were conducted using X-ray photoelectron spectroscopy. The nanomechanical properties of these materials are analyzed and the impact of these properties on micromirror performance is discussed

  18. Direct observation of contact and channel resistance in pentacene four-terminal thin-film transistor patterned by laser ablation method

    International Nuclear Information System (INIS)

    Yagi, Iwao; Tsukagoshi, Kazuhito; Aoyagi, Yoshinobu

    2004-01-01

    We established a dry-etching patterning process for the channel formation of pentacene thin-film transistor, and fabricated a four-terminal device equipped with a gate electrode. The four-terminal device enabled us to divide two-terminal source-drain resistance into two components of contact resistance and pentacene channel resistance. We obtained direct evidence of a gate-voltagedependent contact resistance change: the gate-induced charge significantly reduced the contact resistance and increased source-drain current. Furthermore, the temperature dependence of the device clearly indicated that the contact resistance was much higher than the channel resistance and was dominated in the two-terminal total resistance of the device below 120 K. An observed activation energy of 80 meV for contact resistance was higher than that of 42 meV for pentacene channel resistance

  19. Optoelectronic properties of R-F magnetron sputtered Cadmium Tin Oxide (Cd2SnO4) thin films for CdS/CdTe thin film solar cell applications

    International Nuclear Information System (INIS)

    Jeyadheepan, K.; Thamilselvan, M.; Kim, Kyunghae; Yi, Junsin; Sanjeeviraja, C.

    2015-01-01

    Highlights: • Characterization of “as-prepared” Cd 2 SnO 4 thin films ideal for thin film solar cells. • Lowest value of resistivity with high mobility attained for the as-prepared Cd 2 SnO 4 films. • Maximum transmittance of 93% in the visible range for the as-prepared films. • Effect of substrate temperature on the scattering mechanism of TCO. - Abstract: The influence of substrate temperature on the microstructural behavior, optical, electrical properties and on the scattering mechanism of charge carriers were studied for the as-prepared radio-frequency (R-F) magnetron sputtered Cadmium Tin Oxide (Cd 2 SnO 4 ) thin films. Films prepared at the substrate temperature of 300 °C were found to be polycrystalline in nature with preferential orientation along (3 1 1) plane. Well pronounced Moss–Burstein shift, in the transmittance spectra with dispersions in the optical band gap from 3.07 to 3.30 eV, was observed at substrate temperatures between 25 and 300 °C. Optical property of high visible transmittance was retained by the films. Analysis of the electrical properties on the prepared crystalline Cd 2 SnO 4 films showed a calculated resistivity of 10 −3 –10 −4 Ω cm, with n-type carrier density in the range of 10 19 –10 20 cm −3 and the charge carrier mobility in the range of 63–30 cm 2 /V s. The effects of structural, compositional and optical properties on the scattering mechanism of charge carrier are elaborated and reported to be an experimental evidence for the theoretical predictions. The results revealed the essential DC electrical conduction behavior, which is ideal for the fabrication of Cd 2 SnO 4 -based CdS/CdTe thin film solar cells

  20. Frequency dependence of the active impedance component of silicon thin-film resistors

    International Nuclear Information System (INIS)

    Belogurov, S.V.; Gostilo, V.V.; Yurov, A.S.

    1987-01-01

    A high-resistant resistor on the silicon thin-film substrate considerably superior in noise and frequency performance than commercial resistors is described. The frequency dependence of the active impedance component is tested for determining noise and frequency dependences of silicon thin-film resistors. The obtained results permit to calculate the energy equivalent of resistor noise in nuclear radiation detection units at any temperature according to its frequency characteristic at room temperature

  1. Investigation of the High Mobility IGZO Thin Films by Using Co-Sputtering Method

    Science.gov (United States)

    Hsu, Chao-Ming; Tzou, Wen-Cheng; Yang, Cheng-Fu; Liou, Yu-Jhen

    2015-01-01

    High transmittance ratio in visible range, low resistivity, and high mobility of IGZO thin films were prepared at room temperature for 30 min by co-sputtering of Zn2Ga2O5 (Ga2O3 + 2 ZnO, GZO) ceramic and In2O3 ceramic at the same time. The deposition power of pure In2O3 ceramic target was fixed at 100 W and the deposition power of GZO ceramic target was changed from 80 W to 140 W. We chose to investigate the deposition power of GZO ceramic target on the properties of IGZO thin films. From the SEM observations, all of the deposited IGZO thin films showed a very smooth and featureless surface. From the measurements of XRD patterns, only the amorphous structure was observed. We aimed to show that the deposition power of GZO ceramic target had large effect on the Eg values, Hall mobility, carrier concentration, and resistivity of IGZO thin films. Secondary ion mass spectrometry (SIMS) analysis in the thicknesses’ profile of IGZO thin films found that In and Ga elements were uniform distribution and Zn element were non-uniform distribution. The SIMS analysis results also showed the concentrations of Ga and Zn elements increased and the concentrations of In element was almost unchanged with increasing deposition power.

  2. Investigation of the High Mobility IGZO Thin Films by Using Co-Sputtering Method

    Directory of Open Access Journals (Sweden)

    Chao-Ming Hsu

    2015-05-01

    Full Text Available High transmittance ratio in visible range, low resistivity, and high mobility of IGZO thin films were prepared at room temperature for 30 min by co-sputtering of Zn2Ga2O5 (Ga2O3 + 2 ZnO, GZO ceramic and In2O3 ceramic at the same time. The deposition power of pure In2O3 ceramic target was fixed at 100 W and the deposition power of GZO ceramic target was changed from 80 W to 140 W. We chose to investigate the deposition power of GZO ceramic target on the properties of IGZO thin films. From the SEM observations, all of the deposited IGZO thin films showed a very smooth and featureless surface. From the measurements of XRD patterns, only the amorphous structure was observed. We aimed to show that the deposition power of GZO ceramic target had large effect on the Eg values, Hall mobility, carrier concentration, and resistivity of IGZO thin films. Secondary ion mass spectrometry (SIMS analysis in the thicknesses’ profile of IGZO thin films found that In and Ga elements were uniform distribution and Zn element were non-uniform distribution. The SIMS analysis results also showed the concentrations of Ga and Zn elements increased and the concentrations of In element was almost unchanged with increasing deposition power.

  3. Effect on the properties of ITO thin films in Gamma environment

    Science.gov (United States)

    Sofi, A. H.; Shah, M. A.; Asokan, K.

    2018-04-01

    The present study reports the effect of gamma irradiation of varying doses (0-200 kGy) on the physical properties of the indium tin oxide (ITO) thin films. The films were fabricated by thermal evaporation method using indium-tin (InSn) ingots followed by an oxidation in atmosphere at a temperature of 550 °C. X-ray diffraction analysis confirmed the body-centered cubic (BCC) structure corresponds to the ITO thin films, high phase purity and a variation in crystallite size between 30-44 nm. While the optical studies revealed an increase in transmission as well as variation in optical band gap, the electrical studies confirmed n-type semiconductive behavior of the thin films, increase in mobility and a decrease in resistivity from 2.33×10-2 - 9.31×10-4 Ωcm with the increase in gamma dose from 0-200 kGy. The gamma irradiation caused totally electronic excitation and resulted in this modifications. The degenerate electron gas model was considered when attempting to understand the prevalent scattering mechanism in gamma irradiated ITO thin films.

  4. Dependence on film thickness of grain boundary low-field magnetoresistance in thin films of La0.7Ca0.3MnO3

    International Nuclear Information System (INIS)

    Todd, N. K.; Mathur, N. D.; Blamire, M. G.

    2001-01-01

    The magnetoresistance of grain boundaries in the perovskite manganites is being studied, both in polycrystalline materials, and thin films grown on bicrystal substrates, because of interest in low-field applications. In this article we show that epitaxial films grown on SrTiO 3 bicrystal substrates of 45 degree misorientation show magnetoresistance behavior which is strongly dependent on the thickness of the film. Thin films, e.g., 40 nm, can show a large low-field magnetoresistance at low temperatures, with very sharp switching between distinct high and low resistance states for fields applied in plane and parallel to the boundary. Thicker films show a more complex behavior of resistance as a function of field, and the dependence on the angle between the applied field and the grain boundary is altered. These changes in magnetoresistance behavior are linked to the variation in morphology of the films. Thin films are coherently strained, due to the mismatch with the substrate, and very smooth. Thicker films relax, with the formation of defects, and hence different micromagnetic behavior. [copyright] 2001 American Institute of Physics

  5. Thin film Ag superlens towards lab-on-a-chip integration

    DEFF Research Database (Denmark)

    Jeppesen, Claus; Nielsen, Rasmus Bundgaard; Boltasseva, Alexandra

    2009-01-01

    A thin metal film near-field superlens, as originally suggested by Pendry and realized by Fang et al. and Melville et al., is investigated with emphasis on materials suitable for integration on a lab-on-a-chip platform. A chemically resistant cyclo-olefin copolymer (COC), mr-I-T85 from microresist...... technology, is applied as dielectric matrix/spacer for an Ag thin film superlens. The superlens successfully resolves 80 nm half-pitch gratings when illuminated with UV radiation at a free space wavelength of 365 nm. The superlens design, fabrication and characterization is discussed....

  6. Progress in thin film techniques

    International Nuclear Information System (INIS)

    Weingarten, W.

    1996-01-01

    Progress since the last Workshop is reported on superconducting accelerating RF cavities coated with thin films. The materials investigated are Nb, Nb 3 Sn, NbN and NbTiN, the techniques applied are diffusion from the vapour phase (Nb 3 Sn, NbN), the bronze process (Nb 3 Sn), and sputter deposition on a copper substrate (Nb, NbTiN). Specially designed cavities for sample evaluation by RF methods have been developed (triaxial cavity). New experimental techniques to assess the RF amplitude dependence of the surface resistance are presented (with emphasis on niobium films sputter deposited on copper). Evidence is increasing that they are caused by magnetic flux penetration into the surface layer. (R.P.)

  7. Abrasive wear resistance and microstructure of Ni-Cr-B-Si hardfacing alloys with additions of Al, Nb, Mo, Fe, Mn and C

    International Nuclear Information System (INIS)

    Berns, H.; Fischer, A.; Theisen, W.

    1987-01-01

    The development of new Ni-base hardfacing alloys for filler wire welding or metal spraying should result in materials with a good resistance against high temperature corrosion and abrasive wear. The first step is to design microstructures, which obtain a satisfactory abrasive wear behaviour at room temperature. Thus, different alloys are melted and scrutinized as to their microstructure and their abrasive wear resistance in laboratory. Compared to commercial Ni-base hardfacing alloys they show a higher volume fraction of coarse hard phases due to the additional, initial solidification of Nb-carbides and Cr-, and Mo-borides. Thus, the abrasive wear resistance is improved. For hard abrasive particles, such as corundum, the Ni-base alloys are more wear resistant than harder Fe-base alloys investigate earlier. This is due to the tougher Ni metal matrix that results in microcracking not to be the most significantly acting wear mechanism

  8. High rate deposition of transparent conducting oxide thin films by vacuum arc plasma evaporation

    International Nuclear Information System (INIS)

    Minami, Tadatsugu; Ida, Satoshi; Miyata, Toshihiro

    2002-01-01

    Transparent conducting oxide (TCO) thin films have been deposited at a high rate above 370 nm/min by vacuum arc plasma evaporation (VAPE) using sintered oxide fragments as the source material. It was found that the deposition rate of TCO films was strongly dependent on the deposition pressure, whereas the obtained electrical properties were relatively independent of the pressure. Resistivities of 5.6x10 -4 and 2.3x10 -4 Ω·cm and an average transmittance above 80% (with substrate included) in the visible range were obtained in Ga-doped ZnO (GZO) thin films deposited at 100 and 350 deg. C, respectively. In addition, a resistivity as low as 1.4x10 -4 Ω·cm and an average transmittance above 80% were also obtained in indium-tin-oxide (ITO) films deposited at 300 deg. C. The deposited TCO films exhibited uniform distributions of resistivity and thickness on large area substrates

  9. High rate deposition of transparent conducting oxide thin films by vacuum arc plasma evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Minami, Tadatsugu; Ida, Satoshi; Miyata, Toshihiro

    2002-09-02

    Transparent conducting oxide (TCO) thin films have been deposited at a high rate above 370 nm/min by vacuum arc plasma evaporation (VAPE) using sintered oxide fragments as the source material. It was found that the deposition rate of TCO films was strongly dependent on the deposition pressure, whereas the obtained electrical properties were relatively independent of the pressure. Resistivities of 5.6x10{sup -4} and 2.3x10{sup -4} {omega}{center_dot}cm and an average transmittance above 80% (with substrate included) in the visible range were obtained in Ga-doped ZnO (GZO) thin films deposited at 100 and 350 deg. C, respectively. In addition, a resistivity as low as 1.4x10{sup -4} {omega}{center_dot}cm and an average transmittance above 80% were also obtained in indium-tin-oxide (ITO) films deposited at 300 deg. C. The deposited TCO films exhibited uniform distributions of resistivity and thickness on large area substrates.

  10. Multiferroic oxide thin films and heterostructures

    KAUST Repository

    Lu, Chengliang

    2015-05-26

    Multiferroic materials promise a tantalizing perspective of novel applications in next-generation electronic, memory, and energy harvesting technologies, and at the same time they also represent a grand scientific challenge on understanding complex solid state systems with strong correlations between multiple degrees of freedom. In this review, we highlight the opportunities and obstacles in growing multiferroic thin films with chemical and structural integrity and integrating them in functional devices. Besides the magnetoelectric effect, multiferroics exhibit excellent resistant switching and photovoltaic properties, and there are plenty opportunities for them to integrate with other ferromagnetic and superconducting materials. The challenges include, but not limited, defect-related leakage in thin films, weak magnetism, and poor control on interface coupling. Although our focuses are Bi-based perovskites and rare earth manganites, the insights are also applicable to other multiferroic materials. We will also review some examples of multiferroic applications in spintronics, memory, and photovoltaic devices.

  11. Electrical Transport and Magnetoresistance Properties of Tensile-Strained CaMnO3 Thin Films

    Science.gov (United States)

    Ullery, Dustin; Lawson, Bridget; Zimmerman, William; Neubauer, Samuel; Chaudhry, Adeel; Hart, Cacie; Yong, Grace; Smolyaninova, Vera; Kolagani, Rajeswari

    We will present our studies of the electrical transport and magnetoresistance properties of tensile strained CaMnO3 thin films. We observe that the resistivity decreases significantly as the film thickness decreases which is opposite to what is observed in thin films of hole doped manganites. The decrease in resistivity is more pronounced in the films on (100) SrTiO3, with resistivity of the thinnest films being about 3 orders of magnitude lower than that of bulk CaMnO3. Structural changes accompanying resistivity changes cannot be fully explained as due to tensile strain, and indicate the presence of oxygen vacancies. These results also suggest a coupling between tensile strain and oxygen deficiency, consistent with predictions from models based on density functional theory calculations. We observe a change in resistance under the application of moderate magnetic field. Experiments are underway to understand the origin of the magnetoresistance and its possible relation to the tensile strain effects. We acknowledge support from: Towson Office of University Undergraduate Research, Fisher Endowment Grant and Undergraduate Research Grants from the Fisher College of Science and Mathematics, and Seed Funding Grant from the School of Emerging technologies.

  12. Strength and gas-abrasive wear-resistance of zirconium carbide based cerments

    International Nuclear Information System (INIS)

    Samsonov, G.V.; Dan'kin, A.A.; Markov, A.A.; Bogomol, I.V.

    1976-01-01

    Results relating to a study of cermet strength and wear resistance by means of a gas-abrasive flow are presented. It has been found that with a higher amount of the metallic binder (over 25 at.%) in zirconium carbide-based cermets the bending and compression strength and also hardness and wear resistance within the systems ZrC-Nb, ZrC-Mo, ZrC-W become lower. The interrelation of the cermet wear resistance of the various systems and their bending and compression strengths, which, in turn, depend on the electronic structure is shown

  13. The Effects of Strain on the Electrical Properties of Thin Evaporated Films of Semiconductor Compounds

    Science.gov (United States)

    Steel, G. G.

    1970-01-01

    Reports on project intended to establish how electrical resistance, Hall voltage, and magnetoresistance change when a thin film specimen is subjected to mechanical strain. Found resistance of semiconducting film of indium arsenide and indium antimonide decreases with tension and increases with compression. (LS)

  14. Property elucidation of vacuum-evaporated zinc telluride thin film ...

    Indian Academy of Sciences (India)

    J U Ahamed

    2017-08-31

    Aug 31, 2017 ... method for the deposition of ZnTe thin film as compared to other methods. ... the advantages and disadvantages of different deposition process, it was ... by a spiral resistance heater and the temperature was measured by a ...

  15. Investigation of cosputtered W--C thin films as diffusion barriers

    International Nuclear Information System (INIS)

    Yang, H.Y.; Zhao, X.

    1988-01-01

    Polycrystalline thin films of W--C were deposited on single-crystal Si or SiO 2 substrates by rf planar magnetron cosputtering of graphite (C) and W targets. The performance of cosputtered W 75 C 25 thin films as diffusion barriers between a Si substrate and metallic overlayers of Ag, Au, or Al was investigated. Backscattering spectrometry and x-ray diffraction are used to detect metallurgical interactions. Four-point probe measurement of resistance is employed to monitor the electrical stability of the metallization schemes upon thermal annealing in a vacuum for 30 min in temperature ranges from 500 to 700 0 C. The electrical resistivity of W 75 C 25 films is 140 μΩ cm. A W 75 C 25 layer 1100 A thick prevents metallurgical interdiffusion and reaction between Au or Ag overlayers and the Si substrates up to 700 0 C, and between an Al overlayer and the Si substrate up to 450 0 C.tential

  16. Experimental investigation on photoelectric properties of ZAO thin film deposited on flexible substrate by magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Ming [School of Mechanical Engineering and Automation, Northeastern University, 3-11 WenHua Rd., 319#, Shenyang, 110004 (China); Liu, Kun, E-mail: kliu@mail.neu.edu.cn [School of Mechanical Engineering and Automation, Northeastern University, 3-11 WenHua Rd., 319#, Shenyang, 110004 (China); Liu, Xinghua [Hubei Aerospace Industry Technology Academe Special Vehicle Technology Center, Wuhan (China); Wang, Dongyang; Ba, Dechun; Xie, Yuanhua; Du, Guangyu; Ba, Yaoshuai [School of Mechanical Engineering and Automation, Northeastern University, 3-11 WenHua Rd., 319#, Shenyang, 110004 (China)

    2016-12-01

    Highlights: • ZAO thin films were deposited on PET substrate. • A set of experimental parameters were systematically investigated. • Change rule of film photoelectric properties was obtained. • ZAO films with optimal properties were obtained at our working conditions. - Abstract: Transparent conductive ZAO (Zinc Aluminum Oxide) films on flexible substrates have a great potential for low-cost mass-production solar cells. ZAO thin films were achieved on flexible PET (polyethylene terephthalate) substrates by RF magnetron sputtering technology. The surface morphology and element content, the transmittance and the sheet resistance of the films were measured to determine the optical process parameters. The results show that the ZAO thin film shows the best parameters in terms of photoelectric performance including sputtering power, working pressure, sputtering time, substrate temperature (100 W, 1.5 Pa, 60 min, 125 °C). The sheet resistance of 510 Ω and transmittance in visible region of 92% were obtained after characterization. Surface morphology was uniform and compact with a good crystal grain.

  17. Experimental investigation on photoelectric properties of ZAO thin film deposited on flexible substrate by magnetron sputtering

    International Nuclear Information System (INIS)

    Hao, Ming; Liu, Kun; Liu, Xinghua; Wang, Dongyang; Ba, Dechun; Xie, Yuanhua; Du, Guangyu; Ba, Yaoshuai

    2016-01-01

    Highlights: • ZAO thin films were deposited on PET substrate. • A set of experimental parameters were systematically investigated. • Change rule of film photoelectric properties was obtained. • ZAO films with optimal properties were obtained at our working conditions. - Abstract: Transparent conductive ZAO (Zinc Aluminum Oxide) films on flexible substrates have a great potential for low-cost mass-production solar cells. ZAO thin films were achieved on flexible PET (polyethylene terephthalate) substrates by RF magnetron sputtering technology. The surface morphology and element content, the transmittance and the sheet resistance of the films were measured to determine the optical process parameters. The results show that the ZAO thin film shows the best parameters in terms of photoelectric performance including sputtering power, working pressure, sputtering time, substrate temperature (100 W, 1.5 Pa, 60 min, 125 °C). The sheet resistance of 510 Ω and transmittance in visible region of 92% were obtained after characterization. Surface morphology was uniform and compact with a good crystal grain.

  18. Pathways to Mesoporous Resin/Carbon Thin Films with Alternating Gyroid Morphology

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qi [Department; Matsuoka, Fumiaki [Department; Suh, Hyo Seon [Institute; Materials; Beaucage, Peter A. [Department; Xiong, Shisheng [Institute; Materials; Smilgies, Detlef-M. [Cornell; Tan, Kwan Wee [Department; School; Werner, Jörg G. [Department; Nealey, Paul F. [Institute; Materials; Wiesner, Ulrich B. [Department

    2017-12-19

    Three-dimensional (3D) mesoporous thin films with sub-100 nm periodic lattices are of increasing interest as templates for a number of nanotechnology applications, yet are hard to achieve with conventional top-down fabrication methods. Block copolymer self-assembly derived mesoscale structures provide a toolbox for such 3D template formation. In this work, single (alternating) gyroidal and double gyroidal mesoporous thin-film structures are achieved via solvent vapor annealing assisted co-assembly of poly(isoprene-block-styrene-block-ethylene oxide) (PI-b-PS-b-PEO, ISO) and resorcinol/phenol formaldehyde resols. In particular, the alternating gyroid thin-film morphology is highly desirable for potential template backfilling processes as a result of the large pore volume fraction. In situ grazing-incidence small-angle X-ray scattering during solvent annealing is employed as a tool to elucidate and navigate the pathway complexity of the structure formation processes. The resulting network structures are resistant to high temperatures provided an inert atmosphere. The thin films have tunable hydrophilicity from pyrolysis at different temperatures, while pore sizes can be tailored by varying ISO molar mass. A transfer technique between substrates is demonstrated for alternating gyroidal mesoporous thin films, circumventing the need to re-optimize film formation protocols for different substrates. Increased conductivity after pyrolysis at high temperatures demonstrates that these gyroidal mesoporous resin/carbon thin films have potential as functional 3D templates for a number of nanomaterials applications.

  19. Comparative study of the mechanical properties of nanostructured thin films on stretchable substrates

    Energy Technology Data Exchange (ETDEWEB)

    Djaziri, S. [Max-Planck-Institut für Eisenforschung GmbH, Max-Planck-Straße 1, 40237 Düsseldorf (Germany); Institut P' (UPR 3346 CNRS), Université de Poitiers, ENSMA, Bd Pierre et Marie Curie, 86962 Futuroscope Cedex (France); Renault, P.-O.; Le Bourhis, E.; Goudeau, Ph., E-mail: Philippe.goudeau@univ-poitiers.fr [Institut P' (UPR 3346 CNRS), Université de Poitiers, ENSMA, Bd Pierre et Marie Curie, 86962 Futuroscope Cedex (France); Faurie, D. [LSPM, (UPR 3407 CNRS), Université Paris 13, Institut Galilée, 99 avenue Jean-Baptiste Clément, 93430 Villetaneuse (France); Geandier, G. [Institut Jean Lamour (UMR 3079 CNRS), Université de Lorraine, Parc de Saurupt, CS 50840, 54011 NANCY Cedex (France); Mocuta, C.; Thiaudière, D. [Synchrotron SOLEIL, L' Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex (France)

    2014-09-07

    Comparative studies of the mechanical behavior between copper, tungsten, and W/Cu nanocomposite based on copper dispersoïd thin films were performed under in-situ controlled tensile equi-biaxial loadings using both synchrotron X-ray diffraction and digital image correlation techniques. The films first deform elastically with the lattice strain equal to the true strain given by digital image correlation measurements. The Cu single thin film intrinsic elastic limit of 0.27% is determined below the apparent elastic limit of W and W/Cu nanocomposite thin films, 0.30% and 0.49%, respectively. This difference is found to be driven by the existence of as-deposited residual stresses. Above the elastic limit on the lattice strain-true strain curves, we discriminate two different behaviors presumably footprints of plasticity and fracture. The Cu thin film shows a large transition domain (0.60% true strain range) to a plateau with a smooth evolution of the curve which is associated to peak broadening. In contrast, W and W/Cu nanocomposite thin films show a less smooth and reduced transition domain (0.30% true strain range) to a plateau with no peak broadening. These observations indicate that copper thin film shows some ductility while tungsten/copper nanocomposites thin films are brittle. Fracture resistance of W/Cu nanocomposite thin film is improved thanks to the high compressive residual stress and the elimination of the metastable β-W phase.

  20. Physical property improvement of IZTO thin films using a hafnia buffer layer

    Science.gov (United States)

    Park, Jong-Chan; Kang, Seong-Jun; Choi, Byeong-Gyun; Yoon, Yung-Sup

    2018-01-01

    Hafnia (HfO2) has excellent mechanical and chemical stability, good transmittance, high dielectric constant, and radiation resistance property; thus, it can prevent impurities from permeating into the depositing films. So, we deposited hafnia films with various thicknesses in the range of 0-60 nm on polyethylene naphthalate (PEN) substrates before depositing indium-zinc-tin oxide (IZTO) thin films on them using RF magnetron sputtering, and their structural, morphological, optical, and electrical properties were evaluated. All IZTO thin films were successfully deposited without cracks or pinholes and had amorphous structures. As the thickness of the hafnia film increased to 30 nm, the overall properties improved; a surface roughness of 2.216 nm, transmittance of 82.59% at 550 nm, resistivity of 5.66 × 10-4 Ω cm, sheet resistance of 23.60 Ω/sq, and figure of merit of 6.26 × 10-3 Ω-1 were realized. These results indicate that the structure and materials studied in this research are suitable for application in flexible transparent electronic devices such as organic light emitting diodes, liquid crystal displays, touch panels, and solar cells.

  1. Thickness characteristics of YBaCuO system thin films prepared by RF magnetron sputtering

    International Nuclear Information System (INIS)

    Furuhashi, Hideo; Jinno, Makoto; Takashima, Osamu; Uchida, Yoshiyuki; Maeda, Akinori; Kojima, Kenzo; Ochiai, Shizuyasu; Ohashi, Asao

    1994-01-01

    The practical use of oxide high temperature superconductors for electronics field has been advanced. The oxide high temperature superconductor thin films is very sensitive to the production conditions, and their making with good reproducibility is difficult. In this study, the method of producing the thin films having good quality with good reproducibility by RF magnetron sputtering, and the relation of the film thickness with the superconductivity characteristics of YBaCuO system thin films in the different methods of substrate washing were examined. The sputtering conditions are shown. For the purpose of preventing the worsening of the film quality due to the reverse sputtering of oxygen negative ions to the thin film surface, sputtering gas pressure was set up high at 30 Pa. The film thickness and the temperature-resistance characteristics were measured. The experimental method and the experimental results are reported. By keeping the temperature on substrate surfaces constant, the reproducibility in the production of the thin films was improved remarkably. The effect of substrate washing was large. (K.I.)

  2. Thin film device applications

    CERN Document Server

    Kaur, Inderjeet

    1983-01-01

    Two-dimensional materials created ab initio by the process of condensation of atoms, molecules, or ions, called thin films, have unique properties significantly different from the corresponding bulk materials as a result of their physical dimensions, geometry, nonequilibrium microstructure, and metallurgy. Further, these characteristic features of thin films can be drasti­ cally modified and tailored to obtain the desired and required physical characteristics. These features form the basis of development of a host of extraordinary active and passive thin film device applications in the last two decades. On the one extreme, these applications are in the submicron dimensions in such areas as very large scale integration (VLSI), Josephson junction quantum interference devices, magnetic bubbles, and integrated optics. On the other extreme, large-area thin films are being used as selective coatings for solar thermal conversion, solar cells for photovoltaic conver­ sion, and protection and passivating layers. Ind...

  3. Improved electrical conduction properties in unintentionally-doped ZnO thin films treated by rapid thermal annealing

    International Nuclear Information System (INIS)

    Lee, Youngmin; Lee, Choeun; Shim, Eunhee; Jung, Eiwhan; Lee, Jinyong; Kim, Deukyoung; Lee, Sejoon; Fu, Dejun; Yoon, Hyungdo

    2011-01-01

    The effects of thermal treatments on the electrical conduction properties for the unintentionally doped ZnO thin films were investigated. Despite the decreased carrier density in the annealed ZnO thin films, the conductivity was increased because the contribution of the effective carrier mobility to the conductivity of the unintentionally-doped ZnO thin films is greater than that of the carrier density. The resistivity exponentially decreased with increasing RTA temperature, and this result was confirmed to come from the enhanced effective carrier-mobility, which originated from the increased crystallite size in the annealed ZnO thin films.

  4. Improved electrical conduction properties in unintentionally-doped ZnO thin films treated by rapid thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youngmin; Lee, Choeun; Shim, Eunhee; Jung, Eiwhan; Lee, Jinyong; Kim, Deukyoung; Lee, Sejoon [Dongguk University-Seoul, Seoul (Korea, Republic of); Fu, Dejun [Wuhan University, Wuhan (China); Yoon, Hyungdo [Korea Electronics Technology Institute, Seongnam (Korea, Republic of)

    2011-10-15

    The effects of thermal treatments on the electrical conduction properties for the unintentionally doped ZnO thin films were investigated. Despite the decreased carrier density in the annealed ZnO thin films, the conductivity was increased because the contribution of the effective carrier mobility to the conductivity of the unintentionally-doped ZnO thin films is greater than that of the carrier density. The resistivity exponentially decreased with increasing RTA temperature, and this result was confirmed to come from the enhanced effective carrier-mobility, which originated from the increased crystallite size in the annealed ZnO thin films.

  5. Sputtered Modified Barium Titanate for Thin-Film Capacitor Applications

    Directory of Open Access Journals (Sweden)

    Robert Mamazza

    2012-04-01

    Full Text Available New apparatus and a new process for the sputter deposition of modified barium titanate thin-films were developed. Films were deposited at temperatures up to 900 °C from a Ba0.96Ca0.04Ti0.82Zr0.18O3 (BCZTO target directly onto Si, Ni and Pt surfaces and characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM and X-ray photoelectron spectroscopy (XPS. Film texture and crystallinity were found to depend on both deposition temperature and substrate: above 600 °C, the as-deposited films consisted of well-facetted crystallites with the cubic perovskite structure. A strongly textured Pt (111 underlayer enhanced the (001 orientation of BCZTO films deposited at 900 °C, 10 mtorr pressure and 10% oxygen in argon. Similar films deposited onto a Pt (111 textured film at 700 °C and directly onto (100 Si wafers showed relatively larger (011 and diminished intensity (00ℓ diffraction peaks. Sputter ambients containing oxygen caused the Ni underlayers to oxidize even at 700 °C: Raising the process temperature produced more diffraction peaks of NiO with increased intensities. Thin-film capacitors were fabricated using ~500 nm thick BCZTO dielectrics and both Pt and Ni top and bottom electrodes. Small signal capacitance measurements were carried out to determine capacitance and parallel resistance at low frequencies and from these data, the relative permittivity (er and resistivity (r of the dielectric films were calculated; values ranged from ~50 to >2,000, and from ~104 to ~1010 Ω∙cm, respectively.

  6. Influence of lithium doping on the structural and electrical characteristics of ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Johny, T. Anto [Centre for Materials for Electronics Technology (C-MET), (Department of Information Technology, Scientific Society, Ministry of Communication and Information Technology, Govt. of India), Athani - PO, Thrissur, 680 581 Kerala (India); Kumar, Viswanathan, E-mail: vkumar10@yahoo.com [Centre for Materials for Electronics Technology (C-MET), (Department of Information Technology, Scientific Society, Ministry of Communication and Information Technology, Govt. of India), Athani - PO, Thrissur, 680 581 Kerala (India); Imai, Hideyuki; Kanno, Isaku [Micro Engineering, Kyoto University, Kyoto 606-8501 (Japan)

    2012-06-30

    Thin films of undoped and lithium-doped Zinc oxide, (Zn{sub 1-x}Li{sub x})O; x = 0, 0.05, 0.10 and 0.20 were prepared by sol-gel method using spin-coating technique on silicon substrates [(111)Pt/Ti/SiO{sub 2}/Si)]. The influence of lithium doping on the structural, electrical and microstructural characteristics have been investigated by means of X-ray diffraction, leakage current, piezoelectric measurements and scanning electron microscopy. The resistivity of the ZnO film is found to increase markedly with low levels (x {<=} 0.05) of lithium doping thereby enhancing their piezoelectric applications. The transverse piezoelectric coefficient, e{sub 31}{sup Low-Asterisk} has been determined for the thin films having the composition (Zn{sub 0.95}Li{sub 0.05})O, to study their suitability for piezoelectric applications. - Highlights: Black-Right-Pointing-Pointer Preferentially c-axis oriented (Zn{sub 1-x}Li{sub x})O films were spin-coated on glass. Black-Right-Pointing-Pointer (Zn{sub 1-x}Li{sub x})O thin films exhibit dense columnar microstructure. Black-Right-Pointing-Pointer Low levels of lithium doping, increases the electrical resistivity of ZnO thin films. Black-Right-Pointing-Pointer (Zn{sub 1-x}Li{sub x})O thin films show high values of transverse piezoelectric coefficient, e{sup Low-Asterisk }{sub 31}.

  7. Atomic layer deposition of copper thin film and feasibility of deposition on inner walls of waveguides

    Science.gov (United States)

    Yuqing, XIONG; Hengjiao, GAO; Ni, REN; Zhongwei, LIU

    2018-03-01

    Copper thin films were deposited by plasma-enhanced atomic layer deposition at low temperature, using copper(I)-N,N‧-di-sec-butylacetamidinate as a precursor and hydrogen as a reductive gas. The influence of temperature, plasma power, mode of plasma, and pulse time, on the deposition rate of copper thin film, the purity of the film and the step coverage were studied. The feasibility of copper film deposition on the inner wall of a carbon fibre reinforced plastic waveguide with high aspect ratio was also studied. The morphology and composition of the thin film were studied by atomic force microscopy and x-ray photoelectron spectroscopy, respectively. The square resistance of the thin film was also tested by a four-probe technique. On the basis of on-line diagnosis, a growth mechanism of copper thin film was put forward, and it was considered that surface functional group played an important role in the process of nucleation and in determining the properties of thin films. A high density of plasma and high free-radical content were helpful for the deposition of copper thin films.

  8. Biomimetic thin film synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Graff, G.L.; Campbell, A.A.; Gordon, N.R.

    1995-05-01

    The purpose of this program is to develop a new process for forming thin film coatings and to demonstrate that the biomimetic thin film technology developed at PNL is useful for industrial applications. In the biomimetic process, mineral deposition from aqueous solution is controlled by organic functional groups attached to the underlying substrate surface. The coatings process is simple, benign, inexpensive, energy efficient, and particularly suited for temperature sensitive substrate materials (such as polymers). In addition, biomimetic thin films can be deposited uniformly on complex shaped and porous substrates providing a unique capability over more traditional line-of-sight methods.

  9. Reliability assessment of ultra-thin HfO2 films deposited on silicon wafer

    International Nuclear Information System (INIS)

    Fu, Wei-En; Chang, Chia-Wei; Chang, Yong-Qing; Yao, Chih-Kai; Liao, Jiunn-Der

    2012-01-01

    Highlights: ► Nano-mechanical properties on annealed ultra-thin HfO 2 film are studied. ► By AFM analysis, hardness of the crystallized HfO 2 film significantly increases. ► By nano-indention, the film hardness increases with less contact stiffness. ► Quality assessment on the annealed ultra-thin films can thus be achieved. - Abstract: Ultra-thin hafnium dioxide (HfO 2 ) is used to replace silicon dioxide to meet the required transistor feature size in advanced semiconductor industry. The process integration compatibility and long-term reliability for the transistors depend on the mechanical performance of ultra-thin HfO 2 films. The criteria of reliability including wear resistance, thermal fatigue, and stress-driven failure rely on film adhesion significantly. The adhesion and variations in mechanical properties induced by thermal annealing of the ultra-thin HfO 2 films deposited on silicon wafers (HfO 2 /SiO 2 /Si) are not fully understood. In this work, the mechanical properties of an atomic layer deposited HfO 2 (nominal thickness ≈10 nm) on a silicon wafer were characterized by the diamond-coated tip of an atomic force microscope and compared with those of annealed samples. The results indicate that the annealing process leads to the formation of crystallized HfO 2 phases for the atomic layer deposited HfO 2 . The HfSi x O y complex formed at the interface between HfO 2 and SiO 2 /Si, where the thermal diffusion of Hf, Si, and O atoms occurred. The annealing process increases the surface hardness of crystallized HfO 2 film and therefore the resistance to nano-scratches. In addition, the annealing process significantly decreases the harmonic contact stiffness (or thereafter eliminate the stress at the interface) and increases the nano-hardness, as measured by vertically sensitive nano-indentation. Quality assessments on as-deposited and annealed HfO 2 films can be thereafter used to estimate the mechanical properties and adhesion of ultra-thin HfO 2

  10. Solid-phase crystallization of amorphous silicon on ZnO:Al for thin-film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Becker, C.; Conrad, E.; Dogan, P.; Fenske, F.; Gorka, B.; Haenel, T.; Lee, K.Y.; Rau, B.; Ruske, F.; Weber, T.; Gall, S.; Rech, B. [Helmholtz-Zentrum Berlin fuer Materialien und Energie (formerly Hahn-Meitner-Institut Berlin), Kekulestr. 5, D-12489 Berlin (Germany); Berginski, M.; Huepkes, J. [Institute of Photovoltaics, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)

    2009-06-15

    The suitability of ZnO:Al thin films for polycrystalline silicon (poly-Si) thin-film solar cell fabrication was investigated. The electrical and optical properties of 700 -nm-thick ZnO:Al films on glass were analyzed after typical annealing steps occurring during poly-Si film preparation. If the ZnO:Al layer is covered by a 30 nm thin silicon film, the initial sheet resistance of ZnO:Al drops from 4.2 to 2.2 {omega} after 22 h annealing at 600 C and only slightly increases for a 200 s heat treatment at 900 C. A thin-film solar cell concept consisting of poly-Si films on ZnO:Al coated glass is introduced. First solar cell results will be presented using absorber layers either prepared by solid-phase crystallization (SPC) or by direct deposition at 600 C. (author)

  11. Characterization of room temperature recrystallization kinetics in electroplated copper thin films with concurrent x-ray diffraction and electrical resistivity measurements

    Energy Technology Data Exchange (ETDEWEB)

    Treger, Mikhail; Noyan, I. C. [Department of Applied Physics and Applied Mathematics, Columbia University, New York 10027 (United States); Witt, Christian [GlobalFoundries, T.J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Cabral, Cyril; Murray, Conal; Jordan-Sweet, Jean [IBM, T.J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Rosenberg, Robert [State University of New York, the University at Albany, Albany, NY 12203 (United States); Eisenbraun, Eric [College of Nanoscale Science and Engineering, University at Albany, Albany, NY 12203 (United States)

    2013-06-07

    Concurrent in-situ four-point probe resistivity and high resolution synchrotron x-ray diffraction measurements were used to characterize room temperature recrystallization in electroplated Cu thin films. The x-ray data were used to obtain the variation with time of the integrated intensities and the peak-breadth from the Cu 111 and 200 reflections of the transforming grains. The variation of the integrated intensity and resistivity data with time was analyzed using the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model. For both 111-textured and non-textured electroplated Cu films, four-point probe resistivity measurements yielded shorter transformation times than the values obtained from the integrated intensities of the corresponding Cu 111 reflections. In addition, the JMAK exponents fitted to the resistivity data were significantly smaller. These discrepancies could be explained by considering the different material volumes from which resistivity and diffraction signals originated, and the physical processes which linked these signals to the changes in the evolving microstructure. Based on these issues, calibration of the resistivity analysis with direct structural characterization techniques is recommended.

  12. Thin Film Photovoltaic Partnership Project | Photovoltaic Research | NREL

    Science.gov (United States)

    Thin Film Photovoltaic Partnership Project Thin Film Photovoltaic Partnership Project NREL's Thin Film Photovoltaic (PV) Partnership Project led R&D on emerging thin-film solar technologies in the United States from 1994 to 2009. The project made many advances in thin-film PV technologies that allowed

  13. Thin Film & Deposition Systems (Windows)

    Data.gov (United States)

    Federal Laboratory Consortium — Coating Lab: Contains chambers for growing thin film window coatings. Plasma Applications Coating Lab: Contains chambers for growing thin film window coatings. Solar...

  14. Electrical resistivity change in Al:ZnO thin films dynamically deposited by bipolar pulsed direct-current sputtering and a remote plasma source

    International Nuclear Information System (INIS)

    Yang, Wonkyun; Joo, Junghoon

    2010-01-01

    The Al-doped ZnO (AZO) thin films for a transparent conducting oxide in solar cell devices were deposited by bipolar pulsed dc magnetron sputtering. This work was performed in an in-line type system and investigated AZO films in a static deposition mode and dynamic one, which is more important in the practical fields. Because of this dynamic deposition process, the zigzagged columnar structure was observed. This resulted in the decreasing electrical property, optical properties, and surface roughness. As a deposition in the dynamic mode, the resistivity increased from 1.64x10 -3 to 2.50x10 -3 Ω cm, as compared to that in the static mode, and the transmittance also decreased from 83.9% to 78.3%. To recover the disadvantage, a remote plasma source (RPS) was supported between the substrate and target for reducing zigzagged formation during the deposition. The deposition rate decreased by using RPS, but the electrical and optical properties of films got better than only dynamic mode. The resistivity and transmittance in the dynamic mode using RPS were 2.1x10 -3 Ω cm and 85.5%, respectively. In this study, the authors found the possibility to advance the electrical and optical properties of AZO thin films in the industry mode.

  15. Amorphous indium gallium zinc oxide thin film grown by pulse laser deposition technique

    Energy Technology Data Exchange (ETDEWEB)

    Mistry, Bhaumik V., E-mail: bhaumik-phy@yahoo.co.in; Joshi, U. S. [Department of Physics, University School of Sciences, Gujarat University, Ahmedabad-380 009 (India)

    2016-05-23

    Highly electrically conducting and transparent in visible light IGZO thin film were grown on glass substrate at substrate temperature of 400 C by a pulse laser deposition techniques. Structural, surface, electrical, and optical properties of IGZO thin films were investigated at room temperature. Smooth surface morphology and amorphous nature of the film has been confirmed from the AFM and GIXRD analysis. A resistivity down to 7.7×10{sup −3} V cm was reproducibly obtained while maintaining optical transmission exceeding 70% at wavelengths from 340 to 780 nm. The carrier densities of the film was obtain to the value 1.9×10{sup 18} cm{sup 3}, while the Hall mobility of the IGZO thin film was 16 cm{sup 2} V{sup −1}S{sup −1}.

  16. Optoelectronic properties of doped hydrothermal ZnO thin films

    KAUST Repository

    Mughal, Asad J.

    2017-03-10

    Group III impurity doped ZnO thin films were deposited on MgAl2O3 substrates using a simple low temperature two-step deposition method involving atomic layer deposition and hydrothermal epitaxy. Films with varying concentrations of either Al, Ga, or In were evaluated for their optoelectronic properties. Inductively coupled plasma atomic emission spectroscopy was used to determine the concentration of dopants within the ZnO films. While Al and Ga-doped films showed linear incorporation rates with the addition of precursors salts in the hydrothermal growth solution, In-doped films were shown to saturate at relatively low concentrations. It was found that Ga-doped films showed the best performance in terms of electrical resistivity and optical absorbance when compared to those doped with In or Al, with a resistivity as low as 1.9 mΩ cm and an optical absorption coefficient of 441 cm−1 at 450 nm.

  17. Influence of sputtering power on the optical properties of ITO thin films

    Energy Technology Data Exchange (ETDEWEB)

    K, Aijo John; M, Deepak, E-mail: manju.thankamoni@gmail.com; T, Manju, E-mail: manju.thankamoni@gmail.com [Department of Physics, Sree Sankara College, Kalady P. O., Ernakulam Dist., Kerala (India); Kumar, Vineetha V. [Dept. of Physics, K. E. College, Mannanam, Kottayam Dist., Kerala (India)

    2014-10-15

    Tin doped indium oxide films are widely used in transparent conducting coatings such as flat panel displays, crystal displays and in optical devices such as solar cells and organic light emitting diodes due to the high electrical resistivity and optical transparency in the visible region of solar spectrum. The deposition parameters have a commendable influence on the optical and electrical properties of the thin films. In this study, ITO thin films were prepared by RF magnetron sputtering. The properties of the films prepared under varying sputtering power were compared using UV- visible spectrophotometry. Effect of sputtering power on the energy band gap, absorption coefficient and refractive index are investigated.

  18. Topological Insulator State in Thin Bismuth Films Subjected to Plane Tensile Strain

    Science.gov (United States)

    Demidov, E. V.; Grabov, V. M.; Komarov, V. A.; Kablukova, N. S.; Krushel'nitskii, A. N.

    2018-03-01

    The results of experimental examination of galvanomagnetic properties of thin bismuth films subjected to plane tensile strain resulting from the difference in thermal expansion coefficients of the substrate material and bismuth are presented. The resistivity, the magnetoresistance, and the Hall coefficient were studied at temperatures ranging from 5 to 300 K in magnetic fields as strong as 0.65 T. Carrier densities were calculated. A considerable increase in carrier density in films thinner than 30 nm was observed. This suggests that surface states are more prominent in thin bismuth films on mica substrates, while the films themselves may exhibit the properties of a topological insulator.

  19. Structural and optical properties of DC reactive magnetron sputtered zinc aluminum oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, B. Rajesh, E-mail: rajphyind@gmail.com [Department of Physics, GITAM Institute of Technology, GITAM University, Visakhapatnam - 530 045, A.P. (India); Rao, T. Subba, E-mail: thotasubbarao6@gmail.com [Department of Physics, Sri Krishnadevaraya University, Anantapuramu - 515 003, A.P. (India)

    2014-10-15

    Highly transparent conductive Zinc Aluminum Oxide (ZAO) thin films have been deposited on glass substrates using DC reactive magnetron sputtering method. The thin films were deposited at 200 °C and post-deposition annealing from 15 to 90 min. XRD patterns of ZAO films exhibit only (0 0 2) diffraction peak, indicating that they have c-axis preferred orientation perpendicular to the substrate. Scanning electron microscopy (SEM) is used to study the surface morphology of the films. The grain size obtained from SEM images of ZAO thin films are found to be in the range of 20 - 26 nm. The minimum resistivity of 1.74 × 10{sup −4} Ω cm and an average transmittance of 92% are obtained for the thin film post annealed for 30 min. The optical band gap of ZAO thin films increased from 3.49 to 3.60 eV with the increase of annealing time due to Burstein-Moss effect. The optical constants refractive index (n) and extinction coefficient (k) were also determined from the optical transmission spectra.

  20. Hybrid composite thin films composed of tin oxide nanoparticles and cellulose

    International Nuclear Information System (INIS)

    Mahadeva, Suresha K; Nayak, Jyoti; Kim, Jaehwan

    2013-01-01

    This paper reports the preparation and characterization of hybrid thin films consisting of tin oxide (SnO 2 ) nanoparticles and cellulose. SnO 2 nanoparticle loaded cellulose hybrid thin films were fabricated by a solution blending technique, using sodium dodecyl sulfate as a dispersion agent. Scanning and transmission electron microscopy studies revealed uniform dispersion of the SnO 2 nanoparticles in the cellulose matrix. Reduction in the crystalline melting transition temperature and tensile properties of cellulose was observed due to the SnO 2 nanoparticle loading. Potential application of these hybrid thin films as low cost, flexible and biodegradable humidity sensors is examined in terms of the change in electrical resistivity of the material exposed to a wide range of humidity as well as its response–recovery behavior. (paper)

  1. Investigation of the Optoelectronic Properties of Ti-doped Indium Tin Oxide Thin Film.

    Science.gov (United States)

    Pu, Nen-Wen; Liu, Wei-Sheng; Cheng, Huai-Ming; Hu, Hung-Chun; Hsieh, Wei-Ting; Yu, Hau-Wei; Liang, Shih-Chang

    2015-09-21

    : In this study, direct-current magnetron sputtering was used to fabricate Ti-doped indium tin oxide (ITO) thin films. The sputtering power during the 350-nm-thick thin-film production process was fixed at 100 W with substrate temperatures increasing from room temperature to 500 °C. The Ti-doped ITO thin films exhibited superior thin-film resistivity (1.5 × 10 - ⁴ Ω/cm), carrier concentration (4.1 × 10 21 cm - ³), carrier mobility (10 cm²/Vs), and mean visible-light transmittance (90%) at wavelengths of 400-800 nm at a deposition temperature of 400 °C. The superior carrier concentration of the Ti-doped ITO alloys (>10 21 cm - ³) with a high figure of merit (81.1 × 10 - ³ Ω - ¹) demonstrate the pronounced contribution of Ti doping, indicating their high suitability for application in optoelectronic devices.

  2. Growth of high-quality large-area MgB2 thin films by reactive evaporation

    International Nuclear Information System (INIS)

    Moeckly, B H; Ruby, W S

    2006-01-01

    We report a new in situ reactive deposition thin film growth technique for the production of MgB 2 thin films which offers several advantages over all existing methods and is the first deposition method to enable the production of high-quality MgB 2 films for real-world applications. We have used this growth method, which incorporates a rotating pocket heater, to deposit MgB 2 films on a variety of substrates, including single-crystalline, polycrystalline, metallic, and semiconductor materials up to 4 inch in diameter. This technique allows growth of double-sided, large-area films in the intermediate temperature range of 400-600 deg. C. These films are clean, well-connected, and consistently display T c values of 38-39 K with low resistivity and residual resistivity values. They are also robust and uncommonly stable upon exposure to atmosphere and water. (rapid communication)

  3. Growth of conductive HfO{sub 2-x} thin films by reactive molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrandt, Erwin; Kurian, Jose; Alff, Lambert [Institut fuer Materialwissenschaft, TU Darmstadt (Germany); Kleebe, Hans-Joachim [Institut fuer Angewandte Geowissenschaften, TU Darmstadt (Germany)

    2009-07-01

    Thin films of oxygen deficient hafnium oxide were grown on single crystal c-cut and r-cut sapphire substrates by reactive molecular beam epitaxy. The oxidation conditions during growth were varied within a wide range using RF-activated oxygen. Hafnium oxide thin films were characterized using X-ray diffraction, resistivity measurements ({rho}-T) and transmission electron microscopy (TEM). The results show a dramatic increase in conductivity of the deposited oxygen deficient hafnium oxide thin films with decreasing oxidation conditions during growth. The electrical properties of deficient hafnium oxide thin films varied from insulating over semiconducting to conducting. X-ray diffraction data as well as TEM data rule out the possibility of conductivity due to metallic hafnium.

  4. Curious resistivity behaviour of vacuum evaporated Er, Dy and Gd films

    International Nuclear Information System (INIS)

    Saxena, U.; Kaul, V.K.; Bist, B.M.; Srivastava, O.N.

    1976-01-01

    The thickness dependence of electrical resistivity of Er, Dy and Gd thin films at room temperature has been studied. The electrical resistivity of these films does not show the usual behaviour expected on the basis of the size affected conduction i.e. Fuchs Sondheimer theory, which always leads to an increase in the resistivity with decreasing film thickness. Instead, the observed resistivity behaviour is characterised mainly by (i) a decrease in resistivity with decreasing film thickness (between 1600-1000 deg A) for Er films and below about 500 deg A for Gd and Dy films), (ii) a thickness independent resistivity behaviour for Er films from 1000-600 deg A, (iii) increase in resistivity of Er films in the thickness region 600-200 deg A, (iv) the resistivity values in certain thickness regions, which are even less than the corresponding bulk value. Analysis reveals that those curious rho-t characteristics arise due to three effects namely, the increase resistivity due to surface scattering the suppression of resistivity due to thickness dependence of structural phase and spin disorder scattering. All the effects are dominant in thickness regions, different in different metals giving rise to the observed characteristics. (author)

  5. Preparation and study of nanostructured TiAlSiN thin films

    Directory of Open Access Journals (Sweden)

    Jakab-Farkas L.

    2011-12-01

    Full Text Available TiAlSiN thin film coatings were deposited by DC reactive magnetron sputtering of TiAlSi target with 40 at.% Ti, 40 at.% Al and 20 at.% Si, performed in N2-Ar gas mixture. The sputtering power used in these experiments was controlled for 400 W. The bias voltage of the substrates was kept at -20 V DC and the temperature at 500 0C. All the samples were prepared with a constant flow rate of Ar and different nitrogen flow rates, which were selected from 1.25 sccm to 4.0 sccm. Nanostructured TiAlSiN coatings were developed on Si(100 and HSS substrates. Microstructure investigation of the coatings was performed by transmission electron microscopy investigation, structure investigation was performed by XRD analysis, and the mechanical properties of the coatings have been tested by ball-on-disk tribological investigation and micro-Vickers hardness measurements. In this paper will be shown that for optimized nitrogen concentration the microstructure of TiAlSiN coating evolve from a competitive columnar growth to a dendritic growth one with very fine nano-lamellae like morphology. The developed nanostructured TiAlSiN coatingshave hardness HV exceeding 40 GPa and show an increased abrasive wear resistance

  6. Characterization of organic thin films

    CERN Document Server

    Ulman, Abraham; Evans, Charles A

    2009-01-01

    Thin films based upon organic materials are at the heart of much of the revolution in modern technology, from advanced electronics, to optics to sensors to biomedical engineering. This volume in the Materials Characterization series introduces the major common types of analysis used in characterizing of thin films and the various appropriate characterization technologies for each. Materials such as Langmuir-Blodgett films and self-assembled monolayers are first introduced, followed by analysis of surface properties and the various characterization technologies used for such. Readers will find detailed information on: -Various spectroscopic approaches to characterization of organic thin films, including infrared spectroscopy and Raman spectroscopy -X-Ray diffraction techniques, High Resolution EELS studies, and X-Ray Photoelectron Spectroscopy -Concise Summaries of major characterization technologies for organic thin films, including Auger Electron Spectroscopy, Dynamic Secondary Ion Mass Spectrometry, and Tra...

  7. Double-layer indium doped zinc oxide for silicon thin-film solar cell prepared by ultrasonic spray pyrolysis

    International Nuclear Information System (INIS)

    Jiao Bao-Chen; Zhang Xiao-Dan; Wei Chang-Chun; Sun Jian; Ni Jian; Zhao Ying

    2011-01-01

    Indium doped zinc oxide (ZnO:In) thin films were prepared by ultrasonic spray pyrolysis on corning eagle 2000 glass substrate. 1 and 2 at.% indium doped single-layer ZnO:In thin films with different amounts of acetic acid added in the initial solution were fabricated. The 1 at.% indium doped single-layers have triangle grains. The 2 at.% indium doped single-layer with 0.18 acetic acid adding has the resistivity of 6.82×10 −3 Ω·cm and particle grains. The double-layers structure is designed to fabricate the ZnO:In thin film with low resistivity (2.58×10 −3 Ω·cm) and good surface morphology. It is found that the surface morphology of the double-layer ZnO:In film strongly depends on the substrate-layer, and the second-layer plays a large part in the resistivity of the double-layer ZnO:In thin film. Both total and direct transmittances of the double-layer ZnO:In film are above 80% in the visible light region. Single junction a-Si:H solar cell based on the double-layer ZnO:In as front electrode is also investigated. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  8. Excimer laser sintering of indium tin oxide nanoparticles for fabricating thin films of variable thickness on flexible substrates

    International Nuclear Information System (INIS)

    Park, Taesoon; Kim, Dongsik

    2015-01-01

    Technology to fabricate electrically-conducting, transparent thin-film patterns on flexible substrates has possible applications in flexible electronics. In this work, a pulsed-laser sintering process applicable to indium tin oxide (ITO) thin-film fabrication on a substrate without thermal damage to the substrate was developed. A nanosecond pulsed laser was used to minimize thermal penetration into the substrate and to control the thickness of the sintered layer. ITO nanoparticles (NPs) of ~ 20 nm diameter were used to lower the process temperature by exploiting their low melting point. ITO thin film patterns were fabricated by first spin coating the NPs onto a surface, then sintering them using a KrF excimer laser. The sintered films were characterized using field emission scanning electron microscopy. The electrical resistivity and transparency of the film were measured by varying the process parameters. A single laser pulse could generate the polycrystalline structure (average grain size ~ 200 nm), reducing the electrical resistivity of the film by a factor of ~ 1000. The sintering process led to a minimum resistivity of 1.1 × 10 −4 Ω·m without losing the transparency of the film. The thickness of the sintered layer could be varied up to 150 nm by adjusting the laser fluence. Because the estimated thermal penetration depth in the ITO film was less than 200 nm, no thermal damage was observed in the substrate. This work suggests that the proposed process, combined with various particle deposition methods, can be an effective tool to form thin-film ITO patterns on flexible substrates. - Highlights: • Excimer laser sintering can fabricate ITO thin films on flexible substrates. • The laser pulse can form a polycrystalline structure without thermal damage. • The laser sintering process can reduce the electrical resistivity substantially. • The thickness of the sintered layer can be varied effectively

  9. Excimer laser sintering of indium tin oxide nanoparticles for fabricating thin films of variable thickness on flexible substrates

    Energy Technology Data Exchange (ETDEWEB)

    Park, Taesoon; Kim, Dongsik, E-mail: dskim87@postech.ac.kr

    2015-03-02

    Technology to fabricate electrically-conducting, transparent thin-film patterns on flexible substrates has possible applications in flexible electronics. In this work, a pulsed-laser sintering process applicable to indium tin oxide (ITO) thin-film fabrication on a substrate without thermal damage to the substrate was developed. A nanosecond pulsed laser was used to minimize thermal penetration into the substrate and to control the thickness of the sintered layer. ITO nanoparticles (NPs) of ~ 20 nm diameter were used to lower the process temperature by exploiting their low melting point. ITO thin film patterns were fabricated by first spin coating the NPs onto a surface, then sintering them using a KrF excimer laser. The sintered films were characterized using field emission scanning electron microscopy. The electrical resistivity and transparency of the film were measured by varying the process parameters. A single laser pulse could generate the polycrystalline structure (average grain size ~ 200 nm), reducing the electrical resistivity of the film by a factor of ~ 1000. The sintering process led to a minimum resistivity of 1.1 × 10{sup −4} Ω·m without losing the transparency of the film. The thickness of the sintered layer could be varied up to 150 nm by adjusting the laser fluence. Because the estimated thermal penetration depth in the ITO film was less than 200 nm, no thermal damage was observed in the substrate. This work suggests that the proposed process, combined with various particle deposition methods, can be an effective tool to form thin-film ITO patterns on flexible substrates. - Highlights: • Excimer laser sintering can fabricate ITO thin films on flexible substrates. • The laser pulse can form a polycrystalline structure without thermal damage. • The laser sintering process can reduce the electrical resistivity substantially. • The thickness of the sintered layer can be varied effectively.

  10. Electrical and optical properties of Zn–In–Sn–O transparent conducting thin films

    International Nuclear Information System (INIS)

    Carreras, Paz; Antony, Aldrin; Rojas, Fredy; Bertomeu, Joan

    2011-01-01

    Indium tin oxide (ITO) is one of the widely used transparent conductive oxides (TCO) for application as transparent electrode in thin film silicon solar cells or thin film transistors owing to its low resistivity and high transparency. Nevertheless, indium is a scarce and expensive element and ITO films require high deposition temperature to achieve good electrical and optical properties. On the other hand, although not competing as ITO, doped Zinc Oxide (ZnO) is a promising and cheaper alternative. Therefore, our strategy has been to deposit ITO and ZnO multicomponent thin films at room temperature by radiofrequency (RF) magnetron co-sputtering in order to achieve TCOs with reduced indium content. Thin films of the quaternary system Zn–In–Sn–O (ZITO) with improved electrical and optical properties have been achieved. The samples were deposited by applying different RF powers to ZnO target while keeping a constant RF power to ITO target. This led to ZITO films with zinc content ratio varying between 0 and 67%. The optical, electrical and morphological properties have been thoroughly studied. The film composition was analysed by X-ray Photoelectron Spectroscopy. The films with 17% zinc content ratio showed the lowest resistivity (6.6 × 10 −4 Ω cm) and the highest transmittance (above 80% in the visible range). Though X-ray Diffraction studies showed amorphous nature for the films, using High Resolution Transmission Electron Microscopy we found that the microstructure of the films consisted of nanometric crystals embedded in a compact amorphous matrix. The effect of post deposition annealing on the films in both reducing and oxidizing atmospheres were studied. The changes were found to strongly depend on the zinc content ratio in the films.

  11. Deposition and characterization of ZrMoN thin films by reactive magnetron sputtering

    International Nuclear Information System (INIS)

    Fontes Junir, A.S.; Felix, L.C.; Oliveira, G.B. de; Fernandez, D.R.; Carvalho, R.G.; Tentardini, E.K.; Silva Junior, A.H. da

    2016-01-01

    Thin films of ZrMoN were deposited by magnetron reactive sputtering technique in order to study the molybdenum influence on the mechanical properties and oxidation resistance of these coatings. Three thin films with molybdenum concentrations from 25 to 40 at.% were selected. The displacement of characteristic peaks of ZrN where identified by GIXRD results of films with larger Mo content. This result is indicative of the Mo accommodation in the lattice structure. Hardness tests revealed favorable results with values up to 33 GPa. Oxidation tests showed that ZrN oxidized at 500 °C with a monoclinic ZrO 2 and tetragonal formation; whereas the thin films with Mo addition impeded the formation of the monoclinic ZrO 2 phase at partial oxidation. (author)

  12. TiO2 and Cu/TiO2 Thin Films Prepared by SPT

    Directory of Open Access Journals (Sweden)

    S. S. Roy

    2015-12-01

    Full Text Available Titanium oxide (TiO2 and copper (Cu doped titanium oxide (Cu/TiO2 thin films have been prepared by spray pyrolysis technique. Titanium chloride (TiCl4 and copper acetate (Cu(CH3COO2.H2O were used as source of Ti and Cu. The doping concentration of Cu was varied from 1-10 wt. %. The X-ray diffraction studies show that TiO2 thin films are tetragonal structure and Cu/TiO2 thin films implies CuO has present with monoclinic structure. The optical properties of the TiO2 thin films have been investigated as a function of Cu-doping level. The optical transmission of the thin films was found to increase from 88 % to 94 % with the addition of Cu up to 8 % and then decreases for higher percentage of Cu doping. The optical band gap (Eg for pure TiO2 thin film is found to be 3.40 eV. Due to Cu doping, the band gap is shifted to lower energies and then increases further with increasing the concentration of Cu. The refractive index of the TiO2 thin films is found to be 2.58 and the variation of refractive index is observed due to Cu doped. The room temperature resistivity of the films decreases with increasing Cu doping and is found to be 27.50 - 23.76 W·cm. It is evident from the present study that the Cu doping promoted the thin film morphology and thereby it is aspect for various applications.

  13. Effects of Aloe Vera and Chitosan Nanoparticle Thin-Film Membranes on Wound Healing in Full Thickness Infected Wounds with Methicillin Resistant Staphylococcus Aureus.

    Science.gov (United States)

    Ranjbar, Reza; Yousefi, Alireza

    2018-01-01

    To assess effect of Aleo vera with chitosan nanoparticle biofilm on wound healing in full thickness infected wounds with antibiotic resistant gram positive bacteria. Thirty rats were randomized into five groups of six rats each. Group I: Animals with uninfected wounds treated with 0.9% saline solution. Group II: Animals with infected wounds treated with saline. Group III: Animals with infected wounds were dressed with chitosan nanoparticle thin-film membranes. Group IV: Animals with infected wounds were treated topically with Aloe vera and Group V: Animals with infected wounds were treated topically with Aloe vera and dressed with chitosan nanoparticle thin-film membranes. Wound size was measured on 6, 9, 12, 15, 18 and 21days after surgery. Microbiology, reduction in wound area and hydroxyproline contents indicated that there was significant difference ( p vera with chitosan nanoparticle thin-film membranes had a reproducible wound healing potential and hereby justified its use in practice.

  14. Polarization fatigue resistance of Ca-doped Pb(Zr0.52Ti0.48)O3 thin films prepared by the sol-gel method

    International Nuclear Information System (INIS)

    Wei, T.; Wang, Y.; Zhu, C.; Dong, X.W.; Xia, Y.D.; Zhu, J.S.; Liu, J.-M.

    2008-01-01

    The ferroelectric and polarization fatigue characteristics of Pb 1-x Ca x (Zr 0.52 Ti 0.48 )O 3 (PCZT) thin films prepared using the sol-gel method were studied. The Ca-doping slightly suppresses the ferroelectricity of Pb(Zr 0.52 Ti 0.48 )O 3 (PZT) because of the quantum paraelectric behavior of CaTiO 3 . Compared with PZT thin films, the PCZT (x=0.2) thin films show enhanced fatigue resistance at room temperature, further emphasized by the almost fatigue-free behavior at 100 K. The temperature-dependent dc-conductivity suggests a decrease of the oxygen vacancy density by almost 20 times and a slightly declined activation energy U for oxygen vacancies, upon increasing of the Ca-doping content from 0.0 to 0.2. It is argued that the improved fatigue endurance is ascribed to the decreasing density of oxygen vacancies due to the Ca-doping, although the lowered activation energy of oxygen vacancies is unfavorable. (orig.)

  15. The Effect of Microstructure on the Abrasion Resistance of Low Alloyed Steels

    NARCIS (Netherlands)

    Xu, X.

    2016-01-01

    The thesis attempts to develop advanced high abrasion resistant steels with low hardness in combination with good toughness, processability and low alloying additions. For this purpose, a novel multi-pass dual-indenter (MPDI) scratch test approach has been developed to approach the real continuous

  16. Fracture toughness improvements of dental ceramic through use of yttria-stabilized zirconia (YSZ) thin-film coatings.

    Science.gov (United States)

    Chan, Ryan N; Stoner, Brian R; Thompson, Jeffrey Y; Scattergood, Ronald O; Piascik, Jeffrey R

    2013-08-01

    The aim of this study was to evaluate strengthening mechanisms of yttria-stabilized zirconia (YSZ) thin film coatings as a viable method for improving fracture toughness of all-ceramic dental restorations. Bars (2mm×2mm×15mm, n=12) were cut from porcelain (ProCAD, Ivoclar-Vivadent) blocks and wet-polished through 1200-grit using SiC abrasive. A Vickers indenter was used to induce flaws with controlled size and geometry. Depositions were performed via radio frequency magnetron sputtering (5mT, 25°C, 30:1 Ar/O2 gas ratio) with varying powers of substrate bias. Film and flaw properties were characterized by optical microscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD). Flexural strength was determined by three-point bending. Fracture toughness values were calculated from flaw size and fracture strength. Data show improvements in fracture strength of up to 57% over unmodified specimens. XRD analysis shows that films deposited with higher substrate bias displayed a high %monoclinic volume fraction (19%) compared to non-biased deposited films (87%), and resulted in increased film stresses and modified YSZ microstructures. SEM analysis shows critical flaw sizes of 67±1μm leading to fracture toughness improvements of 55% over unmodified specimens. Data support surface modification of dental ceramics with YSZ thin film coatings to improve fracture toughness. Increase in construct strength was attributed to increase in compressive film stresses and modified YSZ thin film microstructures. It is believed that this surface modification may lead to significant improvements and overall reliability of all-ceramic dental restorations. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  17. Annealing of SnO2 thin films by ultra-short laser pulses

    NARCIS (Netherlands)

    Scorticati, D.; Illiberi, A.; Bor, T.; Eijt, S.W.H.; Schut, H.; Römer, G.R.B.E.; Lange, D.F. de; Huis In't Veld, A.J.

    2014-01-01

    Post-deposition annealing by ultra-short laser pulses can modify the optical properties of SnO2 thin films by means of thermal processing. Industrial grade SnO2 films exhibited improved optical properties after picosecond laser irradiation, at the expense of a slightly increased sheet resistance

  18. Preparation of anatase TiO2 thin films by vacuum arc plasma evaporation

    International Nuclear Information System (INIS)

    Miyata, Toshihiro; Tsukada, Satoshi; Minami, Tadatsugu

    2006-01-01

    Anatase titanium dioxide (TiO 2 ) thin films with high photocatalytic activity have been prepared with deposition rates as high as 16 nm/min by a newly developed vacuum arc plasma evaporation (VAPE) method using sintered TiO 2 pellets as the source material. Highly transparent TiO 2 thin films prepared at substrate temperatures from room temperature to 400 deg. C exhibited photocatalytic activity, regardless whether oxygen (O 2 ) gas was introduced during the VAPE deposition. The highest photocatalytic activity and photo-induced hydrophilicity were obtained in anatase TiO 2 thin films prepared at 300 deg. C, which correlated to the best crystallinity of the films, as evidenced from X-ray diffraction. In addition, a transparent and conductive anatase TiO 2 thin film with a resistivity of 2.6 x 10 -1 Ω cm was prepared at a substrate temperature of 400 deg. C without the introduction of O 2 gas

  19. Simple method for resistance measurements on thin films and bulk of high T_c superconducting materials

    Science.gov (United States)

    Alzetta, G.; Arimondo, E.; Celli, R. M.; Fuso, F.

    1994-08-01

    Two experimental techniques for measuring resistivity behaviour of high T_c ceramic superconductors in bulk or thin films are described. Particular attention has been given to the development of a four point contact system, easy to use for reliable resistance measurements under repeated, wide thermal cycles. On expose deux méthodes de mesure de la résistivité des supraconducteurs HTc en forme de couches minces déposées sur un substrat ou des céramiques frittées. Le dispositif de mesure, qui a été réalisé avec quatre contacts élastiques, permet d'obtenir des résultats reproductibles dans de très larges intervalles de température.

  20. Preparation and characterisation of Al-doped Zn O thin films

    International Nuclear Information System (INIS)

    Saad, M.; Kassis, A.; Nounou, F.

    2010-12-01

    Al-doped Zn O thin films were prepared using RF magnetron sputtering under several preparation conditions (deposition pressure, RF power, substrate temperature). The films were optically and electrically characterized by measuring their transmission and resistance. Furthermore, x-ray diffraction spectroscopy was used in order to study the structural properties of these films. As a result of this study, the preparation conditions suitable for the highly conductive part of the window layer in solar cells were determined. (author)

  1. Thin film diamond microstructure applications

    Science.gov (United States)

    Roppel, T.; Ellis, C.; Ramesham, R.; Jaworske, D.; Baginski, M. E.; Lee, S. Y.

    1991-01-01

    Selective deposition and abrasion, as well as etching in atomic oxygen or reduced-pressure air, have been used to prepare patterned polycrystalline diamond films which, on further processing by anisotropic Si etching, yield the microstructures of such devices as flow sensors and accelerometers. Both types of sensor have been experimentally tested in the respective functions of hot-wire anemometer and both single- and double-hinged accelerometer.

  2. Recovery of oscillatory magneto-resistance in phase separated La0.3Pr0.4Ca0.3MnO3 epitaxial thin films

    International Nuclear Information System (INIS)

    Alagoz, H. S.; Jeon, J.; Mahmud, S. T.; Saber, M. M.; Chow, K. H.; Jung, J.; Prasad, B.; Egilmez, M.

    2013-01-01

    In-plane angular dependent magneto-resistance has been studied in La 0.3 Pr 0.4 Ca 0.3 MnO 3 (LPCMO) manganite thin films deposited on the (100) oriented NdGaO 3 , and (001) oriented SrTiO 3 and LaAlO 3 substrates. At temperatures where the electronic phase separation is the strongest, a metastable irreversible state exists in the films whose resistivity ρ attains a large time dependent value. The ρ decreases sharply with an increasing angle θ between the magnetic field and the current, and does not display an expected oscillatory cos 2 θ/sin 2 θ dependence for all films. The regular oscillations are recovered during repetitive sweeping of θ between 0° and 180°. We discuss possible factors that could produce these unusual changes in the resistivity

  3. Direct-current substrate bias effects on amorphous silicon sputter-deposited films for thin film transistor fabrication

    International Nuclear Information System (INIS)

    Jun, Seung-Ik; Rack, Philip D.; McKnight, Timothy E.; Melechko, Anatoli V.; Simpson, Michael L.

    2005-01-01

    The effect that direct current (dc) substrate bias has on radio frequency-sputter-deposited amorphous silicon (a-Si) films has been investigated. The substrate bias produces a denser a-Si film with fewer defects compared to unbiased films. The reduced number of defects results in a higher resistivity because defect-mediated conduction paths are reduced. Thin film transistors (TFTs) that were completely sputter deposited were fabricated and characterized. The TFT with the biased a-Si film showed lower leakage (off-state) current, higher on/off current ratio, and higher transconductance (field effect mobility) than the TFT with the unbiased a-Si film

  4. Prediction of crack density and electrical resistance changes in indium tin oxide/polymer thin films under tensile loading

    KAUST Repository

    Mora Cordova, Angel

    2014-06-11

    We present unified predictions for the crack onset strain, evolution of crack density, and changes in electrical resistance in indium tin oxide/polymer thin films under tensile loading. We propose a damage mechanics model to quantify and predict such changes as an alternative to fracture mechanics formulations. Our predictions are obtained by assuming that there are no flaws at the onset of loading as opposed to the assumptions of fracture mechanics approaches. We calibrate the crack onset strain and the damage model based on experimental data reported in the literature. We predict crack density and changes in electrical resistance as a function of the damage induced in the films. We implement our model in the commercial finite element software ABAQUS using a user subroutine UMAT. We obtain fair to good agreement with experiments. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  5. Determination of diffusion coefficients in polypyrrole thin films using a current pulse relaxation method

    Science.gov (United States)

    Penner, Reginald M.; Vandyke, Leon S.; Martin, Charles R.

    1987-01-01

    The current pulse E sub oc relaxation method and its application to the determination of diffusion coefficients in electrochemically synthesized polypyrrole thin films is described. Diffusion coefficients for such films in Et4NBF4 and MeCN are determined for a series of submicron film thicknesses. Measurement of the double-layer capacitance, C sub dl, and the resistance, R sub u, of polypyrrole thin films as a function of potential obtained with the galvanostatic pulse method is reported. Measurements of the electrolyte concentration in reduced polypyrrole films are also presented to aid in the interpretation of the data.

  6. Self-Limited Growth in Pentacene Thin Films.

    Science.gov (United States)

    Pachmajer, Stefan; Jones, Andrew O F; Truger, Magdalena; Röthel, Christian; Salzmann, Ingo; Werzer, Oliver; Resel, Roland

    2017-04-05

    Pentacene is one of the most studied organic semiconducting materials. While many aspects of the film formation have already been identified in very thin films, this study provides new insight into the transition from the metastable thin-film phase to bulk phase polymorphs. This study focuses on the growth behavior of pentacene within thin films as a function of film thickness ranging from 20 to 300 nm. By employing various X-ray diffraction methods, combined with supporting atomic force microscopy investigations, one crystalline orientation for the thin-film phase is observed, while three differently tilted bulk phase orientations are found. First, bulk phase crystallites grow with their 00L planes parallel to the substrate surface; second, however, crystallites tilted by 0.75° with respect to the substrate are found, which clearly dominate the former in ratio; third, a different bulk phase polymorph with crystallites tilted by 21° is found. The transition from the thin-film phase to the bulk phase is rationalized by the nucleation of the latter at crystal facets of the thin-film-phase crystallites. This leads to a self-limiting growth of the thin-film phase and explains the thickness-dependent phase behavior observed in pentacene thin films, showing that a large amount of material is present in the bulk phase much earlier during the film growth than previously thought.

  7. Transparent conductive Ta2O5-codoped ITO thin films prepared by different heating process

    International Nuclear Information System (INIS)

    Zhang, B.; Dong, X.P.; Wu, J.S.; Xu, X.F.

    2008-01-01

    Tantalum-doped indium tin oxide thin films were deposited by a cosputtering technique with an ITO target and a Ta 2 O 5 target. The variations of microstructure, electrical and optical properties with substrate temperature and annealing temperature were investigated in some detail. Ta-doped ITO thin films showed better crystalline structure with different prominent plane orientation by different heating process. ITO:Ta thin films deposited at room temperature showed better optical and electrical properties. Increasing substrate temperature and reasonable annealing temperature could remarkably improve the optical and electrical properties of the films. The variation of carrier concentration had an important influence on near-IR reflection, near-UV absorption and optical bandgap. ITO:Ta thin films showed wider optical bandgap. ITO:Ta thin films under the optimum parameters had a sheet resistance of 10-20 and ohm;/sq and a transmittance of 85% with an optical bandgap of above 4.0 eV. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Crystallization kinetics of amorphous aluminum-tungsten thin films

    Energy Technology Data Exchange (ETDEWEB)

    Car, T.; Radic, N. [Rugjer Boskovic Inst., Zagreb (Croatia). Div. of Mater. Sci.; Ivkov, J. [Institute of Physics, Bijenicka 46, P.O.B. 304, HR-10000 Zagreb (Croatia); Babic, E.; Tonejc, A. [Faculty of Sciences, Physics Department, Bijenicka 32, P.O.B. 162, HR-10000 Zagreb (Croatia)

    1999-01-01

    Crystallization kinetics of the amorphous Al-W thin films under non-isothermal conditions was examined by continuous in situ electrical resistance measurements in vacuum. The estimated crystallization temperature of amorphous films in the composition series of the Al{sub 82}W{sub 18} to Al{sub 62}W{sub 38} compounds ranged from 800 K to 920 K. The activation energy for the crystallization and the Avrami exponent were determined. The results indicated that the crystallization mechanism in films with higher tungsten content was a diffusion-controlled process, whereas in films with the composition similar to the stoichiometric compound (Al{sub 4}W), the interface-controlled crystallization probably occurred. (orig.) With 4 figs., 1 tab., 26 refs.

  9. Silane effects on the surface morphology and abrasion resistance of transparent SiO2/UV-curable resin nano-composites

    International Nuclear Information System (INIS)

    Hsiang, Hsing-I.; Chang, Yu-Lun; Chen, Chi-Yu; Yen, Fu-Su

    2011-01-01

    Transparent ultraviolet curable nano-composite coatings consisting of nano-sized SiO 2 and acrylate resin have been developed to improve the abrasion resistance of organic polymers. The nano-sized SiO 2 particles were surface-modified using various amounts of 3-methacryloxypropyltrimethoxysilane. The 3-methacryloxypropyltrimethoxysilane concentration effects on the surface morphology and abrasion resistance of the transparent SiO 2 /ultraviolet-curable resin nano-composites were investigated using scanning electron microscopy, atomic force microscopy, and ultraviolet-visible spectrophotometer. The results showed that as the 3-methacryloxypropyltrimethoxysilane/SiO 2 weight ratio increased from 0.2 to 0.6, the dispersion, compatibility and cross-linking density between the 3-methacryloxypropyltrimethoxysilane-modified SiO 2 particles and acrylate resin were improved, leading to an increase in abrasion resistance. However, as the 3-methacryloxypropyltrimethoxysilane/SiO 2 weight ratio was increased to 1.5, the additional 3-methacryloxypropyltrimethoxysilane may exceed that needed to fill the pores with the probability of SiO 2 nano-particles existing on the coating surface was lower than that for samples with a 3-methacryloxypropyltrimethoxysilane/SiO 2 weight ratio of 0.6. This produced a decrease in abrasion resistance.

  10. Properties of antimony doped ZnO thin films deposited by spray pyrolysis technique

    Energy Technology Data Exchange (ETDEWEB)

    Sadananda Kumar, N., E-mail: sadanthara@gmail.com; Bangera, Kasturi V.; Shivakumar, G. K. [National Institute of Technology Karnataka, Surathkal, Thin Films Laboratory, Department of Physics (India)

    2015-07-15

    Antimony (Sb) doped zinc oxide (ZnO) thin films were deposited on the glass substrate at 450°C using spray pyrolysis technique. Effect of Sb doping on surface morphology structural, optical and electrical properties were studied. X-ray diffraction (XRD) analysis showed that both the undoped and doped ZnO thin films are polycrystalline in nature with (101) preferred orientation. SEM analysis showed a change in surface morphology of Sb doped ZnO thin films. Doping results in a marked increase in conductivity without affecting the transmittance of the films. ZnO films prepared with 3 at % Sb shows the lowest resistivity of 0.185 Ohm cm with a Hall mobility of 54.05 cm{sup 2} V{sup –1} s{sup –1}, and a hole concentration of 6.25 × 10{sup 17} cm{sup –3}.

  11. Optoelectronic properties of cadmium sulfide thin films deposited by thermal evaporation technique

    International Nuclear Information System (INIS)

    Ali, N.; Iqbal, M.A.; Hussain, S.T.; Waris, M.; Munair, S.A.

    2011-01-01

    The substrate temperature in depositions of thin films plays a vital role in the characteristics of deposited films. We studied few characteristics of cadmium sulphide thin film deposited at different temperature (150 deg. C- 300 deg. C) on corning 7059 glass substrate. We measured transmittance, absorbance, band gap and reflectance via UV spectroscopy. It was found that the transmittance for 300 nm to 1100 nm was greater than 80%. The resistivity and mobility was calculated by Vander Pauw method which were 10-80 cm and 2-60 cm/sup 2/V/sup -1/S/sup -1/ respectively. The thermoelectric properties of the film were measured by hot and cold probe method which shows the N-type nature of the film. (author)

  12. Investigations of electrical and optical properties of functional TCO thin films

    Directory of Open Access Journals (Sweden)

    Domaradzki Jarosław

    2015-06-01

    Full Text Available Transparent conducting oxide (TCO films of indium-tin-oxide were evaporated on the surface of silicon wafers after phosphorous diffusion and on the reference glass substrates. The influence of deposition process parameters (electron beam current, oxygen flow and the substrate temperature on optical and electrical properties of evaporated thin films were investigated by means of resistivity measurements and optical spectrophotometry. The performance of prepared thin films was judged by calculated figure of merit and the best result was obtained for the sample deposited on the substrate heated to the 100 °C and then removed from the deposition chamber and annealed in an air for 5 minutes at 400 °C. Refractive index and extinction coefficient were evaluated based on measured transmission spectra and used for designing of antireflection coating for solar cell. The obtained results showed that prepared TCO thin films are promising as a part of counter electrode in crystalline silicon solar cell construction.

  13. Pulsed laser deposition of ITO thin films and their characteristics

    International Nuclear Information System (INIS)

    Zuev, D. A.; Lotin, A. A.; Novodvorsky, O. A.; Lebedev, F. V.; Khramova, O. D.; Petuhov, I. A.; Putilin, Ph. N.; Shatohin, A. N.; Rumyanzeva, M. N.; Gaskov, A. M.

    2012-01-01

    The indium tin oxide (ITO) thin films are grown on quartz glass substrates by the pulsed laser deposition method. The structural, electrical, and optical properties of ITO films are studied as a function of the substrate temperature, the oxygen pressure in the vacuum chamber, and the Sn concentration in the target. The transmittance of grown ITO films in the visible spectral region exceeds 85%. The minimum value of resistivity 1.79 × 10 −4 Ω cm has been achieved in the ITO films with content of Sn 5 at %.

  14. Low temperature ITO thin film deposition on PES substrate using pulse magnetron sputtering

    International Nuclear Information System (INIS)

    Lin, Y.C.; Li, J.Y.; Yen, W.T.

    2008-01-01

    Experiments were conducted using pulse magnetron sputtering (PMS) to deposit transparent conducting indium tin oxide (ITO) thin film onto flexible polyethersulfone (PES) plastic substrates. The thin film microstructure, optoelectronic and residual stress were analyzed using the modulating PMS power, work pressure, pulse frequency, duty cycle and cycle time process parameters. The residual stress of the thin film was determined by scanning electron microscopy (SEM) combined with the Sony equation. The experimental results show that PMS has a lower process temperature, higher deposition rate and lower resistivity compared with the radio frequency process at the same output power. The duty cycle increase produces the optimum optoelectronic characteristics. When the pressure, power, duty cycle and sputter time are increased, the thin film stress will also increase, causing flexural distortion in the PES plastic substrate. When the deposition thickness reaches 1.5 μm, ITO thin film will appear with a distinct split. Under 5 mtorr work pressure, 60 W power, 33 μs duty time and 2 μs pulse reverse time at duty cycle 95%, thin film with an optimized electrical 3.0 x 10 -4 Ω-cm, RMS surface roughness of 0.85 nm and visible region optical transmittance will be achieved with acquisition of over 85%

  15. Temperature dependence of gas sensing behaviour of TiO2 doped PANI composite thin films

    Science.gov (United States)

    Srivastava, Subodh; Sharma, S. S.; Sharma, Preetam; Sharma, Vinay; Rajura, Rajveer Singh; Singh, M.; Vijay, Y. K.

    2014-04-01

    In the present work we have reported the effect of temperature on the gas sensing properties of TiO2 doped PANI composite thin film based chemiresistor type gas sensors for hydrogen gas sensing application. PANI and TiO2 doped PANI composite were synthesized by in situ chemical oxidative polymerization of aniline at low temperature. The electrical properties of these composite thin films were characterized by I-V measurements as function of temperature. The I-V measurement revealed that conductivity of composite thin films increased as the temperature increased. The changes in resistance of the composite thin film sensor were utilized for detection of hydrogen gas. It was observed that at room temperature TiO2 doped PANI composite sensor shows higher response value and showed unstable behavior as the temperature increased. The surface morphology of these composite thin films has also been characterized by scanning electron microscopy (SEM) measurement.

  16. Biocorrosion investigation of two shape memory nickel based alloys: Ni-Mn-Ga and thin film NiTi.

    Science.gov (United States)

    Stepan, L L; Levi, D S; Gans, E; Mohanchandra, K P; Ujihara, M; Carman, G P

    2007-09-01

    Thin film nitinol and single crystal Ni-Mn-Ga represent two new shape memory materials with potential to be used as percutaneously placed implant devices. However, the biocompatibility of these materials has not been adequately assessed. Immersion tests were conducted on both thin film nitinol and single crystal Ni-Mn-Ga in Hank's balanced salt solution at 37 degrees C and pH 7.4. After 12 h, large pits were found on the Ni-Mn-Ga samples while thin film nitinol displayed no signs of corrosion. Further electrochemical tests on thin film nitinol samples revealed breakdown potentials superior to a mechanically polished nitinol disc. These results suggest that passivation or electropolishing of thin film nitinol maybe unnecessary to promote corrosion resistance.

  17. Investigation of the Optoelectronic Properties of Ti-doped Indium Tin Oxide Thin Film

    Directory of Open Access Journals (Sweden)

    Nen-Wen Pu

    2015-09-01

    Full Text Available : In this study, direct-current magnetron sputtering was used to fabricate Ti-doped indium tin oxide (ITO thin films. The sputtering power during the 350-nm-thick thin-film production process was fixed at 100 W with substrate temperatures increasing from room temperature to 500 °C. The Ti-doped ITO thin films exhibited superior thin-film resistivity (1.5 × 10−4 Ω/cm, carrier concentration (4.1 × 1021 cm−3, carrier mobility (10 cm2/Vs, and mean visible-light transmittance (90% at wavelengths of 400–800 nm at a deposition temperature of 400 °C. The superior carrier concentration of the Ti-doped ITO alloys (>1021 cm−3 with a high figure of merit (81.1 × 10−3 Ω−1 demonstrate the pronounced contribution of Ti doping, indicating their high suitability for application in optoelectronic devices.

  18. Textured indium tin oxide thin films by chemical solution deposition and rapid thermal processing

    International Nuclear Information System (INIS)

    Mottern, Matthew L.; Tyholdt, Frode; Ulyashin, Alexander; Helvoort, Antonius T.J. van; Verweij, Henk; Bredesen, Rune

    2007-01-01

    The microstructure of state-of-the-art chemical solution deposited indium tin oxide thin films typically consists of small randomly oriented grains, high porosity and poor homogeneity. The present study demonstrates how the thin film microstructure can be improved significantly by tailoring the precursor solutions and deposition conditions to be kinetically and thermodynamically favorable for generation of homogeneous textured thin films. This is explained by the occurrence of a single heterogeneous nucleation mechanism. The as-deposited thin films, crystallized at 800 deg. C, have a high apparent density, based on a refractive index of ∼ 1.98 determined by single wavelength ellipsometry at 633 nm. The microstructure of the films consists of columnar grains with preferred orientation as determined by X-ray diffraction and transmission electron microscopy. The resistivity, measured by the four point probe method, is ∼ 2 x 10 -3 Ω cm prior to post-deposition treatments

  19. Contact resistance asymmetry of amorphous indium-gallium-zinc-oxide thin-film transistors by scanning Kelvin probe microscopy

    Science.gov (United States)

    Chen-Fei, Wu; Yun-Feng, Chen; Hai, Lu; Xiao-Ming, Huang; Fang-Fang, Ren; Dun-Jun, Chen; Rong, Zhang; You-Dou, Zheng

    2016-05-01

    In this work, a method based on scanning Kelvin probe microscopy is proposed to separately extract source/drain (S/D) series resistance in operating amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors. The asymmetry behavior of S/D contact resistance is deduced and the underlying physics is discussed. The present results suggest that the asymmetry of S/D contact resistance is caused by the difference in bias conditions of the Schottky-like junction at the contact interface induced by the parasitic reaction between contact metal and a-IGZO. The overall contact resistance should be determined by both the bulk channel resistance of the contact region and the interface properties of the metal-semiconductor junction. Project supported by the Key Industrial R&D Program of Jiangsu Province, China (Grant No. BE2015155), the Priority Academic Program Development of Higher Education Institutions of Jiangsu Province, China, and the Fundamental Research Funds for the Central Universities, China (Grant No. 021014380033).

  20. Low resistivity molybdenum thin film towards the back contact of dye ...

    Indian Academy of Sciences (India)

    Back contact; molybdenum; DC sputtering; dye-sensitized solar cell. 1. Introduction ... Structure and operation mechanism of a DSSC. Figure 2. Mo layers were .... to a better efficiency. In this work, the Mo thin films obtained by implying different.

  1. Thin films for precision optics

    International Nuclear Information System (INIS)

    Araujo, J.F.; Maurici, N.; Castro, J.C. de

    1983-01-01

    The technology of producing dielectric and/or metallic thin films for high precision optical components is discussed. Computer programs were developed in order to calculate and register, graphically, reflectance and transmittance spectra of multi-layer films. The technology of vacuum evaporation of several materials was implemented in our thin-films laboratory; various films for optics were then developed. The possibility of first calculate film characteristics and then produce the film is of great advantage since it reduces the time required to produce a new type of film and also reduces the cost of the project. (C.L.B.) [pt

  2. Analysis of Hard Thin Film Coating

    Science.gov (United States)

    Shen, Dashen

    1998-01-01

    MSFC is interested in developing hard thin film coating for bearings. The wearing of the bearing is an important problem for space flight engine. Hard thin film coating can drastically improve the surface of the bearing and improve the wear-endurance of the bearing. However, many fundamental problems in surface physics, plasma deposition, etc, need further research. The approach is using electron cyclotron resonance chemical vapor deposition (ECRCVD) to deposit hard thin film an stainless steel bearing. The thin films in consideration include SiC, SiN and other materials. An ECRCVD deposition system is being assembled at MSFC.

  3. Thin-film solar cell

    NARCIS (Netherlands)

    Metselaar, J.W.; Kuznetsov, V.I.

    1998-01-01

    The invention relates to a thin-film solar cell provided with at least one p-i-n junction comprising at least one p-i junction which is at an angle alpha with that surface of the thin-film solar cell which collects light during operation and at least one i-n junction which is at an angle beta with

  4. Field-tuned superconductor-insulator transitions and Hall resistance in thin polycrystalline MoN films

    Science.gov (United States)

    Makise, Kazumasa; Ichikawa, Fusao; Asano, Takayuki; Shinozaki, Bunju

    2018-02-01

    We report on the superconductor-insulator transitions (SITs) of disordered molybdenum nitride (MoN) thin films on (1 0 0) MgO substrates as a function of the film thickness and magnetic fields. The T c of the superconducting MoN films, which exhibit a sharp superconducting transition, monotonically decreases as the normal state R sq increases with a decreasing film thickness. For several films with different thicknesses, we estimate the critical field H c and the product zν  ≃  0.6 of the dynamical exponent z and the correlation length exponent ν using a finite scaling analysis. The value of this product can be explained by the (2  +  1) XY model. We found that the Hall resistance ΔR xy (H) is maximized when the magnetic field satisfies H HP(T) \\propto |1  -  T/T C0| in the superconducting state and also in the normal states owning to the superconducting fluctuation corresponding to the ghost critical magnetic field. We measured the Hall conductivity δσ xy (H)  =  σ xy (H)  -  σ xyn and fit the Gaussian approximation theory for δσ xy (H) to the experimental data. Agreement between the data and the theory beyond H c suggests the survival of the Cooper pair in the insulating region of the SIT.

  5. Anomalous aging and strain induced time dependent phenomena in ultra-thin La0.65Ca0.35MnO3 films

    International Nuclear Information System (INIS)

    Egilmez, M.; Saber, M.M.; Abdelhadi, M.; Chow, K.H.; Jung, J.

    2011-01-01

    We have shown that ultra-thin La 0.65 Ca 0.35 MnO 3 films exhibit strong metastable behavior. The resistance can vary with time significantly, suggesting that a state of dynamic phase separation exists whereby one phase grows at the expense of another. Physical properties associated with the metastable behavior have been investigated on the films grown on different substrates. We have found that ultra-thin films age much faster than the thicker counterparts and more interestingly the metastability in the resistance of these films enhanced when aged. -- Highlights: → Ultra-thin La 0.67 Ca 0.33 MnO 3 films exhibit metastable behavior. → Physical properties associated with metastable behavior have been investigated. → The metastability in resistance of the films enhanced when films are aged. → Relaxation rates were used as a relative measure the metastability. → The metastable behavior is sensitive to the strain state of the film.

  6. Thin-Film Material Science and Processing | Materials Science | NREL

    Science.gov (United States)

    Thin-Film Material Science and Processing Thin-Film Material Science and Processing Photo of a , a prime example of this research is thin-film photovoltaics (PV). Thin films are important because cadmium telluride thin film, showing from top to bottom: glass, transparent conducting oxide (thin layer

  7. Brownmillerite thin films as fast ion conductors for ultimate-performance resistance switching memory.

    Science.gov (United States)

    Acharya, Susant Kumar; Jo, Janghyun; Raveendra, Nallagatlla Venkata; Dash, Umasankar; Kim, Miyoung; Baik, Hionsuck; Lee, Sangik; Park, Bae Ho; Lee, Jae Sung; Chae, Seung Chul; Hwang, Cheol Seong; Jung, Chang Uk

    2017-07-27

    An oxide-based resistance memory is a leading candidate to replace Si-based flash memory as it meets the emerging specifications for future memory devices. The non-uniformity in the key switching parameters and low endurance in conventional resistance memory devices are preventing its practical application. Here, a novel strategy to overcome the aforementioned challenges has been unveiled by tuning the growth direction of epitaxial brownmillerite SrFeO 2.5 thin films along the SrTiO 3 [111] direction so that the oxygen vacancy channels can connect both the top and bottom electrodes rather directly. The controlled oxygen vacancy channels help reduce the randomness of the conducting filament (CF). The resulting device displayed high endurance over 10 6 cycles, and a short switching time of ∼10 ns. In addition, the device showed very high uniformity in the key switching parameters for device-to-device and within a device. This work demonstrates a feasible example for improving the nanoscale device performance by controlling the atomic structure of a functional oxide layer.

  8. Size and dimensionality effects in superconducting Mo thin films

    International Nuclear Information System (INIS)

    Fabrega, L; Gil, O; Camon, A; Parra-BorderIas, M; Fernandez-MartInez, I; Costa-Kraemer, J L; Briones, F; Sese, J; Gonzalez-Arrabal, R

    2011-01-01

    Molybdenum is a low T c , type I superconductor whose fundamental properties are poorly known. Its importance as an essential constituent of new high performance radiation detectors, the so-called transition edge sensors (TESs) calls for better characterization of this superconductor, especially in thin film form. Here we report on a study of the basic superconducting features of Mo thin films as a function of their thickness. The resistivity is found to rise and the critical temperature decreases on decreasing film thickness, as expected. More relevant, the critical fields along and perpendicular to the film plane are markedly different, thickness dependent and much larger than the thermodynamic critical field of Mo bulk. These results are consistent with a picture of type II 2D superconducting films, and allow estimates of the fundamental superconducting lengths of Mo. The role of morphology in determining the 2D and type II character of the otherwise type I molybdenum is discussed. The possible consequences of this behaviour on the performance of radiation detectors are also addressed.

  9. Nanocrystal thin film fabrication methods and apparatus

    Science.gov (United States)

    Kagan, Cherie R.; Kim, David K.; Choi, Ji-Hyuk; Lai, Yuming

    2018-01-09

    Nanocrystal thin film devices and methods for fabricating nanocrystal thin film devices are disclosed. The nanocrystal thin films are diffused with a dopant such as Indium, Potassium, Tin, etc. to reduce surface states. The thin film devices may be exposed to air during a portion of the fabrication. This enables fabrication of nanocrystal-based devices using a wider range of techniques such as photolithography and photolithographic patterning in an air environment.

  10. Electrical four-point probing of spherical metallic thin films coated onto micron sized polymer particles

    Energy Technology Data Exchange (ETDEWEB)

    Pettersen, Sigurd R., E-mail: sigurd.r.pettersen@ntnu.no, E-mail: jianying.he@ntnu.no; Stokkeland, August Emil; Zhang, Zhiliang; He, Jianying, E-mail: sigurd.r.pettersen@ntnu.no, E-mail: jianying.he@ntnu.no [NTNU Nanomechanical Lab, Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway); Kristiansen, Helge [NTNU Nanomechanical Lab, Department of Structural Engineering, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim (Norway); Conpart AS, Dragonveien 54, NO-2013 Skjetten (Norway); Njagi, John; Goia, Dan V. [Center for Advanced Materials Processing, Clarkson University, Potsdam, New York 13699-5814 (United States); Redford, Keith [Conpart AS, Dragonveien 54, NO-2013 Skjetten (Norway)

    2016-07-25

    Micron-sized metal-coated polymer spheres are frequently used as filler particles in conductive composites for electronic interconnects. However, the intrinsic electrical resistivity of the spherical thin films has not been attainable due to deficiency in methods that eliminate the effect of contact resistance. In this work, a four-point probing method using vacuum compatible piezo-actuated micro robots was developed to directly investigate the electric properties of individual silver-coated spheres under real-time observation in a scanning electron microscope. Poly(methyl methacrylate) spheres with a diameter of 30 μm and four different film thicknesses (270 nm, 150 nm, 100 nm, and 60 nm) were investigated. By multiplying the experimental results with geometrical correction factors obtained using finite element models, the resistivities of the thin films were estimated for the four thicknesses. These were higher than the resistivity of bulk silver.

  11. Study of the oxidation resistance of ZrxNand ZrxSi1-xN thin films deposited by reactive magnetron sputtering; Estudo da resistencia a oxidacao de filmes finos de ZrxN e ZrxSi1-xN depositados por magnetron sputtering reativo

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, D.R.; Freitas, F.G.R.; Felix, L.C.; Carvalho, R.G.; Fontes Junior, A.S.; Tentardini, E.K., E-mail: daniel.angel0275@gmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Ciencia e Engenharia de Materiais; Silva Junior, H. da [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil)

    2016-07-01

    The objective of this work is to evaluate the oxidation resistance on pure zirconium nitride thin films and with silicon addition (ZrN and ZrSiN respectively). The thin films deposition were performed using reactive magnetron sputtering. The coatings were characterized by Rutherford Backscattering Spectroscopy (RBS), grazing angle X ray diffraction (GAXRD), scanning electronic microscopy (SEM-FEG) and oxidation tests starting from 500°C to 700°C. This study evaluated thin films with silicon content up to 14,9 at.%. GAXRD results showed only ZrN characteristics peaks, which allow the inference that Si3N4 has an amorphous structure. Oxidation tests demonstrate that the film with highest silicon content shows an increase of 200°C in oxidation temperature when compared with ZrN pure thin film. (author)

  12. Highly transparent and conductive thin films fabricated with nano-silver/double-walled carbon nanotube composites.

    Science.gov (United States)

    Lee, Shie-Heng; Teng, Chih-Chun; Ma, Chen-Chi M; Wang, Ikai

    2011-12-01

    This study develops a technique for enhancing the electrical conductivity and optical transmittance of transparent double-walled carbon nanotube (DWNT) film. Silver nanoparticles were modified with a NH(2)(CH(2))(2)SH self-assembled monolayer terminated by amino groups and subsequent surface condensation that reacted with functionalized DWNTs. Ag nanoparticles were grafted on the surface of the DWNTs. The low sheet resistance of the resulting thin conductive film on a polyethylene terephthalate (PET) substrate was due to the increased contact areas between DWNTs and work function by grafting Ag nanoparticles on the DWNT surfaces. Increasing the contact area between DWNTs and work function improved the conductivity of the DWNT-Ag thin films. The prepared DWNT-Ag thin films had a sheet resistance of 53.4 Ω/sq with 90.5% optical transmittance at a 550 nm wavelength. After treatment with HNO(3) and annealing at 150 °C for 30 min, a lower sheet resistance of 45.8 Ω/sq and a higher transmittance of 90.4% could be attained. The value of the DC conductivity to optical conductivity (σ(DC)/σ(OP)) ratio is 121.3. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. A simple visible light photo-assisted method for assembling and curing multilayer GO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro da Silva, Mauro Francisco, E-mail: mfps@usp.br [Escola Politécnica da Universidade de São Paulo, Departamento de Engenharia Metalúrgica e de Materiais, PMT-EPUSP e Departamento de Engenharia de Sistemas Eletrônicos, PSI-EPUSP, Av. Professor Mello Moraes, n° 2463, Cidade Universitária, CEP 05508-030, São Paulo, SP (Brazil); Pontifícia Universidade de São Paulo, Faculdade de Ciências Exatas e Tecnologia, Rua Marquês de Paranaguá, 111, CEP 01303-050, São Paulo, SP (Brazil); Oliveira, Débora Rose de [Instituto de Criminalística da Secretaria de Segurança do Estado de São Paulo, Núcleo de Química, Rua Moncorvo Filho, CEP 05507-060, São Paulo, SP (Brazil); Pontifícia Universidade de São Paulo, Faculdade de Ciências Exatas e Tecnologia, Rua Marquês de Paranaguá, 111, CEP 01303-050, São Paulo, SP (Brazil); and others

    2015-09-01

    A simple and efficient method for deposition of reduced graphene oxide (RGO) thin films onto arbitrary substrates is described. The present protocol consists in the application of radial compression to a thin layer of graphene oxide (GO) formed at the air–liquid interface of an ammoniacal dispersion of graphene oxide by continuous irradiation with visible light, that drives both the formation and curing of the film. Both infrared and near infrared luminescence spectroscopies were used for the proposition of a chemical mechanism in which the in situ singlet oxygen Δ{sup 1}O{sub 2}, generated by the photosensitization of molecular oxygen to visible light, initiates the formation and curing of the film. The GO and RGO films display Raman spectral signatures typical of graphene – based materials, with thickness of ca. 20 nm as evaluated by atomic force microscopy. The deposited films exhibited good transparency to visible light (max. 85%; 550 ± 2 nm), electrical resistivity equals to 14 ± 0.02 Ω m, sheet resistance equals to 5 kΩ sq{sup −1} with associated charge carrier mobility of 200 cm{sup 2}/V s. - Highlights: • Visible light photochemical assembly of self-supported graphene oxide thin films. • Graphene oxide photosensitizer for in situ production of singlet oxygen Δ{sup 1}O{sub 2}. • Δ{sup 1}O{sub 2}, as initiator of formation and curing of graphene oxide thin film. • Deposition of colloidal graphene oxide thin film by radial compression. • Deposition of graphene oxide thin film in arbitrary solid substrate.

  14. Fracture resistance of dental nickel-titanium rotary instruments with novel surface treatment: Thin film metallic glass coating.

    Science.gov (United States)

    Chi, Chih-Wen; Deng, Yu-Lun; Lee, Jyh-Wei; Lin, Chun-Pin

    2017-05-01

    Dental nickel-titanium (NiTi) rotary instruments are widely used in endodontic therapy because they are efficient with a higher success rate. However, an unpredictable fracture of instruments may happen due to the surface characteristics of imperfection (or irregularity). This study assessed whether a novel surface treatment could increase fatigue fracture resistance of dental NiTi rotary instruments. A 200- or 500-nm thick Ti-zirconium-boron (Ti-Zr-B) thin film metallic glass was deposited on ProTaper Universal F2 files using a physical vapor deposition process. The characteristics of coating were analyzed by scanning electron microscopy, transmission electron microscopy, and X-ray diffractometry. In cyclic fatigue tests, the files were performed in a simulated root canal (radius=5 mm, angulation=60°) under a rotating speed of 300rpm. The fatigue fractured cross sections of the files were analyzed with their fractographic performances through scanning electron microscopy images. The amorphous structure of the Ti-Zr-B coating was confirmed by transmission electron microscopy and X-ray diffractometry. The surface of treated files presented smooth morphologies without grinding irregularity. For the 200- and 500-nm surface treatment groups, the coated files exhibited higher resistance of cyclic fatigue than untreated files. In fractographic analysis, treated files showed significantly larger crack-initiation zone; however, no significant differences in the areas of fatigue propagation and catastrophic fracture were found compared to untreated files. The novel surface treatment of Ti-Zr-B thin film metallic glass on dental NiTi rotary files can effectively improve the fatigue fracture resistance by offering a smooth coated surface with amorphous microstructure. Copyright © 2016. Published by Elsevier B.V.

  15. Influence of various thickness metallic interlayers on opto-electric and mechanical properties of AZO thin films on PET substrates

    Science.gov (United States)

    Chang, R. C.; Li, T. C.; Lin, C. W.

    2012-02-01

    Various thickness metallic interlayers to improve the opto-electric and mechanical properties of aluminum-doped zinc oxide (AZO) thin films deposited on flexible polyethylene terephtalate (PET) substrates are studied. The effects of the interlayers on the resistance and transmittance of the AZO thin films are discussed. The result shows that the metallic interlayers effectively improve the electric resistance but reduce the optical transmittance of the AZO thin films. These phenomena become more obvious as the interlayer thickness increases. However, the AZO with an aluminum interlayer still behaves an acceptable transmittance. Moreover, mechanical tests indicate that the aluminum interlayer increases the hardness and modulus, and reduce the residual stress of the AZO thin films. In contrast, the silver and copper interlayers decrease the AZO's mechanical properties. Comparing to those without any interlayer, the results show that the best interlayer is the 6 nm thick aluminum film.

  16. Characteristics of sputtered Al-doped ZnO films for transparent electrodes of organic thin-film transistor

    International Nuclear Information System (INIS)

    Park, Yong Seob; Kim, Han-Ki

    2011-01-01

    Aluminum-doped ZnO (AZO) thin-films were deposited with various RF powers at room temperature by radio frequency (RF) magnetron sputtering method. The electrical properties of the AZO film were improved with the increasing RF power. These results can be explained by the improvement of the crystallinity in the AZO film. We fabricated the organic thin-film transistor (OTFT) of the bottom gate structure using pentacene active and poly-4-vinyl phenol gate dielectric layers on the indium tin oxide gate electrode, and estimated the device properties of the OTFTs including drain current-drain voltage (I D -V D ), drain current-gate voltage (I D -V G ), threshold voltage (V T ), on/off ratio and field effect mobility. The AZO film that grown at 160 W RF power exhibited low resistivity (1.54 x 10 -3 Ω.cm), high crystallinity and uniform surface morphology. The pentacene thin-film transistor using the AZO film that's fabricated at 160 W RF power exhibited good device performance such as the mobility of 0.94 cm 2 /V s and the on/off ratio of ∼ 10 5 . Consequently, the performance of the OTFT such as larger field-effect carrier mobility was determined the conductivity of the AZO source/drain (S/D) electrode. AZO films prepared at room temperature by the sputtering method are suitable for the S/D electrodes in the OTFTs.

  17. High-frequency properties of superconducting Y-Ba-Cu-oxide thin films

    International Nuclear Information System (INIS)

    Ramakrishnan, E.S.; Su, M.; Howng, W.

    1992-01-01

    rf and microwave properties of superconducting YBa 2 Cu 3 O 7-x thin films were measured and analyzed using a coplanar resonator structure. The films were developed by sequential electron-beam evaporation of the metals followed by postanneal processing. dc properties of the films were obtained from resistance-temperature and current-voltage measurements to evaluate the transition temperature and current densities. High-frequency properties were measured from 70 to 10 K and in the frequency range 1--3 GHz to determine the film characteristics as compared to pure copper films on the same substrates

  18. Report D : self-consolidating concrete (SCC) for infrastructure elements - creep, shrinkage and abrasion resistance.

    Science.gov (United States)

    2012-08-01

    Concrete specimens were fabricated for shrinkage, creep, and abrasion resistance : testing. Variations of self-consolidating concrete (SCC) and conventional concrete were : all tested. The results were compared to previous similar testing programs an...

  19. Synthesis and characterization of lead sulphide thin films from ethanolamine (ETA) complexing agent chemical bath

    Science.gov (United States)

    Gashaw Hone, Fekadu; Dejene, F. B.

    2018-02-01

    Polycrystalline lead sulphide (PbS) thin films were grown on glass substrates by chemical bath deposition route using ethanolamine (ETA) as a complexing agent. The effects of ETA molar concentration on the structural, morphological, electrical and optical properties of lead sulphide thin films were thoroughly studied. The XRD analyses revealed that all the deposited thin films were face center cubic crystal structure and their preferred orientations were varied along the (111) and (200) planes. The XRD results further confirmed that ETA concentration had a significant effects on the strain, average crystalline size and dislocation density of the deposited thin films. The SEM studies illustrated the evolution and transformation of surface morphology as ETA molar concentration increased from 0.41 M to 1.64 M. The energy dispersive x-ray analysis was used to verify the compositional elements of the deposited thin films. Optical spectroscopy investigation established that the band gap of the PbS thin films were reduced from 0.98 eV to 0.68 eV as ETA concentration increased. The photoluminescence spectra showed a well defined peak at 428 nm and shoulder around 468 nm for all PbS thin films. The electrical resistivity of the thin films found in the order of 103 Ω cm at room temperature and decreased as the ETA molar concentration was increased.

  20. Effect of doping concentration on the conductivity and optical properties of p-type ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Pathak, Trilok Kumar [Semiconductor Research Lab, Department of Physics, Gurukula Kangri University, Haridwar (India); Kumar, Vinod, E-mail: vinod.phy@gmail.com [Department of Physics, University of the Free State, Bloemfontein (South Africa); Swart, H.C., E-mail: swarthc@ufs.ac.za [Department of Physics, University of the Free State, Bloemfontein (South Africa); Purohit, L.P., E-mail: proflppurohitphys@gmail.com [Semiconductor Research Lab, Department of Physics, Gurukula Kangri University, Haridwar (India)

    2016-01-01

    Nitrogen doped ZnO (NZO) thin films were synthesized on glass substrates by the sol–gel and spin coating method. Zinc acetate dihydrates and ammonium acetate were used as precursors for zinc and nitrogen, respectively. X-ray diffraction study showed that the thin films have a hexagonal wurtzite structure corresponding (002) peak for undoped and doped ZnO thin films. The transmittance of the films was above 80% and the band gap of the film varies from 3.21±0.03 eV for undoped and doped ZnO. The minimum resistivity of NZO thin films was obtained as 0.473 Ω cm for the 4 at% of nitrogen (N) doping with a mobility of 1.995 cm{sup 2}/V s. The NZO thin films showed p-type conductivity at 2 and 3 at% of N doping. The AC conductivity measurements that were carried out in the frequency range 10 kHz to 0.1 MHz showed localized conduction in the NZO thin films. These highly transparent ZnO films can be used as a possible window layer in solar cells.

  1. The influence of sequence of precursor films on CZTSe thin films prepared by ion-beam sputtering deposition

    Science.gov (United States)

    Zhao, Jun; Liang, Guangxing; Zeng, Yang; Fan, Ping; Hu, Juguang; Luo, Jingting; Zhang, Dongping

    2017-02-01

    The CuZnSn (CZT) precursor thin films are grown by ion-beam sputtering Cu, Zn, Sn targets with different orders and then sputtering Se target to fabricate Cu2ZnSnSe4 (CZTSe) absorber thin films on molybdenum substrates. They are annealed in the same vacuum chamber at 400 °C. The characterization methods of CZTSe thin films include X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray photoelectron spectra (XPS) in order to study the crystallographic properties, composition, surface morphology, electrical properties and so on. The results display that the CZTSe thin films got the strongest diffraction peak intensity and were with good crystalline quality and its morphology appeared smooth and compact with a sequence of Cu/Zn/Sn/Se, which reveals that the expected states for CZTSe are Cu1+, Zn2+, Sn4+, Se2+. With the good crystalline quality and close to ideal stoichiometric ratio the resistivity of the CZTSe film with the sequence of Cu/Zn/Sn/Se is lower, whose optical band gap is about 1.50 eV. Project supported by the National Natural Science Foundation of China (No. 61404086), the Basical Research Program of Shenzhen (Nos. JCYJ20150324140036866, JCYJ20150324141711581), and the Natural Science Foundation of SZU (No. 2014017).

  2. Multi-Material Front Contact for 19% Thin Film Solar Cells

    Directory of Open Access Journals (Sweden)

    Joop van Deelen

    2016-02-01

    Full Text Available The trade-off between transmittance and conductivity of the front contact material poses a bottleneck for thin film solar panels. Normally, the front contact material is a metal oxide and the optimal cell configuration and panel efficiency were determined for various band gap materials, representing Cu(In,GaSe2 (CIGS, CdTe and high band gap perovskites. Supplementing the metal oxide with a metallic copper grid improves the performance of the front contact and aims to increase the efficiency. Various front contact designs with and without a metallic finger grid were calculated with a variation of the transparent conductive oxide (TCO sheet resistance, scribing area, cell length, and finger dimensions. In addition, the contact resistance and illumination power were also assessed and the optimal thin film solar panel design was determined. Adding a metallic finger grid on a TCO gives a higher solar cell efficiency and this also enables longer cell lengths. However, contact resistance between the metal and the TCO material can reduce the efficiency benefit somewhat.

  3. Silicon-based thin films as bottom electrodes in chalcogenide nonvolatile memories

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung-Yun [IT Convergence and Components Laboratory, Electronics and Telecommunications Research Institute (ETRI), Yuseong-gu, Daejeon 305-350 (Korea, Republic of)], E-mail: seungyun@etri.re.kr; Yoon, Sung-Min; Choi, Kyu-Jeong; Lee, Nam-Yeal; Park, Young-Sam; Ryu, Sang-Ouk; Yu, Byoung-Gon; Kim, Sang-Hoon; Lee, Sang-Heung [IT Convergence and Components Laboratory, Electronics and Telecommunications Research Institute (ETRI), Yuseong-gu, Daejeon 305-350 (Korea, Republic of)

    2007-10-31

    The effect of the electrical resistivity of a silicon-germanium (SiGe) thin film on the phase transition in a GeSbTe (GST) chalcogenide alloy and the manufacturing aspect of the fabrication process of a chalcogenide memory device employing the SiGe film as bottom electrodes were investigated. While p-type SiGe bottom electrodes were formed using in situ doping techniques, n-type ones could be made in a different manner where phosphorus atoms diffused from highly doped silicon underlayers to undoped SiGe films. The p-n heterojunction did not form between the p-type GST and n-type SiGe layers, and the semiconduction type of the SiGe alloys did not influence the memory device switching. It was confirmed that an optimum resistivity value existed for memory operation in spite of proportionality of Joule heating to electrical resistivity. The very high resistivity of the SiGe film had no effect on the reduction of reset current, which might result from the resistance decrease of the SiGe alloy at high temperatures.

  4. LPG ammonia and nitrogen dioxide gas sensing properties of nanostructured polypyrrole thin film

    Science.gov (United States)

    Bagul, Sagar B.; Upadhye, Deepak S.; Sharma, Ramphal

    2016-05-01

    Nanostructured Polypyrrole thin film was synthesized by easy and economic chemical oxidative polymerization technique on glass at room temperature. The prepared thin film of Polypyrrole was characterized by optical absorbance study by UV-visible spectroscopy and electrical study by I-V measurement system. The optical absorbance spectrum of Polypyrrole shows two fundamental peaks in region of 420 and 890 nm, which confirms the formation of Polypyrrole on glass substrate. The I-V graph of nanostructured Polypyrrole represents the Ohmic nature. Furthermore, the thin film of Polypyrrole was investigated by Scanning electron microscopy for surface morphology study. The SEM micrograph represents spherical nanostructured morphology of Polypyrrole on glass substrate. In order to investigate gas sensing properties, 100 ppm of LPG, Ammonia and Nitrogen Dioxide were injected in the gas chamber and magnitude of resistance has been recorded as a function of time in second. It was observed that nanostructured Polypyrrole thin film shows good sensing behavior at room temperature.

  5. LPG ammonia and nitrogen dioxide gas sensing properties of nanostructured polypyrrole thin film

    Energy Technology Data Exchange (ETDEWEB)

    Bagul, Sagar B., E-mail: nano.sbbagul@gmail.com; Upadhye, Deepak S.; Sharma, Ramphal, E-mail: rps.phy@gmail.com [Thin Film and Nanotechnology Laboratory, Department of Nanotechnology, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad (India)

    2016-05-06

    Nanostructured Polypyrrole thin film was synthesized by easy and economic chemical oxidative polymerization technique on glass at room temperature. The prepared thin film of Polypyrrole was characterized by optical absorbance study by UV-visible spectroscopy and electrical study by I-V measurement system. The optical absorbance spectrum of Polypyrrole shows two fundamental peaks in region of 420 and 890 nm, which confirms the formation of Polypyrrole on glass substrate. The I-V graph of nanostructured Polypyrrole represents the Ohmic nature. Furthermore, the thin film of Polypyrrole was investigated by Scanning electron microscopy for surface morphology study. The SEM micrograph represents spherical nanostructured morphology of Polypyrrole on glass substrate. In order to investigate gas sensing properties, 100 ppm of LPG, Ammonia and Nitrogen Dioxide were injected in the gas chamber and magnitude of resistance has been recorded as a function of time in second. It was observed that nanostructured Polypyrrole thin film shows good sensing behavior at room temperature.

  6. The Role of Work Function and Band Gap in Resistive Switching Behaviour of ZnTe Thin Films

    Science.gov (United States)

    Rowtu, Srinu; Sangani, L. D. Varma; Krishna, M. Ghanashyam

    2018-02-01

    Resistive switching behavior by engineering the electrode work function and band gap of ZnTe thin films is demonstrated. The device structures Au/ZnTe/Au, Au/ZnTe/Ag, Al/ZnTe/Ag and Pt/ZnTe/Ag were fabricated. ZnTe was deposited by thermal evaporation and the stoichiometry and band gap were controlled by varying the source-substrate distance. Band gap could be varied between 1.0 eV to approximately 4.0 eV with the larger band gap being attributed to the partial oxidation of ZnTe. The transport characteristics reveal that the low-resistance state is ohmic in nature which makes a transition to Poole-Frenkel defect-mediated conductivity in the high-resistance states. The highest R off-to- R on ratio achieved is 109. Interestingly, depending on stoichiometry, both unipolar and bipolar switching can be realized.

  7. Preparation of anatase TiO{sub 2} thin films by vacuum arc plasma evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Miyata, Toshihiro [Optoelectronic Device System R and D Center, Kanazawa Institute of Technology, 7-1 Ohgigaoka, Nonoichi, Ishikawa 921-8501 (Japan)]. E-mail: tmiyata@neptune.kanazawa-it.ac.jp; Tsukada, Satoshi [Optoelectronic Device System R and D Center, Kanazawa Institute of Technology, 7-1 Ohgigaoka, Nonoichi, Ishikawa 921-8501 (Japan); Minami, Tadatsugu [Optoelectronic Device System R and D Center, Kanazawa Institute of Technology, 7-1 Ohgigaoka, Nonoichi, Ishikawa 921-8501 (Japan)

    2006-02-01

    Anatase titanium dioxide (TiO{sub 2}) thin films with high photocatalytic activity have been prepared with deposition rates as high as 16 nm/min by a newly developed vacuum arc plasma evaporation (VAPE) method using sintered TiO{sub 2} pellets as the source material. Highly transparent TiO{sub 2} thin films prepared at substrate temperatures from room temperature to 400 deg. C exhibited photocatalytic activity, regardless whether oxygen (O{sub 2}) gas was introduced during the VAPE deposition. The highest photocatalytic activity and photo-induced hydrophilicity were obtained in anatase TiO{sub 2} thin films prepared at 300 deg. C, which correlated to the best crystallinity of the films, as evidenced from X-ray diffraction. In addition, a transparent and conductive anatase TiO{sub 2} thin film with a resistivity of 2.6 x 10{sup -1} {omega} cm was prepared at a substrate temperature of 400 deg. C without the introduction of O{sub 2} gas.

  8. In-situ deposition of YBCO high-Tc superconducting thin films by MOCVD and PE-MOCVD

    International Nuclear Information System (INIS)

    Zhao, J.; Noh, D.W.; Chern, C.; Li, Y.Q.; Norris, P.E.; Kear, B.; Gallois, B.

    1991-01-01

    Metal-Organic Chemical Vapor Deposition (MOCVD) offers the advantages of a high degree of compositional control, adaptability for large scale production, and the potential for low temperature fabrication. The capability of operating at high oxygen partial pressure is particularly suitable for in situ formation of high temperature superconducting (HTSC) films. Yttrium barium copper oxide (YBCO) thin films having a sharp zero-resistance transition with T(sub c) greater than 90 K and J(sub c) of approximately 10(exp 4) A on YSZ have been prepared, in situ, at a substrate temperature of about 800 C. Moreover, the ability to form oxide films at low temperature is very desirable for device applications of HTSC materials. Such a process would permit the deposition of high quality HTSC films with a smooth surface on a variety of substrates. Highly c-axis oriented, dense, scratch resistant, superconducting YBCO thin films with mirror-like surfaces have been prepared, in situ, at a reduced substrate temperature as low as 570 C by a remote microwave-plasma enhanced metal-organic chemical vapor deposition (PE-MOCVD) process. Nitrous oxide was used as a reactant gas to generate active oxidizing species. This process, for the first time, allows the formation of YBCO thin films with the orthorhombic superconducting phase in the as-deposited state. The as-deposited films grown by PE-MOCVD show attainment of zero resistance at 72 K with a transition width of about 5 K. MOCVD was carried out in a commercial production scale reactor with the capability of uniform deposition over 100 sq cm per growth run. Preliminary results indicate that PE-MOCVD is a very attractive thin film deposition process for superconducting device technology

  9. Growth of TiO2 Thin Film on Various Substrates using RF Magnetron Sputtering

    International Nuclear Information System (INIS)

    Ali, Riyaz Ahmad Mohamed; Nayan, Nafarizal

    2011-01-01

    The conductivity of Titanium Dioxide (TiO 2 ) thin film fabricated using Radio Frequency (RF) Magnetron Sputtering on Silicon (Si), Indium doped--Tin Oxide (ITO) and microscope glass (M) substrates is presented in this paper. The dependant of thin film thickness and type of substrate been discussed. TiO 2 was deposited using Ti target in Ar+O 2 (45:10) mixture at 250 W for 45, 60, 75, 90, 105 and 120 minute. Resultant thickness varies from 295 nm to 724 nm with deposition rate 6.4 nm/min. On the other hand, resistivity, Rs value for ITO substrate is between 5.72x10 -7 to 1.54x10 -6 Ω.m, Si substrate range is between 3.52x10 -6 to 1.76x10 -5 Ω.m and M substrate range is between 99 to 332 Ω.m. The value of resistivity increases with the thickness of the thin film.

  10. Fabrication and characteristics of magnetic field sensors based on nano-polysilicon thin-film transistors

    International Nuclear Information System (INIS)

    Zhao Xiaofeng; Wen Dianzhong; Zhuang Cuicui; Cao Jingya; Wang Zhiqiang

    2013-01-01

    A magnetic field sensor based on nano-polysilicon thin films transistors (TFTs) with Hall probes is proposed. The magnetic field sensors are fabricated on 〈100〉 orientation high resistivity (ρ > 500 Ω·cm) silicon substrates by using CMOS technology, which adopt nano-polysilicon thin films with thicknesses of 90 nm and heterojunction interfaces between the nano-polysilicon thin films and the high resistivity silicon substrates as the sensing layers. The experimental results show that when V DS = 5.0 V, the magnetic sensitivities of magnetic field sensors based on nano-polysilicon TFTs with length—width ratios of 160 μm/80 μm, 320 μm/80 μm and 480 μm/80 μm are 78 mV/T, 55 mV/T and 34 mV/T, respectively. Under the same conditions, the magnetic sensitivity of the obtained magnetic field sensor is significantly improved in comparison with a Hall magnetic field sensor adopting silicon as the sensing layers. (semiconductor technology)

  11. Characterizations of photoconductivity of graphene oxide thin films

    Directory of Open Access Journals (Sweden)

    Shiang-Kuo Chang-Jian

    2012-06-01

    Full Text Available Characterizations of photoresponse of a graphene oxide (GO thin film to a near infrared laser light were studied. Results showed the photocurrent in the GO thin film was cathodic, always flowing in an opposite direction to the initial current generated by the preset bias voltage that shows a fundamental discrepancy from the photocurrent in the reduced graphene oxide thin film. Light illumination on the GO thin film thus results in more free electrons that offset the initial current. By examining GO thin films reduced at different temperatures, the critical temperature for reversing the photocurrent from cathodic to anodic was found around 187°C. The dynamic photoresponse for the GO thin film was further characterized through the response time constants within the laser on and off durations, denoted as τon and τoff, respectively. τon for the GO thin film was comparable to the other carbon-based thin films such as carbon nanotubes and graphenes. τoff was, however, much larger than that of the other's. This discrepancy was attributable to the retardation of exciton recombination rate thanks to the existing oxygen functional groups and defects in the GO thin films.

  12. Characterization of Thin Film Polymers Through Dynamic Mechanical Analysis and Permeation

    Science.gov (United States)

    Herring, Helen

    2003-01-01

    Thin polymer films are being considered, as candidate materials to augment the permeation resistance of cryogenic hydrogen fuel tanks such as would be required for future reusable launch vehicles. To evaluate performance of candidate films after environmental exposure, an experimental study was performed to measure the thermal/mechanical and permeation performance of six, commercial-grade materials. Dynamic storage modulus, as measured by Dynamic Mechanical Analysis, was found over a range of temperatures. Permeability, as measured by helium gas diffusion, was found at room temperature. Test data was correlated with respect to film type and pre-test exposure to moisture, elevated temperature, and cryogenic temperature. Results indicated that the six films were comparable in performance and their resistance to environmental degradation.

  13. Development of natively textured surface hydrogenated Ga-doped ZnO-TCO thin films for solar cells via magnetron sputtering

    International Nuclear Information System (INIS)

    Wang, Fei; Chen, Xin-liang; Geng, Xin-hua; Zhang, De-kun; Wei, Chang-chun; Huang, Qian; Zhang, Xiao-dan; Zhao, Ying

    2012-01-01

    Highlights: ► Natively textured surface hydrogenated gallium-doped zinc oxide (HGZO) thin films have been deposited via magnetron sputtering on glass substrates. ► The directly deposited HGZO thin films present rough crater-type surface morphology. ► Typical HGZO thin film exhibits a high electron mobility of 41.3 cm 2 /V s and a relative low sheet resistance of ∼7.0 Ω. ► These HGZO thin films have high optical transmittances in the visible and near infrared region (∼380–1100 nm). ► A gradient H 2 growth method for fabricating HGZO thin films has been proposed in magnetron sputtering process. - Abstract: The main purposes are to obtain high quality transparent conductive oxide (TCO) based on zinc oxide (ZnO) thin films with high optical transparency in the visible and near infrared spectral range, high electrical conductivity and good light-scattering capability to enhance the path of the light inside the Si-based thin film solar cells. Natively textured surface hydrogenated gallium-doped ZnO (HGZO) thin films have been deposited via pulsed direct current (DC) magnetron sputtering on glass substrates at a substrate temperature of 553 K. These natively textured HGZO thin films exhibit high optical transmittance (over 80%) in the visible and near infrared region (λ = 380–1100 nm) and excellent electrical properties. The optimized HGZO thin film with crater-type textured surface obtained at the hydrogen flow rate of ∼2.0 sccm exhibits a high electron mobility of 41.3 cm 2 /V s and a relatively low sheet resistance of ∼7.0 Ω. The influences of hydrogen flow rates on the surface morphology, electrical and optical properties of HGZO thin films were investigated in detail. In addition, we put forward a method of gradient H 2 growth technique for fabricating HGZO thin films so as to obtain rough surface structure with good light-scattering capability and high electrical conductivity. “Crater-like” surface feature size and optical transmittance

  14. Comparison of the Thermal Degradation of Heavily Nb-Doped and Normal PZT Thin Films.

    Science.gov (United States)

    Yang, Jeong-Suong; Kang, YunSung; Kang, Inyoung; Lim, SeungMo; Shin, Seung-Joo; Lee, JungWon; Hur, Kang Heon

    2017-03-01

    The degradation of niobium-doped lead zirconate titanate (PZT) and two types of PZT thin films were investigated. Undoped PZT, two-step PZT, and heavily Nb-doped PZT (PNZT) around the morphotropic phase boundary were in situ deposited under optimum condition by RF-magnetron sputtering. All 2- [Formula: see text]-thick films had dense perovskite columnar grain structure and self-polarized (100) dominant orientation. PZT thin films were deposited on Pt/TiO x bottom electrode on Si wafer, and PNZT thin film was on Ir/TiW electrode with the help of orientation control. Sputtered PZT films formed on microelectromechanical system (MEMS) gyroscope and the degradation rates were compared at different temperatures. PNZT showed the best resistance to the thermal degradation, followed by two-step PZT. To clarify the effect of oxygen vacancies on the degradation of the film at high temperature, photoluminescence measurement was conducted, which confirmed that oxygen vacancy rate was the lowest in heavy PNZT. Nb-doping PZT thin films suppressed the oxygen deficit and made high imprint with self-polarization. This defect distribution and high internal field allowed PNZT thin film to make the piezoelectric sensors more stable and reliable at high temperature, such as reflow process of MEMS packaging.

  15. Preparation of Zinc Oxide (ZnO) Thin Film as Transparent Conductive Oxide (TCO) from Zinc Complex Compound on Thin Film Solar Cells: A Study of O2 Effect on Annealing Process

    Science.gov (United States)

    Muslih, E. Y.; Kim, K. H.

    2017-07-01

    Zinc oxide (ZnO) thin film as a transparent conductive oxide (TCO) for thin film solar cell application was successfully prepared through two step preparations which consisted of deposition by spin coating at 2000 rpm for 10 second and followed by annealing at 500 °C for 2 hours under O2 and ambient atmosphere. Zinc acetate dehydrate was used as a precursor which dissolved in ethanol and acetone (1:1 mol) mixture in order to make a zinc complex compound. In this work, we reported the O2 effect, reaction mechanism, structure, morphology, optical and electrical properties. ZnO thin film in this work shows a single phase of wurtzite, with n-type semiconductor and has band gap, carrier concentration, mobility, and resistivity as 3.18 eV, 1.21 × 10-19cm3, 11 cm2/Vs, 2.35 × 10-3 Ωcm respectively which is suitable for TCO at thin film solar cell.

  16. Characterization of gadolinium oxide thin films with CF{sub 4} plasma treatment for resistive switching memory applications

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jer-Chyi, E-mail: jcwang@mail.cgu.edu.tw [Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan 333, Tao-Yuan, Taiwan (China); Ye, Yu-Ren [Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan 333, Tao-Yuan, Taiwan (China); Lai, Chao-Sung, E-mail: cslai@mail.cgu.edu.tw [Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan 333, Tao-Yuan, Taiwan (China); Lin, Chih-Ting [Department of Electronic Engineering, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-Shan 333, Tao-Yuan, Taiwan (China); Lu, Hsin-Chun [Department of Chemical and Materials Engineering, Chang Gung University, Kwei-Shan 333, Tao-Yuan, Taiwan (China); Wu, Chih-I [Graduated Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 106, Taiwan (China); Department of Electrical Engineering, National Taiwan University, Taipei 106, Taiwan (China); Wang, Po-Sheng [Graduated Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 106, Taiwan (China)

    2013-07-01

    The effect of the CF{sub 4} plasma treatment on the gadolinium oxide (Gd{sub x}O{sub y}) thin films for the resistive random access memory (RRAM) applications was investigated. The material properties of the fluorine incorporated Gd{sub x}O{sub y} films were analyzed by the X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS) and ultraviolet–visible spectroscopy (UV–VIS). Further, the set and reset voltages of the Pt/Gd{sub x}O{sub y}/W RRAM devices with the CF{sub 4} plasma treatment were effectively reduced to −1.15 and 2.1 V respectively owing to the low Schottky barrier height. The formation of Gd-F bonds can prevent the oxygen atoms from out-diffusing through Pt grain boundaries into the atmosphere, leading to the superior retention characteristics for over 10{sup 4} s. The CF{sub 4} plasma treated Gd{sub x}O{sub y} RRAMs can sustain a resistance ratio of 10{sup 2} for more than 800 times stable set/reset cycling, suitable for future low-voltage and high-performance nonvolatile memory operation.

  17. Development of neutron diffuse scattering analysis code by thin film and multilayer film

    International Nuclear Information System (INIS)

    Soyama, Kazuhiko

    2004-01-01

    To research surface structure of thin film and multilayer film by neutron, a neutron diffuse scattering analysis code using DWBA (Distorted-Wave Bron Approximation) principle was developed. Subjects using this code contain the surface and interface properties of solid/solid, solid/liquid, liquid/liquid and gas/liquid, and metal, magnetism and polymer thin film and biomembran. The roughness of surface and interface of substance shows fractal self-similarity and its analytical model is based on DWBA theory by Sinha. The surface and interface properties by diffuse scattering are investigated on the basis of the theoretical model. The calculation values are proved to be agreed with the experimental values. On neutron diffuse scattering by thin film, roughness of surface of thin film, correlation function, neutron propagation by thin film, diffuse scattering by DWBA theory, measurement model, SDIFFF (neutron diffuse scattering analysis program by thin film) and simulation results are explained. On neutron diffuse scattering by multilayer film, roughness of multilayer film, principle of diffuse scattering, measurement method and simulation examples by MDIFF (neutron diffuse scattering analysis program by multilayer film) are explained. (S.Y.)To research surface structure of thin film and multilayer film by neutron, a neutron diffuse scattering analysis code using DWBA (Distorted-Wave Bron Approximation) principle was developed. Subjects using this code contain the surface and interface properties of solid/solid, solid/liquid, liquid/liquid and gas/liquid, and metal, magnetism and polymer thin film and biomembran. The roughness of surface and interface of substance shows fractal self-similarity and its analytical model is based on DWBA theory by Sinha. The surface and interface properties by diffuse scattering are investigated on the basis of the theoretical model. The calculation values are proved to be agreed with the experimental values. On neutron diffuse scattering

  18. Relation of planar Hall and planar Nernst effects in thin film permalloy

    Science.gov (United States)

    Wesenberg, D.; Hojem, A.; Bennet, R. K.; Zink, B. L.

    2018-06-01

    We present measurements of the planar Nernst effect (PNE) and the planar Hall effect (PHE) of nickel-iron (Ni–Fe) alloy thin films. We suspend the thin-film samples, measurement leads, and lithographically-defined heaters and thermometers on silicon-nitride membranes to greatly simplify control and measurement of thermal gradients essential to quantitative determination of magnetothermoelectric effects. Since these thermal isolation structures allow measurements of longitudinal thermopower, or the Seebeck coefficient, and four-wire electrical resistivity of the same thin film, we can quantitatively demonstrate the link between the longitudinal and transverse effects as a function of applied in-plane field and angle. Finite element thermal analysis of this essentially 2D structure allows more confident determination of the thermal gradient, which is reduced from the simplest assumptions due to the particular geometry of the membranes, which are more than 350 μm wide in order to maximize sensitivity to transverse thermoelectric effects. The resulting maximum values of the PNE and PHE coefficients for the Ni–Fe film with 80% Ni we study here are and , respectively. All signals are exclusively symmetry with applied field, ruling out long-distance spin transport effects. We also consider a Mott-like relation between the PNE and PHE, and use both this and the standard Mott relation to determine the energy-derivative of the resistivity at the Fermi energy to be , which is very similar to values for films we previously measured using similar thermal platforms. Finally, using an estimated value for the lead contribution to the longitudinal thermopower, we show that the anisotropic magnetoresistance (AMR) ratio in this Ni–Fe film is two times larger than the magnetothermopower ratio, which is the first evidence of a deviation from strict adherence to the Mott relation between Seebeck coefficient and resistivity.

  19. Properties of thermometric NbSi thin films and application to detection in astrophysics

    Energy Technology Data Exchange (ETDEWEB)

    Marrache-Kikuchi, C.A. [CSNSM, CNRS-IN2P3, Bat 108, 91405 Orsay Campus (France)]. E-mail: kikuchi@csnsm.in2p3.fr; Berge, L. [CSNSM, CNRS-IN2P3, Bat 108, 91405 Orsay Campus (France); Collin, S. [CSNSM, CNRS-IN2P3, Bat 108, 91405 Orsay Campus (France); Dobrea, C. [CSNSM, CNRS-IN2P3, Bat 108, 91405 Orsay Campus (France); Dumoulin, L. [CSNSM, CNRS-IN2P3, Bat 108, 91405 Orsay Campus (France); Juillard, A. [CSNSM, CNRS-IN2P3, Bat 108, 91405 Orsay Campus (France); Marnieros, S. [CSNSM, CNRS-IN2P3, Bat 108, 91405 Orsay Campus (France)

    2006-04-15

    We report the low-temperature study of very thin Nb{sub x}Si{sub 1-x} films that are used in various systems for astrophysical detection with bolometers. We have decreased the thin film thicknesses from 60nm down to 12.5nm and shown that the sensitivity gain due to lowering the heat capacity is not to the detriment of the electron-phonon coupling or to noise characteristics. On the superconducting side, we show that, at small thicknesses, the critical temperature and the normal resistance can be adjusted by tuning the thickness and the composition of the films.

  20. Study on film resistivity of Energy Conversion Components for MEMS Initiating Explosive Device

    Science.gov (United States)

    Ren, Wei; Zhang, Bin; Zhao, Yulong; Chu, Enyi; Yin, Ming; Li, Hui; Wang, Kexuan

    2018-03-01

    Resistivity of Plane-film Energy Conversion Components is a key parameter to influence its resistance and explosive performance, and also it has important relations with the preparation of thin film technology, scale, structure and etc. In order to improve the design of Energy Conversion Components for MEMS Initiating Explosive Device, and reduce the design deviation of Energy Conversion Components in microscale, guarantee the design resistance and ignition performance of MEMS Initiating Explosive Device, this paper theoretically analyzed the influence factors of film resistivity in microscale, through the preparation of Al film and Ni-Cr film at different thickness with micro/nano, then obtain the film resistivity parameter of the typical metal under different thickness, and reveals the effect rule of the scale to the resistivity in microscale, at the same time we obtain the corresponding inflection point data.

  1. Thin film tritium dosimetry

    Science.gov (United States)

    Moran, Paul R.

    1976-01-01

    The present invention provides a method for tritium dosimetry. A dosimeter comprising a thin film of a material having relatively sensitive RITAC-RITAP dosimetry properties is exposed to radiation from tritium, and after the dosimeter has been removed from the source of the radiation, the low energy electron dose deposited in the thin film is determined by radiation-induced, thermally-activated polarization dosimetry techniques.

  2. Assembly of metallic nanoparticle arrays on glass via nanoimprinting and thin-film dewetting

    Directory of Open Access Journals (Sweden)

    Sun-Kyu Lee

    2017-05-01

    Full Text Available We propose a nanofabrication process to generate large-area arrays of noble metal nanoparticles on glass substrates via nanoimprinting and dewetting of metallic thin films. Glass templates were made via pattern transfer from a topographic Si mold to an inorganically cross-linked sol–gel (IGSG resist on glass using a two-layer polydimethylsiloxane (PDMS stamp followed by annealing, which turned the imprinted resist into pure silica. The transparent, topographic glass successfully templated the assembly of Au and Ag nanoparticle arrays via thin-film deposition and dewetting at elevated temperatures. The microstructural and mechanical characteristics that developed during the processes were discussed. The results are promising for low-cost mass fabrication of devices for several photonic applications.

  3. Assembly of metallic nanoparticle arrays on glass via nanoimprinting and thin-film dewetting.

    Science.gov (United States)

    Lee, Sun-Kyu; Hwang, Sori; Kim, Yoon-Kee; Oh, Yong-Jun

    2017-01-01

    We propose a nanofabrication process to generate large-area arrays of noble metal nanoparticles on glass substrates via nanoimprinting and dewetting of metallic thin films. Glass templates were made via pattern transfer from a topographic Si mold to an inorganically cross-linked sol-gel (IGSG) resist on glass using a two-layer polydimethylsiloxane (PDMS) stamp followed by annealing, which turned the imprinted resist into pure silica. The transparent, topographic glass successfully templated the assembly of Au and Ag nanoparticle arrays via thin-film deposition and dewetting at elevated temperatures. The microstructural and mechanical characteristics that developed during the processes were discussed. The results are promising for low-cost mass fabrication of devices for several photonic applications.

  4. Quench and recovery characteristics of Au/YBCO thin film type SFCL

    International Nuclear Information System (INIS)

    Yim, S.-W.; Kim, H.-R.; Hyun, O.-B.; Sim, J.

    2007-01-01

    Although, a superconducting fault current limiter (SFCL) guarantees the fast limiting operation, it usually needs a considerably long time to recover to superconducting state after the quench. Considering the reclosing time in the protection coordination of power systems, the time required for the recovery should be investigated clearly. In this study, the quench and recovery characteristics of Au/YBCO thin films designed as an SFCL element with a bi-spiral pattern were investigated. The quench development of the SFCL was measured by two kinds of methods. Firstly, after applying the fault current of 5.5 cycles, we measured the resistance of the YBCO by a small current flowing through the pattern of Au/YBCO thin film. The temperature variation above the critical temperature, 85 K, was investigated indirectly from the resistance variation. Secondly, in order to measure the temperature from 85 K to 77 K, a meander line shape of Au thin film was evaporated on the back side and used as a temperature detecting sensor. The temperature variations detected by both methods were compared and analyzed. For the investigation of the recovery characteristics, the required time for the recovery of the superconductivity was measured for various magnitude and duration of the applied voltages. In addition, for the purpose of examining the dependence of the line impedance on the recovery time, resistors of various resistances were inserted in the fault current testing circuit and the recovery time was measured and analyzed

  5. Experimental investigation on photoelectric properties of ZAO thin film deposited on flexible substrate by magnetron sputtering

    Science.gov (United States)

    Hao, Ming; Liu, Kun; Liu, Xinghua; Wang, Dongyang; Ba, Dechun; Xie, Yuanhua; Du, Guangyu; Ba, Yaoshuai

    2016-12-01

    Transparent conductive ZAO (Zinc Aluminum Oxide) films on flexible substrates have a great potential for low-cost mass-production solar cells. ZAO thin films were achieved on flexible PET (polyethylene terephthalate) substrates by RF magnetron sputtering technology. The surface morphology and element content, the transmittance and the sheet resistance of the films were measured to determine the optical process parameters. The results show that the ZAO thin film shows the best parameters in terms of photoelectric performance including sputtering power, working pressure, sputtering time, substrate temperature (100 W, 1.5 Pa, 60 min, 125 °C). The sheet resistance of 510 Ω and transmittance in visible region of 92% were obtained after characterization. Surface morphology was uniform and compact with a good crystal grain.

  6. Thin films for emerging applications v.16

    CERN Document Server

    Francombe, Maurice H

    1992-01-01

    Following in the long-standing tradition of excellence established by this serial, this volume provides a focused look at contemporary applications. High Tc superconducting thin films are discussed in terms of ion beam and sputtering deposition, vacuum evaporation, laser ablation, MOCVD, and other deposition processes in addition to their ultimate applications. Detailed treatment is also given to permanent magnet thin films, lateral diffusion and electromigration in metallic thin films, and fracture and cracking phenomena in thin films adhering to high-elongation substrates.

  7. Room temperature deposition of ZnSe thin films by successive ionic layer adsorption and reaction (SILAR) method

    International Nuclear Information System (INIS)

    Kale, R.B.; Lokhande, C.D.

    2004-01-01

    The zinc selenide (ZnSe) thin films are deposited onto glass substrate using relatively simple and inexpensive successive ionic layer adsorption and reaction (SILAR) method. The films are deposited using zinc acetate sodium selenosulphate precursors. The concentration, pH, immersion and rinsing times and number of immersion cycles have been optimized to obtain good quality ZnSe thin films. The X-ray diffraction (XRD) study and scanning electron microscopy (SEM) studies reveals nanocrystalline nature alongwith some amorphous phase present in ZnSe thin films. Energy dispersive X-ray (EDAX) analysis shows that the films are Se deficient. From optical absorption data, the optical band gap 'E g ' for as-deposited thin film was found to be 2.8 eV and electrical resistivity in the order of 10 7 Ω cm

  8. Conformal Thin Film Packaging for SiC Sensor Circuits in Harsh Environments

    Science.gov (United States)

    Scardelletti, Maximilian C.; Karnick, David A.; Ponchak, George E.; Zorman, Christian A.

    2011-01-01

    In this investigation sputtered silicon carbide annealed at 300 C for one hour is used as a conformal thin film package. A RF magnetron sputterer was used to deposit 500 nm silicon carbide films on gold metal structures on alumina wafers. To determine the reliability and resistance to immersion in harsh environments, samples were submerged in gold etchant for 24 hours, in BOE for 24 hours, and in an O2 plasma etch for one hour. The adhesion strength of the thin film was measured by a pull test before and after the chemical immersion, which indicated that the film has an adhesion strength better than 10(exp 8) N/m2; this is similar to the adhesion of the gold layer to the alumina wafer. MIM capacitors are used to determine the dielectric constant, which is dependent on the SiC anneal temperature. Finally, to demonstrate that the SiC, conformal, thin film may be used to package RF circuits and sensors, an LC resonator circuit was fabricated and tested with and without the conformal SiC thin film packaging. The results indicate that the SiC coating adds no appreciable degradation to the circuits RF performance. Index Terms Sputter, silicon carbide, MIM capacitors, LC resonators, gold etchants, BOE, O2 plasma

  9. Interfaces and thin films physics

    International Nuclear Information System (INIS)

    Equer, B.

    1988-01-01

    The 1988 progress report of the Interfaces and Thin Film Physics laboratory (Polytechnic School France) is presented. The research program is focused on the thin films and on the interfaces of the amorphous semiconductor materials: silicon and silicon germanium, silicon-carbon and silicon-nitrogen alloys. In particular, the following topics are discussed: the basic processes and the kinetics of the reactive gas deposition, the amorphous materials manufacturing, the physico-chemical characterization of thin films and interfaces and the electron transport in amorphous semiconductors. The construction and optimization of experimental devices, as well as the activities concerning instrumentation, are also described [fr

  10. Comparison of four-probe thermal and thermoelectric transport measurements of thin films and nanostructures with microfabricated electro-thermal transducers

    Science.gov (United States)

    Kim, Jaehyun; Fleming, Evan; Zhou, Yuanyuan; Shi, Li

    2018-03-01

    Two different four-probe thermal and thermoelectric measurement methods have been reported for measuring the thermal conductivity, Seebeck coefficient, and electrical conductivity of suspended thin films and nanostructures with microfabricated electro-thermal transducers. The thermal contact resistance was extracted from the measured thermoelectric voltage drop at the contacts in the earlier four-probe method based on the assumption of constant thermal and thermoelectric properties along the sample. In comparison, the latter four-probe method can directly obtain the contact thermal resistance together with the intrinsic sample thermal resistance without making this assumption. Here, the measurement theory and data reduction processes of the latter four-probe measurement method are re-examined and improved. The measured thermal conductivity result of this improved method on representative thin film samples are found to agree with those obtained from the earlier four-probe method, which has obtained similar Seebeck coefficient and electrical conductivity as those measured with a different method for a supported thin film. The agreement provides further validation of the latest four-probe thermal transport measurement method of thin films and nanostructures.

  11. Standard Test Method for Abrasive Wear Resistance of Cemented

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This test method covers the determination of abrasive wear resistance of cemented carbides. 1.2 The values stated in inch-pound units are to be regarded as the standard. The SI equivalents of inch-pound units are in parentheses and may be approximate. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  12. Thin film femtosecond laser damage competition

    Science.gov (United States)

    Stolz, Christopher J.; Ristau, Detlev; Turowski, Marcus; Blaschke, Holger

    2009-10-01

    In order to determine the current status of thin film laser resistance within the private, academic, and government sectors, a damage competition was started at the 2008 Boulder Damage Symposium. This damage competition allows a direct comparison of the current state of the art of high laser resistance coatings since they are tested using the same damage test setup and the same protocol. In 2009 a high reflector coating was selected at a wavelength of 786 nm at normal incidence at a pulse length of 180 femtoseconds. A double blind test assured sample and submitter anonymity so only a summary of the results are presented here. In addition to the laser resistance results, details of deposition processes, coating materials and layer count, and spectral results will also be shared.

  13. Buckling of Thin Films in Nano-Scale

    Directory of Open Access Journals (Sweden)

    Li L.A.

    2010-06-01

    Full Text Available Investigation of thin film buckling is important for life prediction of MEMS device which are damaged mainly by the delamination and buckling of thin films. In this paper the mechanical and thermal properties of compressed thin film titanium films with 150 nm thickness deposited on an organic glass substrate under mechanical and thermal loads were measured and characterized. In order to simulate the thin films which subjected to compound loads and the buckle modes the external uniaxial compression and thermal loading were subjected to the specimen by the symmetric loading device and the electrical film in this experiment. The temperature of the thin film deposited on substrate was measured using thermoelectric couple. The range of temperature accords with the temperature range of the MEMS. It is found that the size and number of the delamination and buckling of the film are depended upon the pre-fixed mechanical loading and thermal temperature. The thermal transient conduction and thermal stability of the film and substrate was studied with finite element method.

  14. Fabrication and characterization of NiO thin films prepared by SILAR method

    International Nuclear Information System (INIS)

    Akaltun, Yunus; Çayır, Tuba

    2015-01-01

    Highlights: • NiO thin films have been deposited on glass substrates using SILAR method for the first time. • The electron effective mass, refractive index were calculated by using the energy bandgap values. • The effect of film thickness on the structural, optical and electrical properties were studied. • The bandgap values of the films decreased from 3.71 to 3.67 eV. - Abstract: NiO thin films were synthesised on glass substrates at room temperature using the Successive Ionic Layer Adsorption and Reaction (SILAR) method. The effect of film thickness on the structural, morphological, optical and electrical properties of NiO thin films was investigated. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies showed that all the films exhibit polycrystalline structure are covered well with glass substrates. The crystalline and surface properties of the films improved with increasing film thickness. The energy band gap values were decreased from 3.71 to 3.67 eV depending on the film thickness. The refractive index (n), optical static (ε o ) and high frequency dielectric constant (ε ∞ ) values were calculated by using the energy band gap values as a function of the film thickness. The resistivity of the films varied between 4.1 and 802.1 Ω cm with increasing film thickness at room temperature

  15. Fabrication and characterization of NiO thin films prepared by SILAR method

    Energy Technology Data Exchange (ETDEWEB)

    Akaltun, Yunus [Department of Electrical and Electronic Engineering, Erzincan University, 24100 Erzincan (Turkey); Çayır, Tuba [Department of Biomedical Engineering, Erzincan University, 24100 Erzincan (Turkey)

    2015-03-15

    Highlights: • NiO thin films have been deposited on glass substrates using SILAR method for the first time. • The electron effective mass, refractive index were calculated by using the energy bandgap values. • The effect of film thickness on the structural, optical and electrical properties were studied. • The bandgap values of the films decreased from 3.71 to 3.67 eV. - Abstract: NiO thin films were synthesised on glass substrates at room temperature using the Successive Ionic Layer Adsorption and Reaction (SILAR) method. The effect of film thickness on the structural, morphological, optical and electrical properties of NiO thin films was investigated. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies showed that all the films exhibit polycrystalline structure are covered well with glass substrates. The crystalline and surface properties of the films improved with increasing film thickness. The energy band gap values were decreased from 3.71 to 3.67 eV depending on the film thickness. The refractive index (n), optical static (ε{sub o}) and high frequency dielectric constant (ε{sub ∞}) values were calculated by using the energy band gap values as a function of the film thickness. The resistivity of the films varied between 4.1 and 802.1 Ω cm with increasing film thickness at room temperature.

  16. Pulsed laser deposition of transparent conductive oxide thin films on flexible substrates

    International Nuclear Information System (INIS)

    Socol, G.; Socol, M.; Stefan, N.; Axente, E.; Popescu-Pelin, G.; Craciun, D.; Duta, L.; Mihailescu, C.N.; Mihailescu, I.N.; Stanculescu, A.; Visan, D.; Sava, V.; Galca, A.C.; Luculescu, C.R.; Craciun, V.

    2012-01-01

    Highlights: ► TCO thin films were grown by PLD on PET substrate at low temperature. ► We found that the quality of TCO on PET substrate depends on the target–substrate distance. ► TCO with high transparency (>95%) and reduced electrical resistivity (∼5 × 10 −4 Ω cm) were obtained. ► Optimized TCO films deposited on PET were free of any cracks. - Abstract: The influence of target–substrate distance during pulsed laser deposition of indium zinc oxide (IZO), indium tin oxide (ITO) and aluminium-doped zinc oxide (AZO) thin films grown on polyethylene terephthalate (PET) substrates was investigated. It was found that the properties of such flexible transparent conductive oxide (TCO)/PET electrodes critically depend on this parameter. The TCO films that were deposited at distances of 6 and 8 cm exhibited an optical transmittance higher than 90% in the visible range and electrical resistivities around 5 × 10 −4 Ω cm. In addition to these excellent electrical and optical characteristics the films grown at 8 cm distance were homogenous, smooth, adherent, and without cracks or any other extended defects, being suitable for opto-electronic device applications.

  17. Operating method of amorphous thin film semiconductor element

    Energy Technology Data Exchange (ETDEWEB)

    Mori, Koshiro; Ono, Masaharu; Hanabusa, Akira; Osawa, Michio; Arita, Takashi

    1988-05-31

    The existing technologies concerning amorphous thin film semiconductor elements are the technologies concerning the formation of either a thin film transistor or an amorphous Si solar cell on a substrate. In order to drive a thin film transistor for electronic equipment control by the output power of an amorphous Si solar cell, it has been obliged to drive the transistor weth an amorphous solar cell which was formed on a substrate different from that for the transistor. Accordingly, the space for the amorphous solar cell, which was formed on the different substrate, was additionally needed on the substrate for the thin film transistor. In order to solve the above problem, this invention proposes an operating method of an amorphous thin film semiconductor element that after forming an amorphous Si solar cell through lamination on the insulation coating film which covers the thin film transistor formed on the substrate, the thin film transistor is driven by the output power of this solar cell. The invention eliminates the above superfluous space and reduces the size of the amorphous thin film semiconductor element including the electric source. (3 figs)

  18. Low resistivity of Ni–Al co-doped ZnO thin films deposited by DC magnetron sputtering at low sputtering power

    Energy Technology Data Exchange (ETDEWEB)

    Lee, JongWoo [Department of Materials Science and Engineering, Pusan National University, San 30 Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Hui, K.N. [Department of Mechanical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Hui, K.S., E-mail: kshui@hanyang.ac.kr [Department of Mechanical Engineering, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Cho, Y.R., E-mail: yescho@pusan.ac.kr [Department of Materials Science and Engineering, Pusan National University, San 30 Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Chun, Ho-Hwan [Global Core Research Center for Ships and Offshore Plants (GCRC-SOP), Pusan National University, San 30 Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea, Republic of)

    2014-02-28

    Ni–Al co-doped ZnO (NiAl:ZnO) thin films were deposited on glass substrates by DC magnetron sputtering in Ar using a single ceramic, spark-plasma-sintered target with 2 wt% Al and 5 wt% Ni. The effects of the sputtering power and gas pressure on the NiAl:ZnO films were studied. The structural, electrical, and optical properties of the films were characterized by X-ray diffraction, field emission scanning electron microscopy, Hall effect measurements and UV–vis transmission spectroscopy. As the sputtering power and gas pressure increased, the crystallinity, electrical properties and optical band gap of the films were improved. The NiAl:ZnO film deposited at 40 W at 6.0 mTorr had the strongest (0 0 2) XRD peak and the lowest resistivity of approximately 2.19 × 10{sup −3} Ω cm with an optical transmittance of 90%.

  19. Metal-insulator transition in tin doped indium oxide (ITO) thin films: Quantum correction to the electrical conductivity

    OpenAIRE

    Deepak Kumar Kaushik; K. Uday Kumar; A. Subrahmanyam

    2017-01-01

    Tin doped indium oxide (ITO) thin films are being used extensively as transparent conductors in several applications. In the present communication, we report the electrical transport in DC magnetron sputtered ITO thin films (prepared at 300 K and subsequently annealed at 673 K in vacuum for 60 minutes) in low temperatures (25-300 K). The low temperature Hall effect and resistivity measurements reveal that the ITO thin films are moderately dis-ordered (kFl∼1; kF is the Fermi wave vector and l ...

  20. A new concept in polymeric thin-film composite nanofiltration membranes with antibacterial properties.

    Science.gov (United States)

    Mollahosseini, Arash; Rahimpour, Ahmad

    2013-01-01

    A new, thin film, biofouling resistant, nanofiltration (NF) membrane was fabricated with two key characteristics, viz. a low rate of silver (Ag) release and long-lasting antibacterial properties. In the new approach, nanoparticles were embedded completely in a polymeric thin-film layer. A comparison was made between the new thin-film composite (TFC), NF membrane and thin-film nanocomposite (TFN), and antibacterial NF membranes. Both types of NF membrane were fabricated by interfacial polymerization on a polysulphone sublayer using m-phenylenediamine and trimesoyl chloride as an amine monomer and an acid chloride monomer, respectively. Energy dispersive X-ray (EDX) microanalysis demonstrated the presence of Ag nanoparticles. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to study the cross-sectional and surface morphological properties of the NF membranes. Permeability and salt rejection were tested using a dead-end filtration cell. Ag leaching from the membranes was measured using inductively coupled mass spectrometry (ICP-MS). Morphological studies showed that the TFC NF membranes had better thin-film formation (a more compact structure and a smoother surface) than TFN NF membranes. Performance experiments on TFC NF membranes revealed that permeability was good, without sacrificing salt rejection. The antibacterial properties of the fabricated membranes were tested using the disk diffusion method and viable plate counts. The antibiofouling properties of the membranes were examined by measuring the quantity of bacterial cells released from the biofilm formed (as a function of the amount of biofilm present). A more sensitive surface was observed compared to that of a typical antibacterial NF membrane. The Ag leaching rates were low, which will likely result in long-lasting antibacterial and biofouling resistant properties.

  1. Temperature dependence of LRE-HRE-TM thin films

    Science.gov (United States)

    Li, Zuoyi; Cheng, Xiaomin; Lin, Gengqi; Li, Zhen; Huang, Zhixin; Jin, Fang; Wang, Xianran; Yang, Xiaofei

    2003-04-01

    Temperature dependence of the properties of RE-TM thin films is very important for MO recording. In this paper, we studied the temperature dependence of the magnetic and magneto-optical properties of the amorphous LRE-HRE-TM single layer thin films and LRE-HRE-TM/HRE-TM couple-bilayered thin films. For LRE-HRE-TM single layer thin films, the temperature dependence of the magnetization was investigated by using the mean field theory. The experimental and theoretical results matched very well. With the LRE substitution in HRE-TM thin film, the compensation temperature Tcomp decreased and the curie temperature Tc remained unchanged. Kerr rotation angle became larger and the saturation magnetization Ms at room temperature increased. For LRE-HRE-TM/HRE-TM couple-bilayered thin films, comparisons of the temperature dependences of the coercivities and Kerr rotation angles were made between isolated sublayers and couple-bilayered thin film.

  2. Electrodeposition of diamond-like carbon films on titanium alloy using organic liquids: Corrosion and wear resistance

    International Nuclear Information System (INIS)

    Falcade, Tiago; Shmitzhaus, Tobias Eduardo; Gomes dos Reis, Otávio; Vargas, André Luis Marin; Hübler, Roberto; Müller, Iduvirges Lourdes; Fraga Malfatti, Célia de

    2012-01-01

    Highlights: ► The electrodeposition may be conducted at room temperature. ► The DLC films have good resistance to corrosion in saline environments. ► The films have lower coefficient of friction than the uncoated substrate. ► The abrasive wear protection is evident in coated systems. - Abstract: Diamond-like carbon (DLC) films have been studied as coatings for corrosion protection and wear resistance because they have excellent chemical inertness in traditional corrosive environments, besides presenting a significant reduction in coefficient of friction. Diamond-like carbon (DLC) films obtained by electrochemical deposition techniques have attracted a lot of interest, regarding their potential in relation to the vapor phase deposition techniques. The electrochemical deposition techniques are carried out at room temperature and do not need vacuum system, making easier this way the technological transfer. At high electric fields, the organic molecules polarize and react on the electrode surface, forming carbon films. The aim of this work was to obtain DLC films onto Ti6Al4V substrate using as electrolyte: acetonitrile (ACN) and N,N-dimethylformamide (DMF). The films were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), Raman spectroscopy, potentiodynamic polarization and wear tests. The results show that these films can improve, significantly, the corrosion resistance of titanium and its alloys and their wear resistance.

  3. Observation of feature ripening inversion effect at the percolation threshold for the growth of thin silver films

    Energy Technology Data Exchange (ETDEWEB)

    Nehm, Frederik, E-mail: frederik.nehm@iapp.de; Schubert, Sylvio; Müller-Meskamp, Lars; Leo, Karl

    2014-04-01

    The growth behavior of thin silver films on organic layers is investigated during deposition by means of simultaneous in-situ monitoring of sheet resistance and transmittance. Thermally evaporated films up to 11 nm show a distinct percolation behavior with strong resistance drop at the percolation thickness. Additionally, evaporations are divided into a sequence of one nanometer steps. In the deposition breaks, the films exhibit a ripening effect with an inversion at the percolation thickness, by changing from an increasing to decreasing sheet resistance over time. Scanning electron micrographs suggest same ripening mechanisms for islands below the percolation thickness as for holes above. - Highlights: • Fundamental understanding of metal thin film growth is presented. • Optical and electrical in-situ measurements used for optimizing transparent electrodes • Stepwise Ag deposition reveals extraordinary ripening effects. • Feature ripening inversion is discovered at the percolation threshold.

  4. Observation of feature ripening inversion effect at the percolation threshold for the growth of thin silver films

    International Nuclear Information System (INIS)

    Nehm, Frederik; Schubert, Sylvio; Müller-Meskamp, Lars; Leo, Karl

    2014-01-01

    The growth behavior of thin silver films on organic layers is investigated during deposition by means of simultaneous in-situ monitoring of sheet resistance and transmittance. Thermally evaporated films up to 11 nm show a distinct percolation behavior with strong resistance drop at the percolation thickness. Additionally, evaporations are divided into a sequence of one nanometer steps. In the deposition breaks, the films exhibit a ripening effect with an inversion at the percolation thickness, by changing from an increasing to decreasing sheet resistance over time. Scanning electron micrographs suggest same ripening mechanisms for islands below the percolation thickness as for holes above. - Highlights: • Fundamental understanding of metal thin film growth is presented. • Optical and electrical in-situ measurements used for optimizing transparent electrodes • Stepwise Ag deposition reveals extraordinary ripening effects. • Feature ripening inversion is discovered at the percolation threshold

  5. Determination of structural, mechanical and corrosion properties of Nb{sub 2}O{sub 5} and (Nb{sub y}Cu{sub 1−y})O{sub x} thin films deposited on Ti6Al4V alloy substrates for dental implant applications

    Energy Technology Data Exchange (ETDEWEB)

    Mazur, M. [Wroclaw University of Technology, Faculty of Microsystem Electronics and Photonics, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Kalisz, M., E-mail: malgorzata.kalisz@its.waw.pl [Motor Transport Institute, Jagiellońska 80, 03-301 Warsaw (Poland); Wojcieszak, D. [Wroclaw University of Technology, Faculty of Microsystem Electronics and Photonics, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Grobelny, M. [Motor Transport Institute, Jagiellońska 80, 03-301 Warsaw (Poland); Mazur, P. [Wroclaw University, Institute of Experimental Physics, Max Born 9, 50-204 Wroclaw (Poland); Kaczmarek, D.; Domaradzki, J. [Wroclaw University of Technology, Faculty of Microsystem Electronics and Photonics, Janiszewskiego 11/17, 50-372 Wroclaw (Poland)

    2015-02-01

    In this paper comparative studies on the structural, mechanical and corrosion properties of Nb{sub 2}O{sub 5}/Ti and (Nb{sub y}Cu{sub 1−y})O{sub x}/Ti alloy systems have been investigated. Pure layers of niobia and niobia with a copper addition were deposited on a Ti6Al4V titanium alloy surface using the magnetron sputtering method. The physicochemical properties of the prepared thin films were examined with the aid of XRD, XPS SEM and AFM measurements. The mechanical properties (i.e., nanohardness, Young's modulus and abrasion resistance) were performed using nanoindentation and a steel wool test. The corrosion properties of the coatings were determined by analysis of the voltammetric curves. The deposited coatings were crack free, exhibited good adherence to the substrate, no discontinuity of the thin film was observed and the surface morphology was homogeneous. The hardness of pure niobium pentoxide was ca. 8.64 GPa. The obtained results showed that the addition of copper into pure niobia resulted in the preparation of a layer with a lower hardness of ca. 7.79 GPa (for niobia with 17 at.% Cu) and 7.75 GPa (for niobia with 25 at.% Cu). The corrosion properties of the tested thin films deposited on the surface of titanium alloy depended on the composition of the thin layer. The addition of copper (i.e. a noble metal) to Nb{sub 2}O{sub 5} film increased the corrosion resistance followed by a significant decrease in the value of corrosion currents and, in case of the highest Cu content, the shift of corrosion potential towards the noble direction. The best corrosion properties were obtained from a sample of Ti6Al4V coated with (Nb{sub 0.75}Cu{sub 0.25})O{sub x} thin film. It seems that the tested materials could be used in the future as protection coatings for Ti alloys in biomedical applications such as implants. - Highlights: • Nb{sub 2}O{sub 5} and Nb{sub 2}O{sub 5}:Cu thin films were deposited on a Ti–Al–V surface using the magnetron sputtering.

  6. How Do Organic Vapors Swell Ultra-Thin PIM-1 Films?

    KAUST Repository

    Ogieglo, Wojciech

    2017-06-22

    Dynamic sorption of ethanol and toluene vapor into ultra-thin supported PIM-1 films down to 6 nm are studied with a combination of in-situ spectroscopic ellipsometry and in-situ X-ray reflectivity. Both ethanol and toluene significantly swell the PIM-1 matrix and, at the same time, induce persistent structural relaxations of the frozen-in glassy PIM-1 morphology. For ethanol below 20 nm three effects were identified. First, the swelling magnitude at high vapor pressures is reduced by about 30% as compared to thicker films. Second, at low penetrant activities (below 0.3 p/p0) films below 20 nm are able to absorb slightly more penetrant as compared with thicker films despite similar swelling magnitude. Third, for the ultra-thin films the onset of the dynamic penetrant-induced glass transition Pg has been found to shift to higher values indicating higher resistance to plasticization. All of these effects are consistent with a view where immobilization of the super-glassy PIM-1 at the substrate surface leads to an arrested, even more rigid and plasticization-resistant, yet still very open, microporous structure. PIM-1 in contact with the larger and more condensable toluene shows very complex, heterogeneous swelling dynamics and two distinct penetrant-induced relaxation phenomena, probably associated with the film outer surface and the bulk, are detected. Following the direction of the penetrant\\'s diffusion the surface seems to plasticize earlier than the bulk and the two relaxations remain well separated down to 6 nm film thickness, where they remarkably merge to form just a single relaxation.

  7. Effect of oxygen to argon flow ratio on the properties of Al-doped ZnO films for amorphous silicon thin film solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yang-Shih [Department of Materials Science and Engineering, National Chung Hsing University, Taichung 402, Taiwan, ROC (China); Lien, Shui-Yang, E-mail: syl@mdu.edu.tw [Department of Materials Science and Engineering, MingDao University, ChangHua 52345, Taiwan, ROC (China); Huang, Yung-Chuan [Department of Materials Science and Engineering, MingDao University, ChangHua 52345, Taiwan, ROC (China); Wang, Chao-Chun [Department of Materials Science and Engineering, National Chung Hsing University, Taichung 402, Taiwan, ROC (China); Liu, Chueh-Yang [Department of Materials Science and Engineering, MingDao University, ChangHua 52345, Taiwan, ROC (China); Nautiyal, Asheesh [Department of Mechanical Engineering, Yuan Ze University, 135 Yuan-Tung Road, Chungli, 320 Taoyuan, Taiwan, ROC (China); Wuu, Dong-Sing [Department of Materials Science and Engineering, National Chung Hsing University, Taichung 402, Taiwan, ROC (China); Lee, Shuo-Jun [Department of Mechanical Engineering, Yuan Ze University, 135 Yuan-Tung Road, Chungli, 320 Taoyuan, Taiwan, ROC (China)

    2013-02-01

    Transparent conductive oxide thin films in solar cell fabrication have attracted much attention due to their high conductivity and transmittance. In this paper, we have investigated the aluminum-doped zinc oxide (AZO) thin films prepared by radiofrequency magnetron sputtering on Asahi U-type SnO{sub 2} glass with different O{sub 2}/Ar flow ratios in vacuum chamber. Furthermore, the micro-structural, electrical, and optical properties of AZO/SnO{sub 2} films were studied. The change in O{sub 2}/Ar flow ratios is found to significantly affect the haze value, and slightly affect electrical resistivity and transmittance of the films. Afterward, the fabricated AZO thin films with different O{sub 2}/Ar flow ratios were used for building the solar cell devices. The current–voltage and external quantum efficiency characteristics were investigated for the solar cell devices. The optimized O{sub 2}/Ar flow ratio of 3 for solar device shows the best efficiency of 10.41%, and a 20% increase in short-circuit current density compared to typical Asahi solar cells. - Highlights: ► A thin Al-doped zinc oxide (AZO) film has been deposited on SnO{sub 2} substrates. ► The AZO film deposited at an O{sub 2}/Ar ratio of 3 shows low resistivity and high haze. ► The AZO film contains tiny grains that enhance light scattering. ► The amorphous silicon solar cell with the AZO layer shows a 20% increase in Jsc.

  8. Cobalt Xanthate Thin Film with Chemical Bath Deposition

    Directory of Open Access Journals (Sweden)

    İ. A. Kariper

    2013-01-01

    Full Text Available Cobalt xanthate thin films (CXTFs were successfully deposited by chemical bath deposition, onto amorphous glass substrates, as well as on p- and n-silicon, indium tin oxide, and poly(methyl methacrylate. The structure of the films was analyzed by far-infrared spectrum (FIR, mid-infrared (MIR spectrum, nuclear magnetic resonance (NMR, and scanning electron microscopy (SEM. These films were investigated from their structural, optical, and electrical properties point of view. Electrical properties were measured using four-point method, whereas optical properties were investigated via UV-VIS spectroscopic technique. Uniform distribution of grains was clearly observed from the photographs taken by scanning electron microscope (SEM. The transmittance was about 70–80% (4 hours, 50°C. The optical band gap of the CXTF was graphically estimated to be 3.99–4.02 eV. The resistivity of the films was calculated as 22.47–75.91 Ω·cm on commercial glass depending on film thickness and 44.90–73.10 Ω ·cm on the other substrates. It has been observed that the relative resistivity changed with film thickness. The MIR and FIR spectra of the films were in agreement with the literature analogues. The expected peaks of cobalt xanthate were observed in NMR analysis on glass. The films were dipped in chloroform as organic solvent and were analyzed by NMR.

  9. Tailoring and optimization of optical properties of CdO thin films for gas sensing applications

    Science.gov (United States)

    Rajput, Jeevitesh K.; Pathak, Trilok K.; Kumar, V.; Swart, H. C.; Purohit, L. P.

    2018-04-01

    Cadmium oxide (CdO) thin films have been deposited onto glass substrates using different molar concentrations (0.2 M, 0.5 M and 0.8 M) of cadmium acetate precursor solutions using a sol-gel spin coating technique. The structural, morphological, optical and electrical results are presented. X-ray diffraction patterns indicated that the CdO films of different molarity have a stable cubic structure with a (111) preferred orientation at low molar concentration. Scanning electron microscopy images revealed that the films adopted a rectangular to cauliflower like morphology. The optical transmittance of the thin films was observed in the range 200-800 nm and it was found that the 0.2 M CdO thin films showed about 83% transmission in the visible region. The optical band gap energy of the thin films was found to vary from 2.10 to 3.30 eV with the increase in molar concentration of the solution. The electrical resistance of the 0.5 M thin film was found to be 1.56 kΩ. The oxygen sensing response was observed between 20-33% in the low temperature range (32-200 °C).

  10. Synthesis of single phase of CuTl-1234 thin films

    CERN Document Server

    Khan, N A; Ishida, K; Tateai, F; Kojima, T; Terada, N; Ihara, H

    1999-01-01

    Thin films of CuTl-1234 superconductor have been prepared for the first time using an amorphous phase epitaxy method (APE). In this method, an amorphous phase is sputtered from a target of stoichiometric composition CuBa/sub 2/Ca/sub 3/Cu/sub 4/O/sub x/. Thin films on the SrTiO/sub 3/ substrate after the thallium treatment are biaxially oriented. The XRD reflected a predominant single phase with c-axis 18.7 AA and pole figure measurements of (103) reflections showed a-axis oriented films with Delta phi =0.8 degrees . Resistivity measurements showed T/sub c/=113 K and preliminary J/sub c/ measurements manifested a current density of 1.0*10/sup 6/ A/cm (77 K, 0 T). The composition of films after EDX measurements is Cu /sub 0.3/Tl/sub 0.7/CuBa/sub 2/Ca/sub 3/Cu/sub 4/O/sub 12-y/. (8 refs).

  11. Resistive switching properties of Ce and Mn co-doped BiFeO3 thin films for nonvolatile memory application

    Directory of Open Access Journals (Sweden)

    Zhenhua Tang

    2013-12-01

    Full Text Available The Ce and Mn co-doped BiFeO3 (BCFMO thin films were synthesized on Pt/Ti/SiO2/Si substrates using a sol-gel method. The unipolar resistive switching (URS and bipolar resistive switching (BRS behaviors were observed in the Pt/BCFMO/Pt device structure, which was attributed to the formation/rupture of metal filaments. The fabricated device exhibits a large ROFF/RON ratio (>80, long retention time (>105 s and low programming voltages (<1.5 V. Analysis of linear fitting current-voltage curves suggests that the space charge limited leakage current (SCLC and Schottky emission were observed as the conduction mechanisms of the devices.

  12. Liquid flow deposited spinel (Ni,Mn){sub 3}O{sub 4} thin films for microbolometer applications

    Energy Technology Data Exchange (ETDEWEB)

    Le, Duc Thang, E-mail: ducthang36@skku.edu [Intelligent Electronic Component Team, Electronic Materials Convergence Division, Korea Institute of Ceramic Engineering and Technology, Seoul 153-801 (Korea, Republic of); School of Advanced Materials Science & Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Jeon, Chang Jun; Lee, Kui Woong; Jeong, Young Hun; Yun, Ji Sun [Intelligent Electronic Component Team, Electronic Materials Convergence Division, Korea Institute of Ceramic Engineering and Technology, Seoul 153-801 (Korea, Republic of); Yoon, Dae Ho, E-mail: dhyoon@skku.edu [School of Advanced Materials Science & Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Cho, Jeong Ho, E-mail: goedc@kicet.re.kr [Intelligent Electronic Component Team, Electronic Materials Convergence Division, Korea Institute of Ceramic Engineering and Technology, Seoul 153-801 (Korea, Republic of)

    2015-03-01

    Highlights: • Highly quality (Ni,Mn){sub 3}O{sub 4} thin films were grown using liquid flow deposited (LFD) technique. • It is possible to deposit multi–component manganite–oxide thin films by LFD at low temperatures. • Nickel–manganite films showed a good negative temperature coefficient (NTC) characteristic. • Liquid flow deposited (Ni,Mn){sub 3}O{sub 4} thin films are very potential for microbolometer applications. - Abstract: A liquid flow deposition (LFD) technique was initially used for the fabrication of single-component Mn{sub 3}O{sub 4} thin films onto Si wafer substrates at a range of substrate temperatures of 30–80 °C, with the introduction of an oxidizing reagent (H{sub 2}O{sub 2}). As a result, solid thin films were well formed from an aqueous solution. An X-ray diffraction (XRD) analysis showed typical characteristics of hausmannite Mn{sub 3}O{sub 4} with a spinel tetragonal phase. Field-emission scanning electron microscopy (FE-SEM) observations revealed nano-sized grains arranged uniformly on a dense and smooth surface for all of the as-deposited films. On the other hand, the LFD method was then extended to prepare two-component nickel–manganite films according to the binary chemical composition of Ni{sub x}Mn{sub 3−x}O{sub 4} with x = 0.02–0.2. The as-grown nickel–manganite films showed a surface with a good quality with a spherical bead-like architecture when x ≤ 0.10, while a conversion from spherical grains into highly porous nanowalls in the microstructure was noted in films when x ≥ 0.12. These results signify that it is possible to fabricate various multi-component manganite-oxide thin films at a low temperature. In addition, the dependences of the room-temperature electrical resistivity (ρ) and the temperature coefficient of resistance (TCR) on the Ni substitution level (x) were investigated on films annealed at 400 °C.

  13. Application-related properties of giant magnetostrictive thin films

    International Nuclear Information System (INIS)

    Lim, S.H.; Kim, H.J.; Na, S.M.; Suh, S.J.

    2002-01-01

    In an effort to facilitate the utilization of giant magnetostrictive thin films in microdevices, application-related properties of these thin films, which include induced anisotropy, residual stress and corrosion properties, are investigated. A large induced anisotropy with an energy of 6x10 4 J/m 3 is formed in field-sputtered amorphous Sm-Fe-B thin films, resulting in a large magnetostriction anisotropy. Two components of residual stress, intrinsic compressive stress and tensile stress due to the difference of the thermal expansion coefficients between the substrate and thin film, are identified. The variation of residual stress with fabrication parameter and annealing temperature, and its influence on mechanical bending and magnetic properties are examined. Better corrosion properties are observed in Sm-Fe thin films than in Tb-Fe. Corrosion properties of Tb-Fe thin films, however, are much improved with the introduction of nitrogen to the thin films without deteriorating magnetostrictive properties

  14. Microbial colonization of biopolymeric thin films containing natural compounds and antibiotics fabricated by MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele (Romania); Surdu, A.V.; Grumezescu, A.M.; Oprea, A.E.; Trusca, R.; Vasile, O. [Faculty of Applied Chemistry and Materials Science, Department of Science and Engineering of Oxide Materials and Nanomaterials, Politehnica University of Bucharest, Polizu Street No. 1–7, 011061 Bucharest (Romania); Dorcioman, G.; Visan, A.; Socol, G.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele (Romania); Mihaiescu, D. [Faculty of Applied Chemistry and Materials Science, Department of Organic Chemistry, Politehnica University of Bucharest, 1–7 Polizu Street, 011061 Bucharest (Romania); Enculescu, M. [National Institute of Materials Physics, PO Box MG-7, Bucharest-Magurele (Romania); Chifiriuc, M.C. [Microbiology Immunology Department, Faculty of Biology, Research Institute of the University of Bucharest—ICUB, Research Institute of the University of Bucharest, 77206 Bucharest (Romania); Boehm, R.D.; Narayan, R.J. [Biomedical Engineering, University of North Carolina, Chapel Hill, NC (United States); Chrisey, D.B. [Department of Physics and Engineering Physics, Tulane University, New Orleans, LA (United States)

    2015-05-01

    Highlights: • We deposited thin composite quercetin/polyvinylpyrrolidone/antibiotic films with close resemblance to the starting/drop-cast composition by MAPLE. • Quercetin flavonoid shows an anti-biofilm activity comparable to that of the tested large-spectrum antibiotics (norfloxacin or cefuroxime), especially in case of 72 h biofilms. • These results could account for the possible use of quercetin as an alternative to antibiotics to combat the mature biofilms developed on different substrates. • MAPLE may be used to produce implantable medical devices that provide a relatively long term in vitro stability and resistance to the growth of microorganisms. - Abstract: Although a great number of antibiotics are currently available, they are often rendered ineffective by the ability of microbial strains to develop genetic resistance and to grow in biofilms. Since many antimicrobial agents poorly penetrate biofilms, biofilm-associated infections often require high concentrations of antimicrobial agents for effective treatment. Among the various strategies that may be used to inhibit microbial biofilms, one strategy that has generated significant interest involves the use of bioactive surfaces that are resistant to microbial colonization. In this respect, we used matrix assisted pulsed laser evaporation (MAPLE) involving a pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) to obtain thin composite biopolymeric films containing natural (flavonoid) or synthetic (antibiotic) compounds as bioactive substances. Chemical composition and film structures were investigated by Fourier transform infrared spectroscopy and X-ray diffraction. Films morphology was studied by scanning electron microscopy and transmission electron microscopy. The antimicrobial assay of the microbial biofilms formed on these films was assessed by the viable cell counts method. The flavonoid-containing thin films showed increased resistance to microbial colonization

  15. Microbial colonization of biopolymeric thin films containing natural compounds and antibiotics fabricated by MAPLE

    International Nuclear Information System (INIS)

    Cristescu, R.; Surdu, A.V.; Grumezescu, A.M.; Oprea, A.E.; Trusca, R.; Vasile, O.; Dorcioman, G.; Visan, A.; Socol, G.; Mihailescu, I.N.; Mihaiescu, D.; Enculescu, M.; Chifiriuc, M.C.; Boehm, R.D.; Narayan, R.J.; Chrisey, D.B.

    2015-01-01

    Highlights: • We deposited thin composite quercetin/polyvinylpyrrolidone/antibiotic films with close resemblance to the starting/drop-cast composition by MAPLE. • Quercetin flavonoid shows an anti-biofilm activity comparable to that of the tested large-spectrum antibiotics (norfloxacin or cefuroxime), especially in case of 72 h biofilms. • These results could account for the possible use of quercetin as an alternative to antibiotics to combat the mature biofilms developed on different substrates. • MAPLE may be used to produce implantable medical devices that provide a relatively long term in vitro stability and resistance to the growth of microorganisms. - Abstract: Although a great number of antibiotics are currently available, they are often rendered ineffective by the ability of microbial strains to develop genetic resistance and to grow in biofilms. Since many antimicrobial agents poorly penetrate biofilms, biofilm-associated infections often require high concentrations of antimicrobial agents for effective treatment. Among the various strategies that may be used to inhibit microbial biofilms, one strategy that has generated significant interest involves the use of bioactive surfaces that are resistant to microbial colonization. In this respect, we used matrix assisted pulsed laser evaporation (MAPLE) involving a pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) to obtain thin composite biopolymeric films containing natural (flavonoid) or synthetic (antibiotic) compounds as bioactive substances. Chemical composition and film structures were investigated by Fourier transform infrared spectroscopy and X-ray diffraction. Films morphology was studied by scanning electron microscopy and transmission electron microscopy. The antimicrobial assay of the microbial biofilms formed on these films was assessed by the viable cell counts method. The flavonoid-containing thin films showed increased resistance to microbial colonization

  16. Studies on Various Functional Properties of Titania Thin Film Developed on Glazed Ceramic Wall Tiles

    Science.gov (United States)

    Anil, Asha; Darshana R, Bangoria; Misra, S. N.

    A sol-gel based TiO2 thin film was applied on glazed wall tiles for studying its various functional properties. Thin film was deposited by spin coating on the substrate and subjected to curing at different temperatures such as 600°C, 650, 700°C, 750°C and 800°C with 10 minutes soaking. The gel powder was characterized by FTIR, DTA/TG and XRD. Microstructure of thin film was analyzed by FESEM and EDX. Surface properties of the coatings such as gloss, colour difference, stain resistance, mineral hardness and wettability were extensively studied. The antibacterial activity of the surface of coated substrate against E. coli was also examined. The durability of the coated substrate in comparison to the uncoated was tested against alkali in accordance with ISO: 10545 (Part 13):1995 standard. FESEM images showed that thin films are dense and homogeneous. Coated substrates after firing results in lustre with high gloss, which increased from 330 to 420 GU as the curing temperature increases compared to that of uncoated one (72 GU). Coated substrate cured at 800°C shows higher mineral hardness (5 Mohs’) compared to uncoated one (4 Mohs’) and films cured at all temperatures showed stain resistance. The experimental results showed that the resistance towards alkali attack increase with increase in curing temperature and alkali resistance of sample cured at 800 °C was found to be superior compared to uncoated substrate. Contact angle of water on coated surface of substrates decreased with increase in temperature. Bacterial reduction percentages of the coated surface was 97% for sample cured at 700°C and it decreased from 97% to 87% as the curing temperature increased to 800 °C when treated with E. coli bacteria.

  17. Optical properties of titanium trisulphide (TiS3) thin films

    International Nuclear Information System (INIS)

    Ferrer, I.J.; Ares, J.R.; Clamagirand, J.M.; Barawi, M.; Sánchez, C.

    2013-01-01

    Titanium trisulphide thin films have been grown on quartz substrates by sulphuration of electron-beam evaporated Ti layers (d ∼ 300 nm) in a vacuum sealed ampoule in the presence of sulphur powder at 550 °C for different periods of time (1 to 20 h). Thin films were characterized by X-ray diffraction, energy dispersive analyses of X-ray and scanning electron microscopy. Results demonstrate that films are composed by monoclinic titanium trisulphide. Films show n-type conductivity with a relatively high resistivity (ρ ∼ 4 ± 2 Ω·cm) and high values of the Seebeck coefficient (− 600 μV/K) at room temperature. Values of the optical absorption coefficient about α ∼ 10 5 cm −1 , determined from reflectance and transmittance measurements, have been obtained at photon energies hυ > 2 eV. The absorption coefficient dependence on the photon energy in the range of 1.6–3.0 eV hints the existence of a direct transition with an energy gap between 1.35 and 1.50 eV. By comparing these results with those obtained from bulk TiS 3 , a direct transition with lower energy is also found which could have been hidden due to the low value of the absorption coefficient in this energy range. - Highlights: ► Thin films of TiS 3 have been obtained by sulphuration of Ti layers. ► Optical properties of TiS 3 thin films have been determined. ► Optical energy gap of TiS 3 has been obtained. ► Optical properties of bulk TiS 3 have been measured and compared with those of films

  18. Effects of atomic oxygen on titanium dioxide thin film

    Science.gov (United States)

    Shimosako, Naoki; Hara, Yukihiro; Shimazaki, Kazunori; Miyazaki, Eiji; Sakama, Hiroshi

    2018-05-01

    In low earth orbit (LEO), atomic oxygen (AO) has shown to cause degradation of organic materials used in spacecrafts. Similar to other metal oxides such as SiO2, Al2O3 and ITO, TiO2 has potential to protect organic materials. In this study, the anatese-type TiO2 thin films were fabricated by a sol-gel method and irradiated with AO. The properties of TiO2 were compared using mass change, scanning electron microscope (SEM), atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmittance spectra and photocatalytic activity before and after AO irradiation. The results indicate that TiO2 film was hardly eroded and resistant against AO degradation. AO was shown to affects only the surface of a TiO2 film and not the bulk. Upon AO irradiation, the TiO2 films were slightly oxidized. However, these changes were very small. Photocatalytic activity of TiO2 was still maintained in spite of slight decrease upon AO irradiation, which demonstrated that TiO2 thin films are promising for elimination of contaminations outgassed from a spacecraft's materials.

  19. Reliability assessment of ultra-thin HfO{sub 2} films deposited on silicon wafer

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Wei-En [Center for Measurement Standards, Industrial Technology Research Institute, Room 216, Building 8, 321 Kuang Fu Road Sec. 2, Hsinchu, Taiwan (China); Chang, Chia-Wei [Department of Materials Science and Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Chang, Yong-Qing [Center for Measurement Standards, Industrial Technology Research Institute, Room 216, Building 8, 321 Kuang Fu Road Sec. 2, Hsinchu, Taiwan (China); Yao, Chih-Kai [Department of Materials Science and Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Liao, Jiunn-Der, E-mail: jdliao@mail.ncku.edu.tw [Department of Materials Science and Engineering, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China)

    2012-09-01

    Highlights: Black-Right-Pointing-Pointer Nano-mechanical properties on annealed ultra-thin HfO{sub 2} film are studied. Black-Right-Pointing-Pointer By AFM analysis, hardness of the crystallized HfO{sub 2} film significantly increases. Black-Right-Pointing-Pointer By nano-indention, the film hardness increases with less contact stiffness. Black-Right-Pointing-Pointer Quality assessment on the annealed ultra-thin films can thus be achieved. - Abstract: Ultra-thin hafnium dioxide (HfO{sub 2}) is used to replace silicon dioxide to meet the required transistor feature size in advanced semiconductor industry. The process integration compatibility and long-term reliability for the transistors depend on the mechanical performance of ultra-thin HfO{sub 2} films. The criteria of reliability including wear resistance, thermal fatigue, and stress-driven failure rely on film adhesion significantly. The adhesion and variations in mechanical properties induced by thermal annealing of the ultra-thin HfO{sub 2} films deposited on silicon wafers (HfO{sub 2}/SiO{sub 2}/Si) are not fully understood. In this work, the mechanical properties of an atomic layer deposited HfO{sub 2} (nominal thickness Almost-Equal-To 10 nm) on a silicon wafer were characterized by the diamond-coated tip of an atomic force microscope and compared with those of annealed samples. The results indicate that the annealing process leads to the formation of crystallized HfO{sub 2} phases for the atomic layer deposited HfO{sub 2}. The HfSi{sub x}O{sub y} complex formed at the interface between HfO{sub 2} and SiO{sub 2}/Si, where the thermal diffusion of Hf, Si, and O atoms occurred. The annealing process increases the surface hardness of crystallized HfO{sub 2} film and therefore the resistance to nano-scratches. In addition, the annealing process significantly decreases the harmonic contact stiffness (or thereafter eliminate the stress at the interface) and increases the nano-hardness, as measured by vertically

  20. Crystallization characteristic and scaling behavior of germanium antimony thin films for phase change memory.

    Science.gov (United States)

    Wu, Weihua; Zhao, Zihan; Shen, Bo; Zhai, Jiwei; Song, Sannian; Song, Zhitang

    2018-04-19

    Amorphous Ge8Sb92 thin films with various thicknesses were deposited by magnetron sputtering. The crystallization kinetics and optical properties of the Ge8Sb92 thin films and related scaling effects were investigated by an in situ thermally induced method and an optical technique. With a decrease in film thickness, the crystallization temperature, crystallization activation energy and data retention ability increased significantly. The changed crystallization behavior may be ascribed to the smaller grain size and larger surface-to-volume ratio as the film thickness decreased. Regardless of whether the state was amorphous or crystalline, the film resistance increased remarkably as the film thickness decreased to 3 nm. The optical band gap calculated from the reflection spectra increases distinctly with a reduction in film thickness. X-ray diffraction patterns confirm that the scaling of the Ge8Sb92 thin film can inhibit the crystallization process and reduce the grain size. The values of exponent indices that were obtained indicate that the crystallization mechanism experiences a series of changes with scaling of the film thickness. The crystallization time was estimated to determine the scaling effect on the phase change speed. The scaling effect on the electrical switching performance of a phase change memory cell was also determined. The current-voltage and resistance-voltage characteristics indicate that phase change memory cells based on a thinner Ge8Sb92 film will exhibit a higher threshold voltage, lower RESET operational voltage and greater pulse width, which implies higher thermal stability, lower power consumption and relatively lower switching velocity.

  1. Effect of target power on the physical properties of Ti thin films prepared by DC magnetron sputtering with supported discharge

    Directory of Open Access Journals (Sweden)

    Kavitha A.

    2017-02-01

    Full Text Available The present paper describes the effect of target power on the properties of Ti thin films prepared by DC magnetron sputtering with (triode mode and without (diode mode supported discharge. The traditional diode magnetron sputtering with an addition of a hot filament has been used to sustain the discharge at a lower pressure. The effect of target power (60, 80, 100 and 120 W on the physical properties of Ti thin films has been studied in diode and triode modes. XRD studies showed that the Ti thin films prepared at a target power up to 100 W in diode mode were amorphous in nature. The Ti thin films exhibited crystalline structure at much lower target power of 80 W with a preferred orientation along (0 0 2 plane. The grain size of Ti thin films prepared in triode mode increased from 64 nm to 80 nm, whereas in diode mode, the grain size increased from 2 nm to 5 nm. EDAX analysis confirmed that the incorporation of reactive gases was lower in triode mode compared to diode mode. The electrical resistivity of Ti thin films deposited in diode mode was found to be 85 µΩ⋅cm (target power 120 W. The electrical resistivity of Ti thin films in triode mode was found to be deceased to 15.2 µΩ⋅cm (target power 120 W.

  2. Photodiode Based on CdO Thin Films as Electron Transport Layer

    Science.gov (United States)

    Soylu, M.; Kader, H. S.

    2016-11-01

    Cadmium oxide (CdO) thin films were synthesized by the sol-gel method. The films were analyzed by means of XRD, AFM, and UV/Vis spectrophotometry. X-ray diffraction patterns confirm that the films are formed from CdO with cubic crystal structure and consist of nano-particles. The energy gap of the prepared film was found to be 2.29 eV. The current-voltage ( I- V) characteristics of the CdO/ p-Si heterojunction were examined in the dark and under different illumination intensities. The heterojunction showed high rectifying behavior and a strong photoresponse. Main electrical parameters of the photodiode such as series and shunt resistances ( R s and R sh), saturation current I 0, and photocurrent I ph, were extracted considering a single diode equivalent circuit of a photovoltaic cell. Results indicate that the application of CdO thin films as an electron transport layer on p-Si acts as a photodetector in the field of the UV/visible.

  3. Influence of oxygen flow rate on metal-insulator transition of vanadium oxide thin films grown by RF magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xu; Liu, Xinkun; Li, Haizhu; Huang, Mingju [Henan University, Key Lab of Informational Opto-Electronical Materials and Apparatus, School of Physics and Electronics, Kaifeng (China); Zhang, Angran [South China Normal University, Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, Guangzhou (China)

    2017-03-15

    High-quality vanadium oxide (VO{sub 2}) films have been fabricated on Si (111) substrates by radio frequency (RF) magnetron sputtering deposition method. The sheet resistance of VO{sub 2} has a significant change (close to 5 orders of magnitude) in the process of the metal-insulator phase transition (MIT). The field emission-scanning electron microscope (FE-SEM) results show the grain size of VO{sub 2} thin films is larger with the increase of oxygen flow. The X-ray diffraction (XRD) results indicate the thin films fabricated at different oxygen flow rates grow along the (011) crystalline orientation. As the oxygen flow rate increases from 3 sccm to 6 sccm, the phase transition temperature of the films reduces from 341 to 320 K, the width of the thermal hysteresis loop decreases from 32 to 9 K. The thin films fabricated in the condition of 5 sccm have a high temperature coefficient of resistance (TCR) -3.455%/K with a small resistivity of 2.795 ρ/Ω cm. (orig.)

  4. Evaluation of unencapsulated ceramic monolithic and MOS thin-film capacitors (25 to 3000C)

    International Nuclear Information System (INIS)

    Nance, W.R.

    1982-01-01

    Several commercial monolithic ceramic and thin-film MOS chip capacitors were evaluated for use in high temperature (300 0 C) geothermal instrumentation. Characteristics of the commonly used dielectric materials (NPO, X7R, BX) and temperature dependence of the insulation resistance are briefly discussed. Some ceramic capacitors with NPO dielectric materials had insulation resistances above 10 megohms at 300 0 C and less than 2% change in capacitance from 25 0 C to 300 0 C, while the X7R and BX dielectric materials exhibited insulation resistances below 10 megohm and changes in capacitance greater then 50%. The thin-film capacitors showed good stability at 300 0 C. However, during aging, bonds and bond pads presented a problem causing intermittently open circuits for some of the devices

  5. Thermoelectric properties of cobalt–antimonide thin films prepared by radio frequency co-sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Aziz; Han, Seungwoo, E-mail: swhan@kimm.re.kr

    2015-07-31

    Co–Sb thin films with an Sb content in the range 65–76 at.%, were deposited on a thermally oxidized Si (100) substrate preheated at 200 °C using radio-frequency co-sputtering. Evaluation using scanning electron microscopy images and X-ray diffraction reveals that the films were polycrystalline, with a grain size in the range 100–250 nm. Energy-dispersive spectroscopy analysis indicates single-phase CoSb{sub 2} and CoSb{sub 3} films, as well as multiphase thin films with either CoSb{sub 2} or CoSb{sub 3} as the dominant phase. The electrical and thermoelectric properties were measured and found to be strongly dependent on the observed phases and the defect concentrations. The CoSb{sub 2} thin films were found to exhibit a significant n-type thermoelectric effect, which, coupled with the very low electrical resistivity, resulted in a larger power factor than that of the CoSb{sub 3} thin films. We find power factors of 0.73 mWm{sup −1} K{sup −2} and 0.67 mWm{sup −1} K{sup −2} for the CoSb{sub 2} and CoSb{sub 3} thin films, respectively. - Highlights: • Polycrystalline Co–Sb thin films were obtained by present deposition strategy. • CoSb{sub 2} and CoSb{sub 3} have semimetal and semiconductor characteristics respectively. • The Seebeck coefficient depends heavily on defect concentration and impurity phases. • Film properties in the second heating cycle were different from the first. • CoSb{sub 2} is found to possess significant n-type thermopower.

  6. Deposition of indium tin oxide thin films by cathodic arc ion plating

    International Nuclear Information System (INIS)

    Yang, M.-H.; Wen, J.-C.; Chen, K.-L.; Chen, S.-Y.; Leu, M.-S.

    2005-01-01

    Indium tin oxide (ITO) thin films have been deposited by cathodic arc ion plating (CAIP) using sintered oxide target as the source material. In an oxygen atmosphere of 200 deg. C, ITO films with a lowest resistivity of 2.2x10 -4 Ω-cm were obtained at a deposition rate higher than 450 nm/min. The carrier mobility of ITO shows a maximum at some medium pressures. Although morphologically ITO films with a very fine nanometer-sized structure were observed to possess the lowest resistivity, more detailed analyses based on X-ray diffraction are attempted to gain more insight into the factors that govern electron mobility in this investigation

  7. ZnO:Al thin films deposited by RF-magnetron sputtering with tunable and uniform properties.

    Science.gov (United States)

    Miorin, E; Montagner, F; Battiston, S; Fiameni, S; Fabrizio, M

    2011-03-01

    Nanostructured, high quality and large area Al-doped ZnO (ZnO:Al) thin films were obtained by radiofrequency (RF) magnetron sputtering. The sample rotation during deposition has resulted in excellent spatial distribution of thickness and electro-optical properties compared to that obtained under static conditions. ZnO:Al thin films are employed in a large number of devices, including thin film solar cells, where the uniformity of the properties is a key factor for a possible up-scaling of the research results to industrially relevant substrate sizes. A chemical post etching treatment was employed achieving tunable surface nanotextures to generate light scattering at the desired wavelength for improved cell efficiency. Since the film resistivity is only slightly increased by the etching, this post-deposition step allows separating the optimization of electro-optical properties from light scattering behavior. The thin films were characterized by FE-SEM, XRD, UV-VIS spectroscopy, four probe and van der Paw techniques.

  8. Effect of dopants and thermal treatment on properties of Ga-Al-ZnO thin films fabricated by hetero targets sputtering system

    International Nuclear Information System (INIS)

    Hong, JeongSoo; Matsushita, Nobuhiro; Kim, KyungHwan

    2013-01-01

    In this study, we fabricated Ga and Al doped ZnO (Ga-Al-ZnO; GAZO) thin films by using the facing targets sputtering system under various conditions such as input current and thermal treatment temperature. The properties of the as-deposited GAZO thin films were examined by four-point, UV/Vis spectrometry, X-ray diffraction, atomic force microscopy and field-emission scanning electron microscopy. The result showed that the lowest sheet resistance of the films was 59.3 ohm/sq and transmittance was about 85%. After thermal treatment, the properties of GAZO thin films were improved. The lowest sheet resistance (47.3 ohm/sq) of the GAZO thin films were obtained at thermal treatment temperature of 300 °C, considered to be the result of continuous substitutions by dopants and improved crystallinity by the thermal treatment. - Highlights: ► Ga and Al doped ZnO thin films were prepared by hetero targets sputtering system. ► Free electrons were increased due to the continuous substitutions of Ga and Al. ► Crystallinity was improved by recombination of particles with increasing of temperature

  9. Preparation of LiMn2O4 cathode thin films for thin film lithium secondary batteries by a mist CVD process

    International Nuclear Information System (INIS)

    Tadanaga, Kiyoharu; Yamaguchi, Akihiro; Sakuda, Atsushi; Hayashi, Akitoshi; Tatsumisago, Masahiro; Duran, Alicia; Aparacio, Mario

    2014-01-01

    Highlights: • LiMn 2 O 4 thin films were prepared by using the mist CVD process. • An aqueous solution of lithium and manganese acetates is used for the precursor solution. • The cell with the LiMn 2 O 4 thin films exhibited a capacity of about 80 mAh/g. • The cell showed good cycling performance during 10 cycles. - Abstract: LiMn 2 O 4 cathode thin films for thin film lithium secondary batteries were prepared by using so-called the “mist CVD process”, employing an aqueous solution of lithium acetate and manganese acetate, as the source of Li and Mn, respectively. The aqueous solution of starting materials was ultrasonically atomized to form mist particles, and mists were transferred by nitrogen gas to silica glass substrate to form thin films. FE-SEM observation revealed that thin films obtained by this process were dense and smooth, and thin films with a thickness of about 750 nm were obtained. The electrochemical cell with the thin films obtained by sintering at 700 °C exhibited a capacity of about 80 mAh/g, and the cell showed good cycling performance during 10 cycles

  10. P-type CuxS thin films: Integration in a thin film transistor structure

    International Nuclear Information System (INIS)

    Nunes de Carvalho, C.; Parreira, P.; Lavareda, G.; Brogueira, P.; Amaral, A.

    2013-01-01

    Cu x S thin films, 80 nm thick, are deposited by vacuum thermal evaporation of sulfur-rich powder mixture, Cu 2 S:S (50:50 wt.%) with no intentional heating of the substrate. The process of deposition occurs at very low deposition rates (0.1–0.3 nm/s) to avoid the formation of Cu or S-rich films. The evolution of Cu x S films surface properties (morphology/roughness) under post deposition mild annealing in air at 270 °C and their integration in a thin film transistor (TFT) are the main objectives of this study. Accordingly, Scanning Electron Microscopy studies show Cu x S films with different surface morphologies, depending on the post deposition annealing conditions. For the shortest annealing time, the Cu x S films look to be constructed of grains with large dimension at the surface (approximately 100 nm) and consequently, irregular shape. For the longest annealing time, films with a fine-grained surface are found, with some randomly distributed large particles bound to this fine-grained surface. Atomic Force Microscopy results indicate an increase of the root-mean-square roughness of Cu x S surface with annealing time, from 13.6 up to 37.4 nm, for 255 and 345 s, respectively. The preliminary integration of Cu x S films in a TFT bottom-gate type structure allowed the study of the feasibility and compatibility of this material with the remaining stages of a TFT fabrication as well as the determination of the p-type characteristic of the Cu x S material. - Highlights: • Surface properties of annealed Cu x S films. • Variation of conductivity with annealing temperatures of Cu x S films. • Application of evaporated Cu x S films in a thin film transistor (TFT) structure. • Determination of Cu x S p-type characteristic from TFT behaviour

  11. Abrasive wear of ceramic wear protection at ambient and high temperatures

    Science.gov (United States)

    Varga, M.; Adam, K.; Tumma, M.; Alessio, K. O.

    2017-05-01

    Ceramic wear protection is often applied in abrasive conditions due to their excellent wear resistance. This is especially necessary in heavy industries conveying large amounts of raw materials, e.g. in steel industry. Some plants also require material transport at high temperatures and velocities, making the need of temperature stable and abrasion resistant wear protection necessary. Various types and wear behaviour of ceramic protection are known. Hence, the goal of this study is to identify the best suitable ceramic materials for abrasive conditions in harsh environments at temperatures up to 950°C and severe thermal gradients. Chamottes, known for their excellent thermal shock resistance are compared to high abrasion resistant ceramic wear tiles and a cost efficient cement-bounded hard compound. Testing was done under high-stress three-body abrasion regime with a modified ASTM G65 apparatus enabling for investigations up to ~950°C. Thereto heated abrasive is introduced into the wear track and also preheated ceramic samples were used and compared to ambient temperature experiments. Results indicate a significant temperature influence on chamottes and the hard compound. While the chamottes benefit from temperature increase, the cement-bounded hard compound showed its limitation at abrasive temperatures of 950°C. The high abrasion resistant wear tiles represented the materials with the best wear resistance and less temperature influence in the investigated range.

  12. Semiconductor-nanocrystal/conjugated polymer thin films

    Science.gov (United States)

    Alivisatos, A. Paul; Dittmer, Janke J.; Huynh, Wendy U.; Milliron, Delia

    2014-06-17

    The invention described herein provides for thin films and methods of making comprising inorganic semiconductor-nanocrystals dispersed in semiconducting-polymers in high loading amounts. The invention also describes photovoltaic devices incorporating the thin films.

  13. Effect of hydrogen doping on the properties of Al and F co-doped ZnO films for thin film silicon solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Fang-Hsing, E-mail: fansen@dragon.nchu.edu.tw; Yang, Tung-Hsin

    2016-04-30

    Aluminum and fluorine co-doped zinc oxide (AFZO) thin films were prepared in Ar + H{sub 2} atmospheres by rf magnetron sputtering at room temperature. The structural, electrical, and optical properties of the prepared films were investigated using X-ray diffraction, scanning electron microscopy, atomic force microscopy, Hall-effect measurement, X-ray photoelectron spectroscopy, and ultraviolet–visible spectrometry, and their dependence on deposition atmosphere (i.e. H{sub 2} / (H{sub 2} + Ar) ratio) was studied. The resulting films showed a (0 0 2) diffraction peak, indicating a typical wurtzite structure, and the optimal film crystallinity was obtained with the H{sub 2} / (H{sub 2} + Ar) ratio of 3%. The electrical resistivity of AFZO films decreased to 9.16 × 10{sup −4} Ω-cm, which was lower than ZnO:Al and ZnO:F films due to double doping effect of Al and F. The resistivity further decreased to below 5 × 10{sup −4} Ω-cm for the AFZO film with the H{sub 2} / (H{sub 2} + Ar) ratio of 3%–5%. All the films regardless of hydrogen content displayed high transmittances (> 92%) in the visible wavelength range. Applying the developed AFZO films as front transparent electrodes, amorphous Si thin film solar cells were fabricated and the open-circuit voltage, fill factor, and efficiency of the cell with the hydrogenated AFZO film were improved in contrast to those without the hydrogenated film. - Highlights: • H{sub 2} doping improves optoelectronic properties of Al, F co-doped ZnO (AFZO) films. • Resistivity of AFZO films decreases to 4.4 × 10{sup −4} Ω-cm with the 3% H{sub 2}/(Ar + H{sub 2}) ratio. • AFZO films show high average visible transmittances of above 92%. • Efficiency of a-Si thin film solar cells is improved by AFZO:H as front electrode.

  14. Thin liquid films dewetting and polymer flow

    CERN Document Server

    Blossey, Ralf

    2012-01-01

    This book is a treatise on the thermodynamic and dynamic properties of thin liquid films at solid surfaces and, in particular, their rupture instabilities. For the quantitative study of these phenomena, polymer thin films haven proven to be an invaluable experimental model system.   What is it that makes thin film instabilities special and interesting, warranting a whole book? There are several answers to this. Firstly, thin polymeric films have an important range of applications, and with the increase in the number of technologies available to produce and to study them, this range is likely to expand. An understanding of their instabilities is therefore of practical relevance for the design of such films.   Secondly, thin liquid films are an interdisciplinary research topic. Interdisciplinary research is surely not an end to itself, but in this case it leads to a fairly heterogeneous community of theoretical and experimental physicists, engineers, physical chemists, mathematicians and others working on the...

  15. Self-assembly of dodecaphenyl POSS thin films

    Science.gov (United States)

    Handke, Bartosz; Klita, Łukasz; Niemiec, Wiktor

    2017-12-01

    The self-assembly abilities of Dodecaphenyl Polyhedral Oligomeric Silsesquioxane thin films on Si(1 0 0) surfaces were studied. Due to their thermal properties - relatively low sublimation temperature and preservation of molecular structure - cage type silsesquioxanes are ideal material for the preparation of a thin films by Physical Vapor Deposition. The Ultra-High Vacuum environment and the deposition precision of the PVD method enable the study of early stages of thin film growth and its molecular organization. X-ray Reflectivity and Atomic Force Microscopy measurements allow to pursuit size-effects in the structure of thin films with thickness ranges from less than a single molecular layer up to several tens of layers. Thermal treatment of the thin films triggered phase change: from a poorly ordered polycrystalline film into a well-ordered multilayer structure. Self-assembly of the layers is the effect of the π-stacking of phenyl rings, which force molecules to arrange in a superlattice, forming stacks of alternating organic-inorganic layers.

  16. Enhanced electrical and optical properties of CdS:Na thin films by photochemical deposition

    Science.gov (United States)

    Kumar, V. Nirmal; Suriakarthick, R.; Gopalakrishnan, R.; Hayakawa, Y.

    2017-06-01

    CdS:Na thin film was deposited on a glass substrate by photochemical deposition from aqueous solution contained CdSO4.5H2O and Na2S2O3 as cation and anion sources, respectively. The anion source Na2S2O3 served as Na dopant source. The deposited film exhibited cubic phase of CdS and incorporation of Na was revealed from X-ray diffraction study. The incorporation of Na in CdS changed the surface morphology from spherical to nano rods. CdS:Na thin film showed blue shift in its absorption spectrum which was more desirable for transmitting higher energy photons (visible region) in thin film solar cells. The Raman analysis confirmed 1 LO and 2 LO process at 297 and 593 cm-1, respectively. The carrier concentration of CdS increased with the inclusion of Na and its resistivity value decreased. Both the electrical and optical properties of CdS were enhanced in CdS:Na thin films which was desirable as a window layer material for photovoltaic application.

  17. The influence of nanoscale morphology on the resistivity of cluster-assembled nanostructured metallic thin films

    International Nuclear Information System (INIS)

    Barborini, E; Bertolini, G; Repetto, P; Leccardi, M; Vinati, S; Corbelli, G; Milani, P

    2010-01-01

    We have studied in situ the evolution of the electrical resistivity of Fe, Pd, Nb, W and Mo cluster-assembled films during their growth by supersonic cluster beam deposition. We observed resistivity of cluster-assembled films several orders of magnitude larger than the bulk, as well as an increase in resistivity by increasing the film thickness in contrast to what was observed for atom-assembled metallic films. This suggests that the nanoscale morphological features typical of ballistic films growth, such as the minimal cluster-cluster interconnection and the evolution of surface roughness with thickness, are responsible for the observed behaviour.

  18. Giant spin Hall angle from topological insulator BixSe(1 - x) thin films

    Science.gov (United States)

    Dc, Mahendra; Jamali, Mahdi; Chen, Junyang; Hickey, Danielle; Zhang, Delin; Zhao, Zhengyang; Li, Hongshi; Quarterman, Patrick; Lv, Yang; Mkhyon, Andre; Wang, Jian-Ping

    Investigation on the spin-orbit torque (SOT) from large spin-orbit coupling materials has been attracting interest because of its low power switching of the magnetization and ultra-fast driving of the domain wall motion that can be used in future spin based memory and logic devices. We investigated SOT from topological insulator BixSe(1 - x) thin film in BixSe(1 - x) /CoFeB heterostructure by using the dc planar Hall method, where BixSe(1 - x) thin films were prepared by a unique industry-compatible deposition process. The angle dependent Hall resistance was measured in the presence of a rotating external in-plane magnetic field at bipolar currents. The spin Hall angle (SHA) from this BixSe(1 - x) thin film was found to be as large as 22.41, which is the largest ever reported at room temperature (RT). The giant SHA and large spin Hall conductivity (SHC) make this BixSe(1 - x) thin film a very strong candidate as an SOT generator in SOT based memory and logic devices.

  19. Study of post annealing influence on structural, chemical and electrical properties of ZTO thin films

    International Nuclear Information System (INIS)

    Jain, Vipin Kumar; Kumar, Praveen; Kumar, Mahesh; Jain, Praveen; Bhandari, Deepika; Vijay, Y.K.

    2011-01-01

    Research highlights: → Structural, chemical and electrical properties of cost effective ZTO thin films with varying concentrations. → Effect of annealing of ZTO films. - Abstract: Zinc-Tin-Oxide (ZTO) thin films were deposited on glass substrate with varying concentrations (ZnO:SnO 2 ; 100:0, 90:10, 70:30 and 50:50 wt.%) at room temperature by flash evaporation technique. These deposited ZTO films were annealed at 450 deg. C in vacuum. These films were characterized to study the effect of annealing and addition of SnO 2 concentration on the structural, chemical and electrical properties. The XRD analysis indicates that crystallization of the ZTO films strongly depends on the concentration of SnO 2 and post annealing where annealed films showed polycrystalline nature. Atomic force microscopy (AFM) images manifest the surface morphology of these ZTO thin films. The XPS core level spectra of Zn(2p), O(1s) and Sn(3d) have been deconvoluted into their Gaussian component to evaluate the chemical changes, while valence band spectra reveal the electronic structures of these films. A small shift in Zn(2p) and Sn(3d) core level towards higher binding energy and O(1s) core level towards lower binding energy have been observed. The minimum electrical resistivity (ρ ∼ 3.69 x 10 -2 Ω-cm), maximum carrier concentration (n ∼ 3.26 x 10 19 cm -3 ) and Hall mobility (μ ∼ 5.2 cm 2 v -1 s -1 ) were obtained for as-prepared ZTO (50:50) film thereafter move towards lowest resistivity (ρ ∼ 1.12 x 10 -3 Ω-cm), highest carrier concentration (n ∼ 2.96 x 10 20 cm -3 ) and mobility (μ ∼ 18.8 cm 2 v -1 s -1 ) for annealed ZTO (50:50) thin film.

  20. Nitriding the influence of plasma in resistance to wear micro abrasive tool steel AISI D2

    International Nuclear Information System (INIS)

    Gobbi, Vagner Joao; Gobb, Silvio Jose; Silva, Cosme Roberto Moreira da

    2010-01-01

    This work studies the influence of time of treatment in the formation of nitride layer of AISI D2 tool steel and the resistance to micro-abrasive wear from the technique of nitriding in plasma. The samples were nitrides at 400 ° C with a pressure of 4.5 mbar (450 Pa) and using a gas mixture of 80% vol.H2 and 20% vol.N2. The times of treatment were: 30, 60, 120, 180 and 360 minutes. The properties of the layers in the samples obtained nitrides were assessed by surface microhardness, profiles of microhardness, metallography analysis, X-ray diffraction and test for resistance to micro-abrasive wear. The best results for nitriding to 400 deg C, was obtained with the time of treatment of 360 minutes. In this case the increase in surface hardness was 94.6% and resistance to micro-abrasive wear of 15%. This increase in hardness may be associated with high concentration of nitrogen in the crystalline network of iron-α and additional training of nitrides. Low temperature of nitriding reduces between grain fragility to reduce the likelihood of precipitation of nitrides in a continuous manner in the austenite grain boundaries and the absence of previous ε'+ γ phases. (author)