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Sample records for ag thin films

  1. Underlayer Roughness Influence on the Properties of ag Thin Film

    Science.gov (United States)

    Zhao, Pei; Wang, Reng; Liu, Dingquan; Zhang, Fengshan; Su, Weitao; Xu, Xiaofeng

    The effects of the roughness of ZnS underlayer on the microstructure, optical, and electrical properties of nanometer Ag thin film have been investigated in this paper. Nanometer Ag thin films in glass/ZnS/7.5 nm Ag/30 nm ZnS stacks have been deposited and analyzed. In the stacks, the underlayers of ZnS have been sputtered with various thicknesses to generate various surface roughnesses. The X-ray diffraction (XRD) has been used to study the crystal structure of Ag films. The surface topography and the roughness of ZnS underlayer have been analyzed by atomic force microscopy. The sheet resistant will become larger as the increasing of the roughness. The optical constants can be derived by fitting the transmission and reflectance spectrum. From optical constants comparison of Ag films, with the surface of the stack becoming rougher, it was found that the refractive index will increase but the extinction coefficient will decrease.

  2. Realization of Ag-S codoped p-type ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Tian Ning, E-mail: xtn9886@zju.edu.cn [Department of Science, Zhijiang College of Zhejiang University of Technology, Hangzhou, Zhejiang 310024 (China); Department of Physics, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang 310027 (China); Li, Xiang; Lu, Zhong [Department of Science, Zhijiang College of Zhejiang University of Technology, Hangzhou, Zhejiang 310024 (China); Chen, Yong Yue [Department of Physics, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang 310027 (China); Sui, Cheng Hua [Department of Science, Zhijiang College of Zhejiang University of Technology, Hangzhou, Zhejiang 310024 (China); Wu, Hui Zhen [Department of Physics, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang 310027 (China)

    2014-10-15

    Highlights: • Ag-S codoped p-type ZnO thin films have been fabricated. • The films exhibit low resistivity and high Hall mobility and hole concentration. • A ZnO:(Ag, S)/i-ZnO/ZnO:Al homojunction has been fabricated and shows rectifying behaviors. - Abstract: Ag-S codoped ZnO films have been grown on quartz substrates by e-beam evaporation at low temperature (100 °C). The effects of Ag{sub 2}S content on the structural and electrical properties of the films were investigated. The results showed that 2 wt% Ag{sub 2}S doped films exhibited p-type conduction, with a resistivity of 0.0347 Ω cm, a Hall mobility of 9.53 cm{sup 2} V{sup −1} s{sup −1}, and a hole concentration of 1.89 × 10{sup 19} cm{sup −3} at room temperature. The X-ray photoelectron spectroscopy measurements showed that Ag and S have been incorporated into the films. To further confirm the p-type conduction of Ag-S codoped ZnO films, a ZnO:(Ag, S)/i-ZnO/ZnO:Al homojunction was fabricated and rectifying behaviors of which was measured. High electrical performance and low growth temperature indicate that Ag{sub 2}S is a promising dopant to fabricate p-type Ag-S codoped ZnO films.

  3. TRIBOLOGICAL PROPERTIES OF CrAgN THIN FILMS

    Directory of Open Access Journals (Sweden)

    Peter Jurči

    2013-04-01

    Full Text Available CrN and CrAgN thin films were magnetron sputtered onto the substrate made from Vanadis 6 cold work tool steel. The films were examined on tribological properties using a high temperature Pin-on-disc tribometer. Obtained results show that there is almost no effect of Ag addition on the friction coefficient when tested at a room temperature against alumina. The testing against the same counterpart at higher temperature gave positive effect of the silver addition on the friction coefficient. The testing against 100Cr6 ball bearing steel gave higher friction coefficient than that against alumina while the testing against CuSn6-bronze led to much lower μ. When tested at a room temperature, the wear performance of the films was positively affected only in the case of the CrAg3N film developed at 500 °C. On the other hand, addition of 3 wt% Ag into the CrN increased the wear performance at elevated temperatures while the addition of 15 wt% Ag has made the film too soft and sensitive to wear.

  4. Tribological properties of CrAgN thin films

    Directory of Open Access Journals (Sweden)

    Peter Jurči

    2013-02-01

    Full Text Available CrN and CrAgN thin films were magnetron sputtered onto the substrate made from Vanadis 6 cold work tool steel. The films were examined on tribological properties using a high temperature Pin-on-disc tribometer. Obtained results show that there is almost no effect of Ag addition on the friction coefficient when tested at a room temperature against alumina. The testing against the same counterpart at higher temperature gave positive effect of the silver addition on the m. The testing against 100Cr6 ball bearing steel gave higher friction coefficient than that against alumina while the testing against CuSn6-bronze led to much lower m. When tested at a room temperature, the wear performance of the films was positively affected only in the case of the CrAg3N film developed at 500 oC. On the other hand, addition of 3 wt% Ag into the CrN increased the wear performance at elevated temperatures while the addition of 15 wt% Ag has made the film too soft and sensitive to wear.

  5. Preparation and Properties of Ag-TiO2 Thin Films on Glass Substrates

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Ag-TiO2 thin films were prepared on glasses.The morphology and structure of Ag-TiO2 films were investigated by XRD, SEM and FT-IR.The photocatalytic and hydrophilic properties of Ag-TiO2 thin films were also evaluated by examining photocatalytic degradation dichlorophos under sunlight illumination and the change of contact angle respectively.The research results show that the Ag-TiO2 thin film is mainly composed of 20-100nm Ag and TiO2 particles.The Ag-TiO2 thin films possess a super-hydrophilic ability and higher photocatalytic activity than that of pure TiO2 thin film.

  6. Ferroelectric domain of epitaxial AgNbO3 thin film

    Science.gov (United States)

    Ahn, Yoonho; Seo, Jeongdae; Lee, Kwang Jo; Son, Jong Yeog

    2016-03-01

    We investigated ferroelectric properties of silver niobate (AgNbO3) thin film grown on Nb-doped SrTiO3 substrate by pulsed laser deposition. The AgNbO3 thin film exhibited room temperature ferroelectricity with a large remanent polarization of about 31 μC/cm2 (2Pr~62 μC/cm2) and fast switching behavior within 120 ns. Triangular grains of AgNbO3 thin film were observed by atomic force microscopy (AFM). The piezoelectric force microscopy (PFM) study revealed that the AgNbO3 thin film had mosaic-like ferroelectric domain structure. In comparison with PbTiO3 thin films, domain size of the AgNbO3 thin films was smaller than that of PbTiO3 thin films. Based on Landau, Lifshitz, and Kittel (LLK) scaling law of the domain size versus film thickness curves, it is inferred that AgNbO3 thin films have slightly lower domain wall energy than that of PbTiO3 thin films.

  7. Effect of microstructure on thermal conductivity of Cu, Ag thin films.

    Science.gov (United States)

    Ryu, Sang; Juhng, Woonam; Kim, Youngman

    2010-05-01

    Thin film type materials are widely used in modern industries, such as semiconductor devices, functional superconductors, machining tools, and so on. The thermal properties of material in semiconductor are very important factors for stable operation because the heat generated during device operation may increase clock frequency. Even though thermal properties of thin films may play a major role in assessing reliability of parts, the measurement methods of thin film thermal properties are generally known to be complex to devise. In this study, a temperature distribution method was applied for the measurement of thermal conductivity of Cu and Ag thin film on borosilicate glass substrate. Cu and Ag thin films were deposited on borosilicate glass using thermal evaporation processes. To measure the thermal conductivity changes according to the microstructure of metallic thin film, the processing variables for the Cu and Ag thin film deposition were changed. To minimize the effect of film thickness, the film thickness was fixed to the thickness of approximately 500 nm throughout experiments. The thermal conductivities of thin films were measured to be much lower than those of bulk materials. Thin film with larger grain size showed higher thermal conductivity probably due to the lower number density of grain boundary. Weidman-Franz law could be applied to thin films produced in this study. Thermal conductivity was also estimated from the resistivity of thin film and Lorenz number of bulk material.

  8. Tensoresistive Properties of Thin Film Systems Based on Ag and Co

    Directory of Open Access Journals (Sweden)

    I.M. Pazukha

    2012-10-01

    Full Text Available The results of research strain deformation properties of thin films Ag, Co and two-layers films Ag/Co in the range of deformation Δεl = 0-1 % were presented. The plastic deformation in Co layer caused a similar deformation in the entire film system, even if the strain range Ag layer is not reached the limits of the transition elastic/plastic deformation. The increasing of gauge factor value of two-layer systems in comparison with thin films Ag and Co appears as a result of electron interface scattering.

  9. Study on swift heavy ions induced modifications of Ag-ZnO nanocomposite thin film

    Science.gov (United States)

    Singh, S. K.; Singhal, R.; Siva Kumar, V. V.

    2017-03-01

    In the present work, swift heavy ion (SHI) irradiation induced modifications in structural and optical properties of Ag-ZnO nanocomposite thin films have been investigated. Ag-ZnO nanocomposite (NCs) thin films were synthesized by RF magnetron sputtering technique and irradiated with 100 MeV Ag7+ ions at three different fluences 3 × 1012, 1 × 1013 and 3 × 1013 ions/cm2. Rutherford Backscattering Spectrometry revealed Ag concentration to be ∼8.0 at.%, and measured thickness of the films was ∼55 nm. Structural properties of pristine and irradiated films have been analyzed by X-ray diffraction analysis and found that variation in crystallite size of the film with ion irradiation. X-ray photoelectron spectroscopy (XPS) indicates the formation of Ag-ZnO nanocomposite thin film with presence of Ag, Zn and O elements. Oxidation state of Ag and Zn also estimated by XPS analysis. Surface plasmon resonance (SPR) of Ag nanoparticle has appeared at ∼475 nm in the pristine thin film, which is blue shifted by ∼30 nm in film irradiated at fluence of 3 × 1012 ions/cm2 and completely disappeared in film irradiated at higher fluences, 1 × 1013 and 3 × 1013 ions/cm2. A marginal change in the optical band gap of Ag-ZnO nanocomposite thin film is also found with increasing ion fluence. Surface morphology of pristine and irradiated films have been studied using Atomic Force Microscopy (AFM). Raman and Photo-luminance (PL) spectra of nanocomposite thin films have been investigated to understand the ion induced modifications such as lattice defects and disordering in the nanocomposite thin film.

  10. AgSbSe{sub 2} and AgSb(S,Se){sub 2} thin films for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Garza, J.G. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Shaji, S. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Facultad de Ingenieria Mecanica y Electrica, CIIDIT - Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico); Rodriguez, A.C.; Das Roy, T.K. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Krishnan, B., E-mail: kbindu_k@yahoo.com [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Facultad de Ingenieria Mecanica y Electrica, CIIDIT - Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico)

    2011-10-01

    Silver antimony selenide (AgSbSe{sub 2}) thin films were prepared by heating sequentially deposited multilayers of antimony sulphide (Sb{sub 2}S{sub 3}), silver selenide (Ag{sub 2}Se), selenium (Se) and silver (Ag). Sb{sub 2}S{sub 3} thin film was prepared from a chemical bath containing SbCl{sub 3} and Na{sub 2}S{sub 2}O{sub 3}, Ag{sub 2}Se from a solution containing AgNO{sub 3} and Na{sub 2}SeSO{sub 3} and Se thin films from an acidified solution of Na{sub 2}SeSO{sub 3}, at room temperature on glass substrates. Ag thin film was deposited by thermal evaporation. The annealing temperature was 350 deg. C in vacuum (10{sup -3} Torr) for 1 h. X-ray diffraction analysis showed that the thin films formed were polycrystalline AgSbSe{sub 2} or AgSb(S,Se){sub 2} depending on selenium content in the precursor films. Morphology and elemental analysis of these films were done using scanning electron microscopy and energy dispersive X-ray spectroscopy. Optical band gap was evaluated from the UV-visible absorption spectra of these films. Electrical characterizations were done using Hall effect and photocurrent measurements. A photovoltaic structure: glass/ITO/CdS/AgSbSe{sub 2}/Al was formed, in which CdS was deposited by chemical bath deposition. J-V characteristics of this structure showed V{sub oc} = 435 mV and J{sub sc} = 0.08 mA/cm{sup 2} under illumination using a tungsten halogen lamp. Preparation of a photovoltaic structure using AgSbSe{sub 2} as an absorber material by a non-toxic selenization process is achieved.

  11. Preparation of Ag-doped TiO2 Thin Film by Sol-gel Method

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Ag-TiO2 thin film has been prepared on glass substrate by sol-gel process. The structure and properties of the materials were studied by DTA, XRD, and EPR.The photocatalytic activity was examined by the photocatalytic degradation of dichlorophos. The analysis results indicate that the photocatalytic activity of the Ag-TiO2 thin film is higher than that of pure TiO2 thin film. It is also influenced by the content of anatase and heating temperature. The ESR result shows that the Ag-TiO2 thin film has more hydroxide radicals than pure TiO2 thin film after illuminated by UV light.

  12. Effect of silver growth temperature on the contacts between Ag and ZnO thin films

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Highly c-axis oriented ZnO thin films were deposited on Si substrates by the pulsed laser deposition (PLD) method. At different growth temperatures,200 nm silver films as the contact metal were deposited on the ZnO thin films. The growth temperatures have great influence on the crystal quality of Ag films. Current-voltage characteristics were measured at room temperature. The Schottky contacts between Ag and ZnO thin films were successfully obtained when silver electrodes were deposited at 150 ℃ and 200℃. Ohmic contacts were formed while the growth temperatures were lower than 150℃ or higher than 200 ℃. After analysis,the forming of Ag/ZnO Schottky contacts was shown to be dependent on the appearance of the p-type inversion layer at the interface between Ag and ZnO layers.

  13. Effect of silver growth temperature on the contacts between Ag and ZnO thin films

    Institute of Scientific and Technical Information of China (English)

    LI XinKun; LI QingShan; LIANG DeChun; XU YanDong; XIE XiaoJun

    2009-01-01

    Highly c-axis oriented ZnO thin films were deposited on Si substrates by the pulsed laser deposition (PLD) method. At different growth temperatures, 200 nm silver films as the contact metal were depos-ited on the ZnO thin films. The growth temperatures have great influence on the crystal quality of Ag films. Current-voltage characteristics were measured at room temperature. The Schottky contacts be-tween Ag and ZnO thin films were successfully obtained when silver electrodes were deposited at 150℃ and 200℃. Ohmic contacts were formed while the growth temperatures were lower than 150℃ or higher than 200℃. After analysis, the forming of Ag/ZnO Schottky contacts was shown to be dependent on the appearance of the p-type inversion layer at the interface between Ag and ZnO layers.

  14. Enhanced optical absorption by Ag nanoparticles in a thin film Si solar cell

    Institute of Scientific and Technical Information of China (English)

    Chen Feng-Xiang; Wang Li-Sheng; Xu Wen-Ying

    2013-01-01

    Thin film solar cells have the potential to significantly reduce the cost of photovoltaics.Light trapping is crucial to such a thin film silicon solar cell because of a low absorption coefficient due to its indirect band gap.In this paper,we investigate the suitability of surface plasmon resonance Ag nanoparticles for enhancing optical absorption in the thin film solar cell.For evaluating the transmittance capability of Ag nanoparticles and the conventional antireflection film,an enhanced transmittance factor is introduced.We find that under the solar spectrum AM1.5,the transmittance of Ag nanoparticles with radius over 160 nm is equivalent to that of conventional textured antireflection film,and its effect is better than that of the planar antireflection film.The influence of the surrounding medium is also discussed.

  15. Ag Nanodots Emitters Embedded in a Nanocrystalline Thin Film Deposited on Crystalline Si Solar Cells.

    Science.gov (United States)

    Park, Seungil; Ryu, Sel Gi; Ji, HyungYong; Kim, Myeong Jun; Peck, Jong Hyeon; Kim, Keunjoo

    2016-06-01

    We fabricated crystalline Si solar cells with the inclusion of various Ag nanodots into the additional emitters of nanocrystallite Si thin films. The fabricated process was carried out on the emitter surface of p-n junction for the textured p-type wafer. The Ag thin films were deposited on emitter surfaces and annealed at various temperatures. The amorphous Si layers were also deposited on the Ag annealed surfaces by hot-wire chemical vapor deposition and then the deposited layers were doped by the second n-type doping process to form an additional emitter. From the characterization, both the Ag nanodots and the deposited amorphous Si thin films strongly reduce photo-reflectances in a spectral region between 200-400 nm. After embedding Ag nanodots in nanocrystallite Si thin films, a conversion efficiency of the sample with added emitter was achieved to 15.1%, which is higher than the 14.1% of the reference sample and the 14.7% of the de-posited sample with a-Si:H thin film after the Ag annealing process. The additional nanocrystallite emitter on crystalline Si with Ag nanodots enhances cell properties.

  16. Enhanced photoelectrochemical performance of Ag-ZnO thin films synthesized by spray pyrolysis technique

    Energy Technology Data Exchange (ETDEWEB)

    Tarwal, N.L. [Thin Film Materials Laboratory, Department of Physics, Shivaji University, Vidyanagar, Kolhapur 416004, Maharashtra (India); Patil, P.S., E-mail: psp_phy@unishivaji.ac.in [Thin Film Materials Laboratory, Department of Physics, Shivaji University, Vidyanagar, Kolhapur 416004, Maharashtra (India)

    2011-07-15

    Highlights: > Synthesis of Ag-ZnO nanocomposites by spray pyrolysis technique. > Examine the effect of Ag doping on the structural, morphological optical, and photoelectrochemical properties. > Surface Plasmon Resonance phenomenon of the spray deposited Ag-ZnO nanocomposites. > Enhancement in photoelectrochemical performance of ZnO thin films after Ag doping. - Abstract: Silver doped zinc oxide (Ag-ZnO) thin films were deposited on glass and tin doped indium oxide (ITO) coated glass substrates by using pneumatic spray pyrolysis technique (SPT) at 450 deg. C from aqueous solutions of zinc acetate and silver nitrate precursors. The effect of silver doping on structural, morphological and optical properties of films was studied. The XRD spectra of the Ag-ZnO films indicate the polycrystalline nature having hexagonal crystal structure. SEM micrographs show the uniform distribution of spherical grains of about 80-90 nm grain size for the pure ZnO thin films. The Ag nanoparticles are clearly visualized in SEM images of Ag-ZnO samples. The optical band gap energy decreases as the percentage of silver doping increases. Surface Plasmon Resonance (SPR) related phenomena are observed and correlated to the optical properties of Ag-ZnO thin films. The overall photoelectrochemical (PEC) performance of the samples was investigated and discussed. Moreover, the samples are more photoactive as compare to the pure ZnO sample and the sample ZnOAg{sub 15} shows the highest current. The photocurrent increases upto 249 {mu}A cm{sup -2} and 303 {mu}A cm{sup -2} in visible light and in UV illumination, respectively, and then decreases as the Ag doping increases into the film.

  17. Effect of Ag Doping on Optical and Electrical Properties of ZnO Thin Films

    Institute of Scientific and Technical Information of China (English)

    XU Jin; ZHANG Zi-Yu; ZHANG Yang; LIN Bi-Xia; FU Zhu-Xi

    2005-01-01

    @@ ZnO thin films were prepared on p-type Si (100) substrates by the sol-gel process. The influence of Ag doping at a content of 0.002 % on the photoluminescence and current-voltage (Ⅰ - Ⅴ) characteristics of ZnO thin films has been investigated. It is found that Ag doping leads to a pronounced increase in the intensity of near band edge emission at 3.23 eV and a remarkable red shift of the visible broadband at room temperature. The Ⅰ - Ⅴ characteristics of ZnO/p-Si hetero junctions are also changed. These results could be explained by Ag substituting for Zn in Ag doped ZnO thin films.

  18. Influence of Ag and Sn incorporation in In2S3 thin films

    Science.gov (United States)

    Lin, Ling-Yan; Yu, Jin-Ling; Cheng, Shu-Ying; Lu, Pei-Min

    2015-07-01

    Ag- and Sn-doped In2S3 thin films were deposited on glass substrates using the thermal evaporation technique. The doping was realized by thermal diffusion. The influences of Ag and Sn impurities on the electrical, structural, morphological, and optical properties of the In2S3 films were investigated. In all deposited samples, the x-ray diffraction spectra revealed the formation of cubic In2S3 phase. A significant increase in the crystallite size was observed after Ag doping, while the doping of Sn slightly decreased the crystallite size. The x-ray photoelectron spectroscopy verified the diffusion of Ag and Sn into the In2S3 films after annealing. The optical study illustrated that Ag doping resulted in a reduction of the optical band gap while Sn doping led to a widening of the gap. Optical properties were investigated to determine the optical constants. Besides, it was found that the resistivity decreases significantly either after Ag or Sn incorporation. The study demonstrates that the Sn-doped In2S3 thin films are more suitable for buffer layer application in solar cells than the Ag-doped In2S3 thin films. Project supported by the National Natural Science Foundation of China (Grant Nos. 61076063, 61340051, and 61306120) and the Natural Science Foundation of Fujian Province, China (Grant No. 2014J05073).

  19. Microstructures and magnetic properties of [SiO2/FePt]5/Ag thin films

    Institute of Scientific and Technical Information of China (English)

    FAN Jiu-ping; XU Xiao-hong; JIANG Feng-xian; TIAN Bao-qiang; WU Hai-shun

    2008-01-01

    [SiO2/FePt]5/Ag thin films were deposited by RF magnetron sputtering on the glass substrates and post annealing at 550 ℃for 30 min in vacuum. Vibrating sample magnetometer and X-ray diffraction analyser were applied to study the magnetic properties and microstructures of the films. The results show that without Ag underlayer [SiO2/FePt]5 films deposited onto the glass are FCC disordered; with the addition of Ag underlayer [SiO2/FePt]5/Ag films are changed into L10 and (111) mixed texture. The variation of the SiO2 nonmagnetic layer thickness in [SiO2/FePt]5/Ag films indicates that SiO2-doping plays an important role in improving the order parameter and the perpendicular magnetic anisotropy, and reducing the grain size and intergrain interactions. By controllingSiO2 thickness the highly perpendicular magnetic anisotropy can be obtained in the [SiO2 (0. 6nm)/FePt (3 nm)]5/Ag (50 nm) films and highly (001)-oriented films can be obtained in the [SiO2 (2 nm)/FePt (3 nm)]5/Ag (50 nm) films.

  20. Optical properties of silver sulphide thin films formed on evaporated Ag by a simple sulphurization method

    Energy Technology Data Exchange (ETDEWEB)

    Barrera-Calva, E., E-mail: ebc@xanum.uam.m [Departamento de Ingenieria de Procesos e hidraulica, Universidad Autonoma Metropolitana - Iztapalapa, Av. Purisima Esq. Michoacan, Col. Vicentina, Mexico, D.F., 09340 (Mexico); Ortega-Lopez, M.; Avila-Garcia, A.; Matsumoto-Kwabara, Y. [Departamento de Ingenieria Electrica, Centro de Investigacion y de Estudios Avanzados del IPN, Mexico DF 07360 (Mexico)

    2010-01-31

    Silver sulphide (Ag{sub 2}S) thin films were grown on the surface of silver films (Ag) deposited on glass substrate by using a simple chemical sulphurization method. According to X-ray diffraction analysis, the Ag{sub 2}S thin films display low intensity peaks at 34.48{sup o}, 36.56{sup o}, and 44.28{sup o}, corresponding to diffraction from (100), (112) and (103) planes of the acanthite phase (monoclinic). A model of the type Ag{sub 2}S/Ag/glass was deduced from spectroscopic ellipsometric measurements. Also, the optical constants (n, k) of the system were determined. Furthermore, the optical properties as solar selective absorber for collector applications were assessed. The optical reflectance of the Ag{sub 2}S/Ag thin film systems exhibits the expected behavior for an ideal selective absorber, showing a low reflectance in the wavelength range below 2 {mu}m and a high reflectance for wavelengths higher than that value. An absorptance about 70% and an emittance about 3% or less were calculated for several samples.

  1. Sputtered Ag thin films with modified morphologies: Influence on wetting property

    Energy Technology Data Exchange (ETDEWEB)

    Dutheil, P., E-mail: perrine.dutheil@univ-orleans.fr [GREMI, UMR 7344- Université D’Orléans, 14 rue d’Issoudun, BP 6744, Orléans 45067 (France); Thomann, A.L.; Lecas, T.; Brault, P. [GREMI, UMR 7344- Université D’Orléans, 14 rue d’Issoudun, BP 6744, Orléans 45067 (France); Vayer, M. [ICMN, UMR 7374- Université D’Orléans, 1b rue de la Férollerie, Orléans 45071 (France)

    2015-08-30

    Graphical abstract: - Highlights: • Ag thin films are deposited by DC magnetron sputtering on Si and W/Si layers. • The influence of the W underlayer morphology on Ag film growth is evidenced. • Variation of the Ag growth mode and roughness is investigated by SEM and AFM. • Wetting property is correlated to the roughness of Ag deposits on Si and W layers. - Abstract: Silver thin films with thickness ranging from 3 nm to 33 nm were sputter deposited onto silicon wafers and tungsten layers. Those W layers were previously synthesized in the same DC magnetron sputter deposition system with various experimental conditions (argon pressure, target to substrate distance) in order to stabilize different surface morphologies. SEM observations and AFM images showed that the growth mode of Ag films is similar on Si substrates and on the smoothest W layers, whereas it is modified for rough W layers made of sharp grains. The effect of the W layer morphology on Ag film growth was clearly evidenced when the deposition took place at high temperature. It is seen that performing the deposition onto substrates of various morphologies allows tailoring the wetting property of the Ag deposit.

  2. Irradiation induced improvement in crystallinity of epitaxially grown Ag thin films on Si substrates

    Energy Technology Data Exchange (ETDEWEB)

    Takahiro, Katsumi; Nagata, Shinji; Yamaguchi, Sadae [Tohoku Univ., Sendai (Japan). Inst. for Materials Research

    1997-03-01

    We report the improvement in crystallinity of epitaxially grown Ag films on Si(100) substrates with ion irradiation. The irradiation of 0.5 MeV Si ions to 2x10{sup 16}/cm{sup 2} at 200degC, for example, reduces the channeling minimum yield from 60% to 6% at Ag surface. The improvement originates from the decrease of mosaic spread in the Ag thin film. In our experiments, ion energy, ion species and irradiation temperature have been varied. The better crystallinity is obtained as the higher concentration of defect is generated. The mechanism involved in the irradiation induced improvement is discussed. (author)

  3. NUMERICAL CHARACTERIZATION OF CURRENT-INDUCED CHANGES IN SURFACE MORPHOLOGY OF THIN Ag FILMS

    Institute of Scientific and Technical Information of China (English)

    A. V. Panin; H.-G. Chun; A.R. Shugurov; S. V. Panin; N. V. Pykhtin

    2003-01-01

    The changes in surface topography of thin conducting Ag films under high-density current condition are studied by optical and scanning tunnelling microscopy (STM).It is established that the loss of conductivity in specimens occurs through depletion of the material due to their overheating and electromigration process. It has been shown that the r.m.s. Roughness, the fractal dimension of voids and the fractal dimension of the surface allow complete numerical characterization of surface topography changes in thin Ag films.

  4. A study of Ag/Ag(100) thin film growth with scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Wen, J.

    1995-11-01

    Thin films are attracting more and more attention in both the industrial and scientific communities. Many applications of thin films have been developed in industry. By using various growth methods, thin films can be used in optics, microelectronic devices, magnetic recording media, and as protective coatings. In order to improve existing applications and to find new ones, it is essential to understand what makes them so useful in applications and what factors affect their properties. Therefore, an understanding of film growth processes is necessary. Scientifically, many fundamental interactions, such as the interaction between the atoms that comprise the film and substrate, or the interaction between film atoms, are of great interest to surface scientists; studies of these interactions can provide dramatic insights into the nature of thin films and therefore, can further drive technology forward. In every application, the film structures, including morphology and microstructure, and adhesion between film and substrate are critical to the film`s properties and therefore its performance. Studies of the mechanisms that control film morphology, microstructure and adhesion thus are important. Film growth kinetics can provide important information regarding the film structure and adhesion. Film growth is an atomistic process. The chemistry and physics of the system can be better understood if the information provided is at an atomic level.

  5. Synthesis, characterization and photocatalytic behavior of Ag doped TiO2 thin film

    Science.gov (United States)

    Bensouici, F.; Souier, T.; Dakhel, A. A.; Iratni, A.; Tala-Ighil, R.; Bououdina, M.

    2015-09-01

    In this study, structure, microstructure, optical properties and photocatalytic degradation of Rhodamine B (RhB) have been investigated in an aqueous heterogeneous media containing pure and Ag doped TiO2 nanostructures thin films which were prepared by a simple sol-gel route. Thermal analysis demonstrated that Ag content decreased the temperature of anatase-to-rutile phase transformation. X-ray diffraction analysis confirmed that the prepared nanostructures crystallize within anatase-type structure and that the dopant Ag ions were not fully incorporated within TiO2 host lattice, meanwhile both the refractive index and optical band gap were affected by Ag concentration. The photodegradation of Rhodamine B under UV-C radiation by using pure and Ag-doped TiO2 nanostructures showed that Ag played an important role in a significant improvement of the photodegradation efficiency and that the optimum content of Ag ions was found to be 0.5% molar ratio.

  6. The Effect of Cu:Ag Atomic Ratio on the Properties of Sputtered Cu–Ag Alloy Thin Films

    Directory of Open Access Journals (Sweden)

    Janghsing Hsieh

    2016-11-01

    Full Text Available Cu–Ag thin films with various atomic ratios were prepared using a co-sputtering technique, followed by rapid thermal annealing at various temperatures. The films’ structural, mechanical, and electrical properties were then characterized using X-ray diffractometry (XRD, atomic force microscopy (AFM, FESEM, nano-indentation, and TEM as functions of compositions and annealing conditions. In the as-deposited condition, the structure of these films transformed from a one-phase to a dual-phase state, and the resistivity shows a twin-peak pattern, which can be explained in part by Nordheim’s Rule and the miscibility gap of Cu–Ag alloy. After being annealed, the films’ resistivity followed the mixture rule in general, mainly due to the formation of a dual-phase structure containing Ag-rich and Cu-rich phases. The surface morphology and structure also varied as compositions and annealing conditions changed. The recrystallization of these films varied depending on Ag–Cu compositions. The annealed films composed of 40 at % to 60 at % Cu had higher hardness and lower roughness than those with other compositions. Particularly, the Cu50Ag50 film had the highest hardness after being annealed. From the dissolution testing, it was found that the Cu-ion concentration was about 40 times higher than that of Ag. The galvanic effect and over-saturated state could be the cause of the accelerated Cu dissolution and the reduced dissolution of the Ag.

  7. Influence of the surface properties on bactericidal and fungicidal activity of magnetron sputtered Ti–Ag and Nb–Ag thin films

    Energy Technology Data Exchange (ETDEWEB)

    Wojcieszak, D., E-mail: damian.wojcieszak@pwr.edu.pl [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wrocław (Poland); Mazur, M.; Kaczmarek, D. [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wrocław (Poland); Mazur, P. [Institute of Experimental Physics, University of Wrocław, Max Born 9, 50-204 Wrocław (Poland); Szponar, B. [Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla 12, 53–114 Wrocław (Poland); Domaradzki, J. [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wrocław (Poland); Kepinski, L. [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okólna 2, 50-422 Wrocław (Poland)

    2016-05-01

    In this study the comparative investigations of structural, surface and bactericidal properties of Ti–Ag and Nb–Ag thin films have been carried out. Ti–Ag and Nb–Ag coatings were deposited on silicon and fused silica substrates by magnetron co-sputtering method using innovative multi-target apparatus. The physicochemical properties of prepared thin films were examined with the aid of X-ray diffraction, grazing incidence X-ray diffraction, scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy methods. Moreover, the wettability of the surface was determined. It was found that both, Ti–Ag and Nb–Ag thin films were nanocrystalline. In the case of Ag–Ti film presence of AgTi{sub 3} and Ag phases was identified, while in the structure of Nb–Ag only silver occurred in a crystal form. In both cases the average size of crystallites was ca. 11 nm. Moreover, according to scanning electron microscopy and atomic force microscopy investigations the surface of Nb–Ag thin films was covered with Ag-agglomerates, while Ti–Ag surface was smooth and devoid of silver particles. Studies of biological activity of deposited coatings in contact with Bacillus subtilis, Pseudomonas aeruginosa, Enterococcus hirae, Klebisiella pneumoniae, Escherichia coli, Staphylococcus aureus and Candida albicans were performed. It was found that prepared coatings were bactericidal and fungicidal even in a short term-contact, i.e. after 2 h. - Highlights: • Surface and biological properties of Ti–Ag and Nb–Ag thin films were examined. • Ag content was related to sputtering yields and nucleation of Ti and Nb. • For Nb–Ag film the agglomeration of silver at the surface was observed. • Composition and surface topography had an impact on antimicrobial properties. • Fine-grained surface was important in Ag ions release process.

  8. Influence of Annealing and UV Irradiation on Hydrophilicity of Ag-TiO Nanostructured Thin Films

    Directory of Open Access Journals (Sweden)

    Fanming Meng

    2012-01-01

    Full Text Available Ag-TiO2 nanostructured thin films with silver content of 5 vol% have been deposited on silicon, glass, and quartz substrates by RF magnetron sputtering and annealed in ambient air at 900°C for 15, 30, 60, 90, and 120 min. Their crystal structure, surface morphology, and hydrophilicity have been characterized by X-ray diffractometer, atomic force microscope, and water contact angle apparatus, respectively. The influence of annealing time and UV irradiation time on hydrophilic property of Ag-TiO2 thin films have been studied in detail. It is shown that annealing time influences crystal structure of Ag-TiO2 thin films. The unannealed film is amorphous and shows poor hydrophilicity. With the increase of annealing time from 15 to 120 min, the grain-size slowly increases and tends to uniformity. A suitable annealing time can significantly enhance the hydrophilic behavior of Ag-TiO2 films. Water contact angle decreases with the increase of irradiation time. The mechanism of hydrophilicity has been proposed and can be attributed to the increase of oxygen anion radicals O2− and reactive center of surface Ti3+.

  9. Influence of the surface properties on bactericidal and fungicidal activity of magnetron sputtered Ti-Ag and Nb-Ag thin films.

    Science.gov (United States)

    Wojcieszak, D; Mazur, M; Kaczmarek, D; Mazur, P; Szponar, B; Domaradzki, J; Kepinski, L

    2016-05-01

    In this study the comparative investigations of structural, surface and bactericidal properties of Ti-Ag and Nb-Ag thin films have been carried out. Ti-Ag and Nb-Ag coatings were deposited on silicon and fused silica substrates by magnetron co-sputtering method using innovative multi-target apparatus. The physicochemical properties of prepared thin films were examined with the aid of X-ray diffraction, grazing incidence X-ray diffraction, scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy methods. Moreover, the wettability of the surface was determined. It was found that both, Ti-Ag and Nb-Ag thin films were nanocrystalline. In the case of Ag-Ti film presence of AgTi3 and Ag phases was identified, while in the structure of Nb-Ag only silver occurred in a crystal form. In both cases the average size of crystallites was ca. 11 nm. Moreover, according to scanning electron microscopy and atomic force microscopy investigations the surface of Nb-Ag thin films was covered with Ag-agglomerates, while Ti-Ag surface was smooth and devoid of silver particles. Studies of biological activity of deposited coatings in contact with Bacillus subtilis, Pseudomonas aeruginosa, Enterococcus hirae, Klebisiella pneumoniae, Escherichia coli, Staphylococcus aureus and Candida albicans were performed. It was found that prepared coatings were bactericidal and fungicidal even in a short term-contact, i.e. after 2 h.

  10. Structural, optical and electronic properties of Ag-TiO2 nanocomposite thin film

    Science.gov (United States)

    Sharma, Himanshu; Singhal, R.; Siva Kumar, V. V.; Asokan, K.

    2016-12-01

    Nanocomposite thin films of Ag nanoparticles in TiO2 matrices were synthesised by RF magnetron co-sputtering and characterised by X-ray diffraction (XRD), Rutherford back scattering (RBS) spectrometry, UV-Vis, high-resolution transmission electron microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS). The composition of Ag was varied from 0 to 45 at.%. The thickness and the concentrations of Ag in the nanocomposite thin film were revealed by RBS. XRD analysis confirmed that the TiO2 matrix is in anatase phase and shows change in phase with Ag concentration. The UV-visible absorption spectroscopy revealed low-intense and broad surface plasmon resonance (SPR) peak at 500 nm for the thin film with 33 at.% Ag content that was red-shifted to 525 nm with increasing its intensity for 45 at.% of Ag. The red shift in SPR peak understood by Maxwell-Garnett theory and explained further nonexistence of SPR by interparticle separation from HR-TEM images and crystallinity. This HR-TEM image analysis confirmed the formation of Ag nanoparticles, and average radii were 5, 12, 15 nm. The Tauc plot reveals reduction in band gap from 3.05 to 2.25 eV with increase in Ag content. Above results are understood based on the XPS analysis which shows a strong interaction between the Ag nanoparticle and TiO2. This decrease in band gap was advantageous to enhance the properties like photocatalytic and bioactivities through SPR.

  11. Enhancement of light trapping in thin-film solar cells through Ag

    Institute of Scientific and Technical Information of China (English)

    Yiming Bai; Han Zhang; Jun Wang; Nuofu Chen; Jianxi Yao; Tianmao Huang; Xingwang Zhang; Zhigang Yin; Zhen Fu

    2011-01-01

    Forward-scattering efficiency (FSE) is first proposed when an Ag nanoparticle serves as the light-trapping structure for thin-film (TF) solar cells because the Ag nanoparticle's light-trapping efficiency lies on the light-scattering direction of metal nanoparticles. Based on FSE analysis of Ag nanoparticles with radii of 53 and 88 nm, the forward-scattering spectra and light-trapping efficiencies are calculated. The contributions of dipole and quadrupole modes to light-trapping effect are also analyzed quantitatively. When the surface coverage of Ag nanoparticles is 5%, light-trapping efficiencies are 15.5% and 32.3%, respectively, for 53- and 88-nm Ag nanoparticles. Results indicate that the plasmon quadrupole mode resonance of Ag nanoparticles could further enhance the light-trapping effect for TF solar cells.%@@ Forward-scattering efficiency (FSE) is first proposed when an Ag nanoparticle serves as the light-trapping structure for thin-film (TF) solar cells because the Ag nanoparticle's light-trapping efficiency lies on the light-scattering direction of metal nanoparticles.Based on FSE analysis of Ag nanoparticles with radii of 53 and 88 nm, the forward-scattering spectra and light-trapping efficiencies are calculated.The contributions of dipole and quadrupole modes to light-trapping effect are also analyzed quantitatively.When the surface coverage of Ag nanoparticles is 5%, light-trapping efficiencies are 15.5% and 32.3%, respectively, for 53- and 88-nm Ag nanoparticles.Results indicate that the plasmon quadrupole mode resonance of Ag nanoparticles could further enhance the light-trapping effect for TF solar cells.

  12. Preparation of AgInSe2 thin films grown by vacuum evaporation method

    Science.gov (United States)

    Matsuo, H.; Yoshino, K.; Ikari, T.

    2006-09-01

    Polycrystalline AgInSe2 thin films were successfully grown on glass substrates by an evaporation method. The starting materials were stoichiometrically mixed Ag2Se and In2Se3 powders. X-ray diffraction revealed that the sample annealed at 600 °C consisted of AgInSe2 single phase, with (112) orientation and a large grain size. The lattice constant (a axis) was close to JCPDS values. From optical transmittance and reflectance measurements, the bandgap energy was estimated to be 1.17 eV.

  13. 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....

  14. Aging and annealing effects on properties of Ag-N dual-acceptor doped ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Swapna, R.; Amiruddin, R.; Santhosh Kumar, M. C. [Advanced Materials Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli -620 015 (India)

    2013-02-05

    Ag-N dual acceptor doping into ZnO has been proposed to realize p-ZnO thin film of different concentrations (1, 2 and 4 at.%) by spray pyrolysis at 623 K and then 4 at.% films annealed at 673 K and 723 K for 1 hr. X-ray diffraction studies reveal that all the films are preferentially oriented along (002) plane. Energy dispersive spectroscopy (EDS) confirms the presence of Ag and N in 2 at.% ZnO:(Ag, N) film. Hall measurement shows that 4 at.% ZnO:(Ag, N) film achieved minimum resistivity with high hole concentration. The p-type conductivity of the ZnO:(Ag, N) films is retained even after 180 days. Photoluminescence (PL) spectra of ZnO:(Ag, N) films show low density of native defects.

  15. Investigation of AgInS{sub 2} thin films grown by coevaporation

    Energy Technology Data Exchange (ETDEWEB)

    Arredondo, C A; Gordillo, G [Departamento de Fisica, Universidad Nacional de Colombia, Bogota (Colombia); J, Clavijo, E-mail: caarredondoo@unal.edu.c, E-mail: ggordillog@unal.edu.c [Departamento de Quimica, Universidad Nacional de Colombia, Bogota, Cr.30 N0 45-03 (Colombia)

    2009-05-01

    AgInS{sub 2} thin films were grown on soda-lime glass substrates by co-evaporation of the precursors in a two-step process. X-ray diffraction (XRD) measurements indicated that these compounds grow in different phases and with different crystalline structure depending upon the deposition conditions. However, through a parameter study, conditions were found to grow thin films containing only the AgInS{sub 2} phase with chalcopyrite type structure. In samples containing a mixture of several phases, the contribution in percentage terms of each phase to the whole compound was estimated with the help of the PowderCell simulation package. It was also found that the AgInS{sub 2} films present p-type conductivity, a high absorption coefficient (greater than 10{sub 4} cm{sub -1}) and an energy band gap Eg of about 1.95 eV, indicating that this compound has good properties to perform as absorbent layer in thin film tandem solar cells. The effect of the deposition conditions on the optical and morphological properties was also investigated through spectral transmitance and atomic force microscopy (AFM) measurements.

  16. Atomic scale analysis of phase formation and diffusion kinetics in Ag/Al multilayer thin films

    Science.gov (United States)

    Aboulfadl, Hisham; Gallino, Isabella; Busch, Ralf; Mücklich, Frank

    2016-11-01

    Thin films generally exhibit unusual kinetics leading to chemical reactions far from equilibrium conditions. Binary metallic multilayer thin films with miscible elements show some similar behaviors with respect to interdiffusion and phase formation mechanisms. Interfacial density, lattice defects, internal stresses, layer morphologies and deposition conditions strongly control the mass transport between the individual layers. In the present work, Ag/Al multilayer thin films are used as a simple model system, in which the effects of the sputtering power and the bilayer period thickness on the interdiffusion and film reactions are investigated. Multilayers deposited by DC magnetron sputtering undergo calorimetric and microstructural analyses. In particular, atom probe tomography is extensively used to provide quantitative information on concentration gradients, grain boundary segregations, and reaction mechanisms. The magnitude of interdiffusion was found to be inversely proportional to the period thickness for the films deposited under the same conditions, and was reduced using low sputtering power. Both the local segregation at grain boundaries as well as pronounced non-equilibrium supersaturation effects play crucial roles during the early stages of the film reactions. For multilayers with small periods of 10 nm supersaturation of the Al layers with Ag precedes the polymorphic nucleation and growth of the hcp γ-Ag2Al phase. In larger periods the γ phase formation is triggered at junctions between grain boundaries and layers interfaces, where the pathway to heterogeneous nucleation is local supersaturation. Other Ag-rich phases also form as intermediate phases due to asymmetric diffusion rates of parent phases in the γ phase during annealing.

  17. Tailoring the structural and optical properties of TiN thin films by Ag ion implantation

    Science.gov (United States)

    Popović, M.; Novaković, M.; Rakočević, Z.; Bibić, N.

    2016-12-01

    Titanium nitride (TiN) thin films thickness of ∼260 nm prepared by dc reactive sputtering were irradiated with 200 keV silver (Ag) ions to the fluences ranging from 5 × 1015 ions/cm2 to 20 × 1015 ions/cm2. After implantation TiN layers were annealed 2 h at 700 °C in a vacuum. Ion irradiation-induced microstructural changes were examined by using Rutherford backscattering spectrometry, X-ray diffraction and transmission electron microscopy, while the surface topography was observed using atomic force microscopy. Spectroscopic ellipsometry was employed to get insights on the optical and electronic properties of TiN films with respect to their microstructure. The results showed that the irradiations lead to deformation of the lattice, increasing disorder and formation of new Ag phase. The optical results demonstrate the contribution of surface plasmon resonace (SPR) of Ag particles. SPR position shifted in the range of 354.3-476.9 nm when Ag ion fluence varied from 5 × 1015 ions/cm2 to 20 × 1015 ions/cm2. Shift in peak wavelength shows dependence on Ag particles concentration, suggesting that interaction between Ag particles dominate the surface plasmon resonance effect. Presence of Ag as second metal in the layer leads to overall decrease of optical resistivity of TiN.

  18. Antimicrobial effect of Al2O3, Ag and Al2O3/Ag thin films on Escherichia coli and Pseudomonas putida

    Science.gov (United States)

    Angelov, O.; Stoyanova, D.; Ivanova, I.; Todorova, S.

    2016-10-01

    The influence of Al2O3, Ag and Al2O3/Ag thin films on bacterial growth of Gramnegative bacteria Pseudomonas putida and Escherichia coli is studied. The nanostructured thin films are deposited on glass substrates without intentional heating through r.f. magnetron sputtering in Ar atmosphere of Al2O3 and Ag targets or through sequential sputtering of Al2O3 and Ag targets, respectively. The individual Ag thin films (thickness 8 nm) have a weak bacteriostatic effect on Escherichia coli expressed as an extended adaptive phase of the bacteria up to 5 hours from the beginning of the experiment, but the final effect is only 10 times lower bacterial density than in the control. The individual Al2O3 film (20 nm) has no antibacterial effect against two strains E. coli - industrial and pathogenic. The Al2O3/Ag bilayer films (Al2O3 20 nm/Ag 8 nm) have strong bactericidal effect on Pseudomonas putida and demonstrate an effective time of disinfection for 2 hours. The individual films Al2O3 and Ag have not pronounced antibacterial effect on Pseudomonas putida. A synergistic effect of Al2O3/Ag bilayer films in formation of oxidative species on the surface in contact with the bacterial suspension could be a reason for their antimicrobial effect on E. coli and P. putida.

  19. One step 'dip' and 'use' Ag nanostructured thin films for ultrahigh sensitive SERS Detection.

    Science.gov (United States)

    Rajkumar, Kanakaraj; Jayram, Naidu Dhanpal; Mangalaraj, Devanesan; Rajendra Kumar, Ramasamy Thangavelu

    2016-11-01

    A simple one step galvanic displacement method which involves dipping of the silicon substrate in the AgNO3/HF solution and using it for SERS application without any further process is demonstrated. The size and shape of the Ag nanoparticles changes as the deposition time is increased. Initially the shape of the particles was nearly spherical and as it grows, becomes oblong and then coalesce to form a discontinuous film with vertically grown hierarchical Ag nanostructures. The sizes of the deposited particles were in the ranges from 30nm to a discontinuous film. It also demonstrated a highly sensitive chemical detection by surface-enhanced Raman scattering of rhodamine 6G dye, down to 10(-16)M concentration. Prepared samples were able to detect lower concentrations of Melamine. Discontinuous thin films with hierarchical Ag nanostructures were obtained for 5min Ag deposition. The formation of Hot spots between the discontinuous islands and also along the hierarchical structures is responsible for the high SERS enhancement. This simple one step, fast, non-lithographic and cost effective method can be applied for various label free detection of analytes of importance.

  20. Morphology and N2 Permeance of Sputtered Pd-Ag Ultra-Thin Film Membranes

    Directory of Open Access Journals (Sweden)

    Ekain Fernandez

    2016-02-01

    Full Text Available The influence of the temperature during the growth of Pd-Ag films by PVD magnetron sputtering onto polished silicon wafers was studied in order to avoid the effect of the support roughness on the layer growth. The surfaces of the Pd-Ag membrane films were analyzed by atomic force microscopy (AFM, and the results indicate an increase of the grain size from 120 to 250–270 nm and film surface roughness from 4–5 to 10–12 nm when increasing the temperature from around 360–510 K. After selecting the conditions for obtaining the smallest grain size onto silicon wafer, thin Pd-Ag (0.5–2-µm thick films were deposited onto different types of porous supports to study the influence of the porous support, layer thickness and target power on the selective layer microstructure and membrane properties. The Pd-Ag layers deposited onto ZrO2 3-nm top layer supports (smallest pore size among all tested present high N2 permeance in the order of 10−6 mol·m−2·s−1·Pa−1 at room temperature.

  1. Effects of thermal annealing on the magnetic interactions in nanogranular Fe-Ag thin films

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, J.; Fdez-Gubieda, M.L.; Svalov, A. [Departamento de Electricidad y Electronica, Universidad del Pais Vasco (UPV/EHU), Campus de Leioa, 48940 Leioa (Spain); Meneghini, C. [Dipartimento di Fisica ' E. Amaldi' , Universita degli Studi Roma Tre, 00146 Roma (Italy); Orue, I. [SGIker, Universidad del Pais Vasco (UPV/EHU), Campus de Leioa, 48940 Leioa (Spain)

    2012-09-25

    Highlights: Black-Right-Pointing-Pointer Fe{sub x}Ag{sub 100-x} granular thin films with competing interactions (25 {<=} x{<=} 35). Black-Right-Pointing-Pointer Annealing up to 200 Degree-Sign C mainly modifies the interface of Fe nanoparticles. Black-Right-Pointing-Pointer Annealing reduces RKKY interactions in Fe{sub 25}Ag{sub 75}. Black-Right-Pointing-Pointer Annealing favors exchange interactions and ferromagnetic order in Fe{sub 35}Ag{sub 65}. - Abstract: In this paper we have studied, by analysing the evolution of the magnetic behaviour during thermal treatment, the role of the interparticle magnetic interactions in Fe{sub x}Ag{sub 100-x} granular thin films prepared by sputtering deposition technique. Two compositions have been selected: x = 25 and 35, below and around the magnetic percolation of the system, respectively, according to our previous works. The structure of these thin films has been studied by X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) measurements. To analyse the magnetic behaviour, DC magnetic measurements have been carried out after progressively annealing the samples at different temperatures (0 {<=} T{sub ann} {<=} 200 Degree-Sign C). These measurements have revealed that, upon thermal treatment, the frustrated state at low temperatures (T < 80 K) for the x = 25 sample tends to disappear, probably due to the weakening of RKKY interactions after the segregation of soluted Fe atoms in the Ag matrix. However, dipolar interactions are not affected by the annealing. On the contrary, at x = 35, around the magnetic percolation, the annealing gives rise to an increasingly ordered interface, thereby enhancing the transfer of the direct exchange interactions.

  2. Electrical and photoconductivity studies on AgSbSe2 thin films

    Science.gov (United States)

    Namitha Asokan, T.; Urmila, K. S.; Pradeep, B.

    2015-02-01

    Silver antimony selenide thin films have been deposited on ultrasonically cleaned glass substrate at a vacuum of 10-5 torr using reactive evaporation technique. The preparative parameters like substrate temperature and incident fluxes have been properly controlled in order to get highly reproducible compound films. The polycrystalline nature of the sample is confirmed using XRD. The dependence of the electrical conductivity on the temperature has also been studied. The prepared AgSbSe2 samples show p-type conductivity. The samples show a little photoresponse.

  3. Optical and electrical characterization of AgInS{sub 2} thin films deposited by spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Calixto-Rodriguez, M., E-mail: manuela@fis.unam.mx [Instituto de Ciencias Fisicas-Universidad Nacional Autonoma de Mexico, Apartado Postal 48-3, 62210, Cuernavaca, Morelos (Mexico); Martinez, H. [Instituto de Ciencias Fisicas-Universidad Nacional Autonoma de Mexico, Apartado Postal 48-3, 62210, Cuernavaca, Morelos (Mexico); Calixto, M.E. [Instituto de Fisica, Benemerita Universidad Autonoma de Puebla, Apartado Postal J-48, 72570, Puebla, Puebla (Mexico); Pena, Y. [Facultad de Ciencias Quimicas, Universidad Autonoma de Nuevo Leon, Pedro de Alba s/n, Ciudad Universitaria, 66451, San Nicolas de los Garza, Nuevo Leon (Mexico); Martinez-Escobar, Dalia [Centro de Investigacion en Energia-Universidad Nacional Autonoma de Mexico, 62580, Temixco, Morelos (Mexico); Tiburcio-Silver, A. [Instituto Tecnologico de Toluca-SEP, Apartado Postal 20, 52176, Metepec 3, Estado de Mexico (Mexico); Sanchez-Juarez, A. [Centro de Investigacion en Energia-Universidad Nacional Autonoma de Mexico, 62580, Temixco, Morelos (Mexico)

    2010-10-25

    Silver indium sulfide (AgInS{sub 2}) thin films have been prepared by spray pyrolysis (SP) technique using silver acetate, indium acetate, and N, N-dimethylthiourea as precursor compounds. Films were deposited onto glass substrates at different substrate temperatures (T{sub s}) and Ag:In:S ratios in the starting solutions. Optical transmission and reflection as well as electrical measurements were performed in order to study the effect of deposition parameters on the optical and electrical properties of AgInS{sub 2} thin films. X-ray diffraction measurements were used to identify the deposited compounds. It was found that different compounds such as AgInS{sub 2}, Ag{sub 2}S, In{sub 2}O{sub 3}, and In{sub 2}S{sub 3} can be grown only by changing the Ag:In:S ratio in the starting solution and T{sub s}. So that, by carefully selecting the deposition parameters, single phase AgInS{sub 2} thin films can be easily grown. Thin films obtained using a molar ratio of Ag:In:S = 1:1:2 and T{sub s} = 400 {sup o}C, have an optical band gap of 1.9 eV and n-type electrical conductivity with a value of 0.3 {Omega}{sup -1} cm{sup -1} in the dark.

  4. Structuring of DLC:Ag nanocomposite thin films employing plasma chemical etching and ion sputtering

    Science.gov (United States)

    Tamulevičius, Tomas; Tamulevičienė, Asta; Virganavičius, Dainius; Vasiliauskas, Andrius; Kopustinskas, Vitoldas; Meškinis, Šarūnas; Tamulevičius, Sigitas

    2014-12-01

    We analyze structuring effects of diamond like carbon based silver nanocomposite (DLC:Ag) thin films by CF4/O2 plasma chemical etching and Ar+ sputtering. DLC:Ag films were deposited employing unbalanced reactive magnetron sputtering of silver target with Ar+ in C2H2 gas atmosphere. Films with different silver content (0.6-12.9 at.%) were analyzed. The films (as deposited and exposed to plasma chemical etching) were characterized employing scanning electron microscopy and energy dispersive X-ray analysis (SEM/EDS), optical microscopy, ultraviolet-visible light (UV-VIS) spectroscopy and Fourier transform infrared (FTIR) spectroscopy. After deposition, the films were plasma chemically etched in CF4/O2 mixture plasma for 2-6 min. It is shown that optical properties of thin films and silver nano particle size distribution can be tailored during deposition changing the magnetron current and C2H2/Ar ratio or during following plasma chemical etching. The plasma etching enabled to reveal the silver filler particle size distribution and to control silver content on the surface that was found to be dependent on Ostwald ripening process of silver nano-clusters. Employing contact lithography and 4 μm period mask in photoresist or aluminum the films were patterned employing CF4/O2 mixture plasma chemical etching, direct Ar+ sputtering or combined etching processes. It is shown that different processing recipes result in different final grating structures. Selective carbon etching in CF4/O2 gas mixture with photoresist mask revealed micrometer range lines of silver nanoparticles, while Ar+ sputtering and combined processing employing aluminum mask resulted in nanocomposite material (DLC:Ag) micropatterns.

  5. Absorption Spectra and Ionic Conductivity of RbxCs1-xAg4I5 Superionic Conductors Thin Films

    Institute of Scientific and Technical Information of China (English)

    CAO Yang; SUN Jia-Lin; ZHANG Guo-Sheng; GUO Ji-Hua; WANG Zheng-Ping

    2005-01-01

    @@ A series of RbxCs1-xAg4I5 (x = 0-1) thin films were grown by vacuum evaporation on NaCl crystal substratesat 350K. The absorption spectra of these films were measured at 80 K in the wavelength range from 240nm to 400nm. It is shown that superionic conductor thin films of quaternary compound Rb0.5Cs0.5Ag4I5 and ternarycompound RbAg4I5 can be obtained at x = 0.5-0.6 and x = 0.7-1, respectively. At x = 0.65, the combinedcompound film of the mixture of 30mol% RbAg4I5 and 70mol% Rb0.5Cs0.5Ag4I5 is presented. Then, based on the spectral positions of the A1 and A2 peaks, we determined that the Rb0.5Cs0.5Ag4I5 exciton coupling energy Rex is 0.21 eV, the forbidden zone width Eg is 3.82eV and the exciton radius aex is 0.70nm. Furthermore, the ionic conductivities of superionic conductor thin films of RbAg4I5 and Rb0.5Cso.5Ag4I5 and their mixture film are investigated, respectively, in the temperature range 303 K-393 K.

  6. Single-pulse transformation of Ag thin film into nanoparticles via laser-induced dewetting

    Science.gov (United States)

    Oh, Yoonseok; Lee, Myeongkyu

    2017-03-01

    In this study, we show that Ag thin films deposited on glass can be transformed into nanoparticles by laser-induced dewetting using a nanosecond-pulsed Nd:YAG laser. The film could be completely dewetted by a single pulse and the pulse energy density required for a 10 nm-thick Ag film was 86 mJ/cm2 at λ = 1064 nm. This made it possible to dewet a film area of ∼10 cm2 by a single pulse with energy of 850 mJ. The produced particles exhibited a monomodal size distribution and the mean particle size increased as the initial film thickness increased. Repeated exposure to pulses induced no noticeable change in the particle size distribution. The initial film thickness was the only factor that determined the mean particle size. The absorption spectra of dewetted films were well consistent with the surface plasma resonance behaviors of metal nanoparticles. This process provides a facile and scalable method of forming metal nanoparticle arrays for plasmonic and other applications.

  7. Synthesis of Ag-TiO2 composite nano thin film for antimicrobial application

    Science.gov (United States)

    Yu, Binyu; Leung, Kar Man; Guo, Qiuquan; Lau, Woon Ming; Yang, Jun

    2011-03-01

    TiO2 photocatalysts have been found to kill cancer cells, bacteria and viruses under mild UV illumination, which offers numerous potential applications. On the other hand, Ag has long been proved as a good antibacterial material as well. The advantage of Ag-TiO2 nanocomposite is to expand the nanomaterial's antibacterial function to a broader range of working conditions. In this study neat TiO2 and Ag-TiO2 composite nanofilms were successfully prepared on silicon wafer via the sol-gel method by the spin-coating technique. The as-prepared composite Ag-TiO2 and TiO2 films with different silver content were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) to determine the topologies, microstructures and chemical compositions, respectively. It was found that the silver nanoparticles were uniformly distributed and strongly attached to the mesoporous TiO2 matrix. The morphology of the composite film could be controlled by simply tuning the molar ratio of the silver nitrate aqueous solution. XPS results confirmed that the Ag was in the Ag0 state. The antimicrobial effect of the synthesized nanofilms was carried out against gram-negative bacteria (Escherichia coli ATCC 29425) by using an 8 W UV lamp with a constant relative intensity of 0.6 mW cm - 2 and in the dark respectively. The synthesized Ag-TiO2 thin films showed enhanced bactericidal activities compared to the neat TiO2 nanofilm both in the dark and under UV illumination.

  8. Synthesis of Ag-TiO2 composite nano thin film for antimicrobial application.

    Science.gov (United States)

    Yu, Binyu; Leung, Kar Man; Guo, Qiuquan; Lau, Woon Ming; Yang, Jun

    2011-03-18

    TiO2 photocatalysts have been found to kill cancer cells, bacteria and viruses under mild UV illumination, which offers numerous potential applications. On the other hand, Ag has long been proved as a good antibacterial material as well. The advantage of Ag-TiO2 nanocomposite is to expand the nanomaterial's antibacterial function to a broader range of working conditions. In this study neat TiO2 and Ag-TiO2 composite nanofilms were successfully prepared on silicon wafer via the sol-gel method by the spin-coating technique. The as-prepared composite Ag-TiO2 and TiO2 films with different silver content were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) to determine the topologies, microstructures and chemical compositions, respectively. It was found that the silver nanoparticles were uniformly distributed and strongly attached to the mesoporous TiO2 matrix. The morphology of the composite film could be controlled by simply tuning the molar ratio of the silver nitrate aqueous solution. XPS results confirmed that the Ag was in the Ag(0) state. The antimicrobial effect of the synthesized nanofilms was carried out against gram-negative bacteria (Escherichia coli ATCC 29425) by using an 8 W UV lamp with a constant relative intensity of 0.6 mW cm(-2) and in the dark respectively. The synthesized Ag-TiO2 thin films showed enhanced bactericidal activities compared to the neat TiO2 nanofilm both in the dark and under UV illumination.

  9. Synthesis of Ag-TiO{sub 2} composite nano thin film for antimicrobial application

    Energy Technology Data Exchange (ETDEWEB)

    Yu Binyu; Guo Qiuquan; Yang Jun [Biomedical Engineering Graduate Program, University of Western Ontario, London, ON, N6A 5B9 (Canada); Leung, Kar Man [Department of Mechanical and Materials Engineering, University of Western Ontario, London, ON, N6A 5B9 (Canada); Lau, Woon Ming [Surface Science Western, University of Western Ontario, London, ON, N6A 5B9 (Canada)

    2011-03-18

    TiO{sub 2} photocatalysts have been found to kill cancer cells, bacteria and viruses under mild UV illumination, which offers numerous potential applications. On the other hand, Ag has long been proved as a good antibacterial material as well. The advantage of Ag-TiO{sub 2} nanocomposite is to expand the nanomaterial's antibacterial function to a broader range of working conditions. In this study neat TiO{sub 2} and Ag-TiO{sub 2} composite nanofilms were successfully prepared on silicon wafer via the sol-gel method by the spin-coating technique. The as-prepared composite Ag-TiO{sub 2} and TiO{sub 2} films with different silver content were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) to determine the topologies, microstructures and chemical compositions, respectively. It was found that the silver nanoparticles were uniformly distributed and strongly attached to the mesoporous TiO{sub 2} matrix. The morphology of the composite film could be controlled by simply tuning the molar ratio of the silver nitrate aqueous solution. XPS results confirmed that the Ag was in the Ag{sup 0} state. The antimicrobial effect of the synthesized nanofilms was carried out against gram-negative bacteria (Escherichia coli ATCC 29425) by using an 8 W UV lamp with a constant relative intensity of 0.6 mW cm{sup -2} and in the dark respectively. The synthesized Ag-TiO{sub 2} thin films showed enhanced bactericidal activities compared to the neat TiO{sub 2} nanofilm both in the dark and under UV illumination.

  10. Formation of nanodots and enhancement of thermoelectric power induced by ion irradiation in PbTe:Ag composite thin films

    Energy Technology Data Exchange (ETDEWEB)

    Bala, Manju, E-mail: manjubala474@gmail.com [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Meena, Ramcharan; Gupta, Srashti; Pannu, Compesh [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Tripathi, Tripurari S. [Aalto University, Värmemansgränden 2, 02150 Espoo (Finland); Varma, Shikha [Institute of Physics, Bhubaneshwar, Odisha 751005 (India); Tripathi, Surya K. [Department of Physics, Panjab University, Chandigarh 160 014 (India); Asokan, K., E-mail: asokaniuac@gmail.com [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Avasthi, Devesh K. [Amity University, Noida 201313, Uttar Pradesh (India)

    2016-07-15

    Present study demonstrates an enhancement in thermoelectric power of 10% Ag doped PbTe (PbTe:Ag) thin films when irradiated with 200 keV Ar ion. X-ray diffraction showed an increase in crystallinity for both PbTe and PbTe:10Ag nano-composite films after Ar ion irradiation due to annealing of defects in the grain boundaries. The preferential sputtering of Pb and Te ions in comparison to Ag ions resulted in the formation of nano-dots. This was further confirmed by X-ray photoelectron spectroscopy (XPS). Such an enhancement in thermoelectric power of irradiated PbTe:10Ag films in comparison to pristine PbTe:10Ag film is attributed to the decrease in charge carrier concentration that takes part in the transport process via restricting the tunneling of carriers through the wider potential barrier formed at the interface of nano-dots.

  11. Preparation of nano-Ag/TiO2 thin-film

    Institute of Scientific and Technical Information of China (English)

    PENG Bing; WANG Jia; CHAI Li-yuan; MAO Ai-li; WANG Yun-yan

    2008-01-01

    Steady TiO2 water-sol was prepared by peptization and the effects of pH value, temperature, concentration of colloid and peptizator on sol were investigated. Laser grain analyzer was used to verify nano-particles in the sol. The photocatalytic degradation ratio and antibacterial property of nano-Ag/TiO2 thin-film on ceramics were used as the main index in addition to XRD analysis. The effect of film layers, embedding Ag+, annealing temperature and time on the degradation ratio and antibacterial property was studied. The temperature 30-80 ℃, pH 1.2-2.0, concentrations of 0.05-0.3 mol/L sol and 5% HNO3 would be the optimal parameters for the TiO2 water-sol preparation. The nano-Ag/TiO2 film of three layers with 3% AgNO3 embedded and treated at 350 ℃ for 2 h exhibits good performance. The elementary research on the kinetics of degradation shows that the reactions are on the first order kinetics equation.

  12. Optical and structural properties of Cr and Ag thin films deposited on glass substrate

    Science.gov (United States)

    Rauf, A.; Ahmed, K.; Nasim, F.; Khan, A. N.; Gul, A.

    2016-08-01

    Most of the rotating or noting patterns are being developed by using silver plating through chemical coating. Silver layers deteriorate with the passage of time and become less reflective while undergo through cleaning process due to its softness and the results become unpredictable. In this paper an alternate method for development of above mentioned pattern has been demonstrated. Chromium (Cr) and Silver (Ag) thin films of 200nm and 160nm thick respectively have been realized using electron beam evaporation (PVD technique) on quartz substrate. Structural analysis has been carried out by XRD and SEM while optical transmission/reflection has been studied using spectrophotometer. XRD analysis shows that Ag coated thin films exhibit FCC structure while Cr coated thin films reveals a BCC structure. SEM analysis shows almost smooth and uniform surfaces in both cases. After passing through high and low temperature cycles it was found that the results of pattern structures developed by chromium coating were more reliable than obtained through silver platting process.

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

    Energy Technology Data Exchange (ETDEWEB)

    Nazir, Adnan, E-mail: adnan.nazir@iit.it [Istituto Italiano di Tecnologia, Via Morego 30, I-16163 Genova (Italy); School of Chemical and Materials Engineering, National University of Sciences and Technology, Islamabad (Pakistan); Toma, Andrea [Istituto Italiano di Tecnologia, Via Morego 30, I-16163 Genova (Italy); Shah, Nazar Abbas [Department of Physics, COMSATS Institute of Information Technology, Islamabad (Pakistan); Panaro, Simone [Istituto Italiano di Tecnologia, Via Morego 30, I-16163 Genova (Italy); Butt, Sajid [Department of Materials Science and Engineering, Institute of Space Technology (IST), Islamabad 44000 (Pakistan); School of Chemical and Materials Engineering, National University of Sciences and Technology, Islamabad (Pakistan); Sagar, Rizwan ur Rehman [Department of Physics, COMSATS Institute of Information Technology, Islamabad (Pakistan); Raja, Waseem [Istituto Italiano di Tecnologia, Via Morego 30, I-16163 Genova (Italy); Rasool, Kamran [Micro and Nano Devices Group, Department of Metallurgy and Materials Engineering Pakistan, Institute of Engineering and Applied Sciences (PIEAS), P.O. Nilore, Islamabad 45650 (Pakistan); Maqsood, Asghari [Department of Physics, Air University, Islamabad (Pakistan)

    2014-10-01

    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{sup 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{sup 3} Ω cm) against a 20% cut in optical transmission.

  14. Structural analysis of TiO2 and TiO2-Ag thin films and their antibacterial behaviors

    Science.gov (United States)

    Hsieh, J. H.; Yu, R. B.; Chang, Y. K.; Li, C.

    2012-01-01

    TiO2 (rutile and anatase) thin films was first prepared using reactive sputtering, in an Ar+O2 plasma. In the 2nd stage of the experiment, various amounts (3, 7, and 10 at. %) of Ag was doped into the rutile film in order to form TiO2-Ag thin films. These films were annealed for one hour in Ar atmosphere, at 300, 400, and 500 °C. The films' structures were then examined using X-ray diffractometry. FESEM (field-emission scaning electron microscopy) was used to investigate the surface emergence of Ag particles. As for the examination of optical band gaps and absorption of these films, UV-Vis-NIR photometer was used. The results show that, in as-deposited condition, the addition of Ag might disrupt the growth of crystalline structure and cause the formation of amorphous films. After annealing, it is found that the structure tends to become anatase phase which is a metastable phase between amorphous titanium oxide and rutile. More importantly, the absorption of the Ag-doped films would be enhanced in the visible-light range. Some of the enhancement is clearly due to plasmon resonance effect. The Ag-doped samples have shown some antibacterial effect in dark. When irradiated with light, the samples show a synergistic behavior combining the bactericidal effect of Ag ions and photocatalytic effect of TiO2.

  15. The effect of different annealing conditions in undoped and Ag doped ZnO thin films grown by SILAR method

    OpenAIRE

    GÜNEY, HARUN

    2015-01-01

    Undoped, %3 and %5 Silver (Ag) doped zinc oxide (ZnO) thin films have been grown on glass substrates by simple and economic successive ionic layer absorption and reaction method (SILAR). All grown films were annealed vacuum and air to investigate to effective annealing at 573 K for 30 minutes. Energy-Dispersive-X-Ray-Fluorescence (EDXRF) spectroscopy showed %3 and %5 dopants Ag. Absorbance measurements showed that the optical band-gaps of all thin films were wide and generally decrease with a...

  16. Hybrid AgNP–TiO2 thin film based photoanode for dye sensitized solar cell

    Directory of Open Access Journals (Sweden)

    Jayraj V. Vaghasiya

    2016-09-01

    Full Text Available This article addresses two major issues in the plasmonic dye solar cell; (i protection of plasmonic nanoparticles from electrolyte attack and (ii design of appropriate molecular dye to harvest photon near the plasmonic resonance. This report reveals the synthesis of D-π-A carbazole dye and incorporation of plasmonic Ag nanoparticles (AgNPs into TiO2 film using Ag–TiO2 gel. We have designed and synthesized an efficient D-π-A carbazole dye molecule whose absorption maxima matches the plasmonic resonance of AgNPs leading to augmented near field effect, enhancing photon harvesting property of dye molecule. This article also describes a strategy to incorporate AgNPs into the TiO2 photoelectrode by Ag–TiO2 gel. The plasmonic photoanode was characterized using SEM and optical spectroscopy. Dye solar cells were characterized by J–V characteristics and electrochemical impedance technique in order to take insight into photovoltaic performance and electron transfer kinetic. This engineered DSSC achieves 45% enhancement in current due to the plasmon enhanced near field effect at thin film (3 μm.

  17. Microwave sintering of Ag-nanoparticle thin films on a polyimide substrate

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, S., E-mail: fujii.s.ap@m.titech.ac.jp [Department of Applied Chemistry, Tokyo Institute of Technology, Tokyo 152-8522 (Japan); Department of Information and Communication System Engineering, National Institute of Technology, Okinawa College, Nago, Okinawa 905-2192 (Japan); Kawamura, S.; Maitani, M. M.; Suzuki, E.; Wada, Y. [Department of Applied Chemistry, Tokyo Institute of Technology, Tokyo 152-8522 (Japan); Mochizuki, D. [Interdisciplinary Cluster for Cutting Edge Research, Center for Energy and Environmental Science, Shinshu University, Ueda, Nagano 386-8567 (Japan)

    2015-12-15

    Ag-nanoparticle thin films on a polyimide substrate were subjected to microwave sintering by use of a single-mode waveguide applicator. A two-step sintering process was employed. First, at low conductivities of the film, the film sample was placed at the site of the maximum electric field and subjected to microwave irradiation. Second, when the conductivity of the film increased, the film sample was placed at the site of the maximum magnetic field and again subjected to microwave irradiation. The microwave sintering process was completed within 1.5 min, which is significantly lower than the time required for the oven heating process. The resulting conductivity of the film, albeit only 30% of that of the bulk material, was seven times that of a film annealed at the same temperature in a furnace. Scanning electron microscopy images revealed that the nanoparticles underwent both grain necking and grain growth during microwave sintering. In addition, this sintering process was equivalent to the oven heating process performed at a 50 °C higher annealing temperature. An electromagnetic wave simulation and a heat transfer simulation of the microwave sintering process were performed to gain a thorough understanding of the process.

  18. Microwave sintering of Ag-nanoparticle thin films on a polyimide substrate

    Directory of Open Access Journals (Sweden)

    S. Fujii

    2015-12-01

    Full Text Available Ag-nanoparticle thin films on a polyimide substrate were subjected to microwave sintering by use of a single-mode waveguide applicator. A two-step sintering process was employed. First, at low conductivities of the film, the film sample was placed at the site of the maximum electric field and subjected to microwave irradiation. Second, when the conductivity of the film increased, the film sample was placed at the site of the maximum magnetic field and again subjected to microwave irradiation. The microwave sintering process was completed within 1.5 min, which is significantly lower than the time required for the oven heating process. The resulting conductivity of the film, albeit only 30% of that of the bulk material, was seven times that of a film annealed at the same temperature in a furnace. Scanning electron microscopy images revealed that the nanoparticles underwent both grain necking and grain growth during microwave sintering. In addition, this sintering process was equivalent to the oven heating process performed at a 50 °C higher annealing temperature. An electromagnetic wave simulation and a heat transfer simulation of the microwave sintering process were performed to gain a thorough understanding of the process.

  19. Speciation and Lability of Ag-, AgCl- and Ag2S-Nanoparticles in Soil Determined by X-ray Absorption Spectroscopy and Diffusive Gradients in Thin Films

    Science.gov (United States)

    Long-term speciation and lability of silver (Ag-), silver chloride (AgCl-) and silver sulfide nanoparticles (Ag2S-NPs) in soil were studied by X-ray absorption spectroscopy (XAS), and newly developed "nano" Diffusive Gradients in Thin Films (DGT) devices. These nano-D...

  20. Preparation and characterization of double layer thin films ZnO/ZnO:Ag for methylene blue photodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Wibowo, Singgih, E-mail: singgih@st.fisika.undip.ac.id; Sutanto, Heri, E-mail: herisutanto@undip.ac.id [Department of Physics, Faculty of Science and Mathematics, Diponegoro University (Indonesia)

    2016-02-08

    Double layer (DL) thin films of zinc oxide and silver-doped zinc oxide (ZnO/ZnO:Ag) were deposited on glass substrate by sol-gel spray coating technique. The prepared thin films were subjected for optical and photocatalytic studies. UV-visible transmission spectra shows that the subtitution of Ag in ZnO leads to band gap reduction. The influence of Ag doping on the photocatalytic activity of ZnO for the degradation of methylene blue dye was studied under solar radiation. The light absorption over an extended visible region by Ag ion doping in ZnO film contributed equally to improve the photocatalytic activity up to 98.29%.

  1. Preparation and characterization of double layer thin films ZnO/ZnO:Ag for methylene blue photodegradation

    Science.gov (United States)

    Wibowo, Singgih; Sutanto, Heri

    2016-02-01

    Double layer (DL) thin films of zinc oxide and silver-doped zinc oxide (ZnO/ZnO:Ag) were deposited on glass substrate by sol-gel spray coating technique. The prepared thin films were subjected for optical and photocatalytic studies. UV-visible transmission spectra shows that the subtitution of Ag in ZnO leads to band gap reduction. The influence of Ag doping on the photocatalytic activity of ZnO for the degradation of methylene blue dye was studied under solar radiation. The light absorption over an extended visible region by Ag ion doping in ZnO film contributed equally to improve the photocatalytic activity up to 98.29%.

  2. The effects of deposition time on surface morphology, structural, electrical and optical properties of sputtered Ag-Cu thin films

    Science.gov (United States)

    Ahmadpourian, Azin; Luna, Carlos; Boochani, Arash; Arman, Ali; Achour, Amine; Rezaee, Sahare; Naderi, Sirvan

    2016-10-01

    The preparation of designed nanostructured thin films combining nano grains of different compositions and physical properties represents a promising avenue for the exploration of novel collective behaviors with technological potentials. Herein, nanostructured Ag-Cu thin films with different surface morphology properties were grown by magnetron sputtering varying the deposition time (4-24 min) and fixing the other deposition conditions. X-ray diffraction studies corroborated that Cu and Ag tend to appear as separated phases with nanometric sizes due to the fact that these elements are rather immiscible. The deposited Cu tended to be partially oxidized with crystal sizes of several tens of nm, whereas the deposited Ag phase displayed a poor crystallinity with an average crystal size of around 3nm. However, at deposition time of few minutes, the formation of Ag-Cu crystals with a preferable crystallization orientation along the [111] direction was detected. The surface morphology of the obtained thin films was studied by atomic force microscopy determining the surface roughness and average particle sizes of the samples. These parameters were correlated with the plasmon resonance extinction bands of the different Ag-Cu films and their electrical properties, providing a reproducible route to obtain thin films with tuned electrical resistances and optical properties.

  3. Optical and water repellant properties of Ag/SnO2 bilayer thin films

    Directory of Open Access Journals (Sweden)

    Ravipati Praveena

    2016-02-01

    Full Text Available The optical and water repellant properties of single layer and bilayer films of Ag and SnO2 deposited on glass substrates by thermal evaporation have been reported. Ag/SnO2 bilayers were deposited in two sequences wherein the deposition of SnO2 layer was followed by Ag deposition and vice versa. X-ray diffraction studies show that the Ag films crystallize in the FCC structure and SnO2 is amorphous, while atomic force microscopy images indicate the formation of large clusters of the order of 12 nm. The single layer Ag films exhibit localized surface plasmon resonance (LSPR that shifts from visible region to the infrared with increase in thickness from 5 to 12 nm. It is observed that, only the Ag films of thickness ≤ 8 nm exhibits LSPR peak whereas the critical thickness is 5 nm for Ag/SnO2 films. A blue shift is observed in the LSPR peak position when the SnO2 layer caps the Ag film. Whereas, the LSPR of Ag is suppressed significantly when the SnO2 layer is introduced between the glass and the Ag film and also when Ag and SnO2 were co-evaporated. Water repellant properties indicate that the pure Ag film has an average contact angle of 104o which decreases to 100o when SnO2 caps the Ag layer and 97o when Ag is deposited on top of the SnO2 buffer layer. Co-evaporated Ag-SnO2 films show a contact angle of 93o.

  4. Theory and practical considerations of multilayer dielectric thin-film stacks in Ag-coated hollow waveguides.

    Science.gov (United States)

    Bledt, Carlos M; Melzer, Jeffrey E; Harrington, James A

    2014-02-01

    This analysis explores the theory and design of dielectric multilayer reflection-enhancing thin film stacks based on high and low refractive index alternating layers of cadmium sulfide (CdS) and lead sulfide (PbS) on silver (Ag)-coated hollow glass waveguides (HGWs) for low loss transmission at midinfrared wavelengths. The fundamentals for determining propagation losses in such multilayer thin-film-coated Ag hollow waveguides is thoroughly discussed, and forms the basis for further theoretical analysis presented in this study. The effects on propagation loss resulting from several key parameters of these multilayer thin film stacks is further explored in order to bridge the gap between results predicted through calculation under ideal conditions and deviations from such ideal models that often arise in practice. In particular, the effects on loss due to the number of dielectric thin film layers deposited, deviation from ideal individual layer thicknesses, and surface roughness related scattering losses are presented and thoroughly investigated. Through such extensive theoretical analysis the level of understanding of the underlying loss mechanisms of multilayer thin-film Ag-coated HGWs is greatly advanced, considerably increasing the potential practical development of next-generation ultralow-loss mid-IR Ag/multilayer dielectric-coated HGWs.

  5. Chemically deposited In2S3-Ag2S layers to obtain AgInS2 thin films by thermal annealing

    Science.gov (United States)

    Lugo, S.; Peña, Y.; Calixto-Rodriguez, M.; López-Mata, C.; Ramón, M. L.; Gómez, I.; Acosta, A.

    2012-12-01

    AgInS2 thin films were obtained by the annealing of chemical bath deposited In2S3-Ag2S layers at 400 °C in N2 for 1 h. According to the XRD and EDX results the chalcopyrite structure of AgInS2 has been obtained. These films have an optical band gap, Eg, of 1.86 eV and an electrical conductivity value of 1.2 × 10-3 (Ω cm)-1.

  6. Photocatalytic Activity of Vis-Responsive Ag-Nanoparticles/TiO2 Composite Thin Films Fabricated by Molecular Precursor Method (MPM

    Directory of Open Access Journals (Sweden)

    Mitsunobu Sato

    2013-07-01

    Full Text Available The Ag-nanoparticles (Ag-NP/TiO2 composite thin films with various amounts of Ag (10 mol% ≤ n ≤ 80 mol% were examined as a potential photocatalyst by decoloration reaction of methylene blue (MB in an aqueous solution. These composite thin films of ca. 100 nm thickness were fabricated by the MPM at 600 °C in air. The decoloration rates monitored by the absorption intensity of the MB solution indicated that the composite thin films of Ag with an amount less than 40 mol% are not effective under vis-irradiation, though they can work as a photocatalyst under UV-irradiation. Further, the UV-sensitivity of the composite thin films gradually decreased to almost half the level of that of the TiO2 thin film fabricated under the identical conditions when the Ag amount increased from 10 to 40 mol%. Contrarily, the composite thin films of Ag content larger than 50 mol% showed the vis-responsive activity, whose level was slightly lower than the decreased UV-sensitivity. Diffuse reflectance spectra suggested that the vis-responsive activity of the composite thin films is due to the conductivity, localized surface plasmon resonance and surface plasmon resonance of Ag-NP. It was also elucidated that the vis-responsive level of the composite thin films corresponds to their electrical conductivity that depends on the Ag content.

  7. A dry method to synthesize dendritic Ag2Se nanostructures utilizing CdSe quantum dots and Ag thin films

    Science.gov (United States)

    Hu, Lian; Zhang, Bingpo; Xu, Tianning; Li, Ruifeng; Wu, Huizhen

    2015-01-01

    Dendritic Ag2Se nanostructures are synthesized in a dry environment by UV irradiating the hybrids composed of CdSe quantum dots (QDs) and silver (Ag). UV irradiation on CdSe QDs induces a photooxidation effect on the QD surface and leads to the formation of SeO2 components. Then SeO2 reacts with the Ag atoms in either Ag film or QD layer to produce the Ag2Se. The growth mechanism of Ag2Se dendrites on solid Ag films is explored and explained by a diffusion limited aggregation model in which the QD layer provides enough freedom for Ag2Se motion. Since the oxidation of the CdSe QDs is the critical step for the Ag2Se dendrites formation this dry chemical interaction between QDs and Ag film can be applied in the study of the QD surface chemical properties. With this dry synthesis method, the Ag2Se dendrites can also be facilely formed at the designed area on Ag substrates.

  8. On the optical properties of wedge-shaped thin films of Ag-photodoped As 30S 70 glass

    Science.gov (United States)

    Márquez, E.; Ramirez-Malo, J. B.; Fernández-Peña, J.; Jiménez-Garay, R.; Ewen, P. J. S.; Owen, A. E.

    1993-07-01

    Thin films of a-As 30S 70 prepared by thermal evaporation were photodoped with Ag. The optical transmission was measured over the 0.3 to 2.0 μm spectral region in order to derive the refractive index and absorption coefficient of these Ag-photodoped chalcogenide films. Furthermore, the analytical expressions proposed by Swanepoel, enabling the calculation of the optical constants of a thin film with non-uniform thickness, have successfully been applied. In addition, thickness measurements made by a surface-profiling stylus were also carried out to cross-check the results corresponding to the envelope method. On the other hand, the dispersion of n was discussed in terms of the single-oscillator Wemple and DiDomencio model. Finally, the value of the optical band gap decreased from 2.47 eV in the case of the undoped films down to 1.91 eV in the almost saturated Ag-photodoped films. It is plausible that the decrease in Eoptg by the incorporation of Ag arises from the smaller binding energy of Ag-S and As-As bonds compared to that of As-S bonds.

  9. Thickness Dispersion of Surface Plasmon of Ag Nano-thin Films: Determination by Ellipsometry Iterated with Transmittance Method

    Science.gov (United States)

    Gong, Junbo; Dai, Rucheng; Wang, Zhongping; Zhang, Zengming

    2015-03-01

    Effective optical constants of Ag thin films are precisely determined with effective thickness simultaneously by using an ellipsometry iterated with transmittance method. Unlike the bulk optical constants in Palik's database the effective optical constants of ultrathin Ag films are found to strongly depend on the thickness. According to the optical data two branches of thickness dispersion of surface plasmon energy are derived and agreed with theoretical predication. The thickness dispersion of bulk plasmon is also observed. The influence of substrate on surface plasmon is verified for the first time by using ellipsometry. The thickness dependent effective energy loss function is thus obtained based on this optical method for Ag ultrathin films. This method is also applicable to other ultrathin films and can be used to establish an effective optical database for ultrathin films.

  10. Crystal and electronic structure study of AgAu and AgCu bimetallic alloy thin films by X-ray techniques

    Energy Technology Data Exchange (ETDEWEB)

    Ozkendir, O. Murat, E-mail: ozkendir@gmail.com [Mersin University, Faculty of Technology, Energy Systems Engineering, Tarsus (Turkey); Mersin University, Institute of Natural Science, Department of Nanotechnology and Advanced Materials, Mersin (Turkey); Cengiz, E. [Karadeniz Technical University, Faculty of Science, Department of Physics, Trabzon (Turkey); Yalaz, E. [Mersin University, Institute of Natural Science, Department of Nanotechnology and Advanced Materials, Mersin (Turkey); Söğüt, Ö.; Ayas, D.H. [Kahramanmaraş Sütçü İmam Üniversitesi, Faculty of Science and Letters, Department of Physics, Kahramanmaraş (Turkey); Thammajak, B. Nirawat [Synchrotron Light Research Institute (Public Organisation), 111 University Avenue, T. Suranaree, A. Muang, Nakhon Ratchasima 30000 (Thailand)

    2016-05-15

    Highlights: • Crystal and electronic properties of bimetallic AgCu and AgAu alloy thin films were studied. • Both AgCu and AgAu bimetallic samples were determined to have cubic crystal geometry. • Strong influence of Cu and Au atoms on the electronic structure of the Ag atoms were determined. - Abstract: Crystal and electronic structure properties of bimetallic AgAu and AgCu alloy thin films were investigated by X-ray spectroscopic techniques. The aim of this study is to probe the influence of Au or Cu atoms on the electronic behaviors of Ag ions in bimetallic alloy materials that yields different crystal properties. To identify the mechanisms causing crystal phase transitions, study were supported by the collected EXAFS (Extended X-ray Absorption Fine Structure) data. Crystal structures of both Cu and Au doped bimetallic Ag samples were determined mainly in cubic geometry with “Fm3m” space group. Through the Ag–Au and Ag–Cu molecular interactions during bimetallic alloy formations, highly overlapped electronic levels that supports large molecular band formations were observed with different ionization states. Besides, traces of the d–d interactions in Au rich samples were determined as the main interplay in the broad molecular bond formations. The exact atomic locations and types in the samples were determined by EXAFS studies and supported by the performed calculations with FEFF scientific code.

  11. Optical properties and structure of Sb-rich AgInSbTe phase change thin films

    Institute of Scientific and Technical Information of China (English)

    张广军; 顾冬红; 干福熹

    2005-01-01

    A new composition content quaternary-alloy-based phase change thin film, Sb-rich AgInSbTe, has been prepared by DC-magnetron sputtering on a K9 glass substrate. After the film has been subsequently annealed at 200 ℃ for 30min,it becomes a crystalline thin film. The diffraction peak of antimony (Sb) are observed by shallow (0.5 degree) x-ray diffraction in the quaternary alloy thin film. The analyses of the measurement from differential scanning calorimetry (DSC) show that the crystallization temperature of the phase change thin film is about 190C and increases with the heating rate. By Kissinger plot, the activation energy for crystallization is determined to be 3.05eV. The refiectivity,refractive index and extinction coefficient of the crystalline and amorphous phase change thin films are presented.The optical absorption coefficient of the phase change thin films as a function of photon energy is obtained from the extinction coefficient. The optical band gaps of the amorphous and crystallization phase change thin films are 0.265eV and 1.127eV, respectively.

  12. Deposition and optical properties of optimised ZnS/Ag/ZnS thin films for energy saving applications

    Energy Technology Data Exchange (ETDEWEB)

    Leftheriotis, G.; Yianoulis, P.; Patrikios, D. [Patras Univ. (Greece). Dept. of Physics

    1997-08-28

    Dielectric/Metal/Dielectric (D/M/D) thin films deposited on glass offer the possibility of significant energy savings in buildings and can find other applications as components of advanced materials design. In an effort to reduce the complexity and cost of production of D/M/D films, physical vapour deposition was used for the laboratory manufacture of ZnS/Ag/ZnS films on glass. ZnS was used because of its high refractive index, ease of deposition and low cost; Ag was used because of its low absorption in the visible spectrum. The films produced were of good quality, with luminous transmittance as high as 83.9%, IR reflectance above 90% and total hemispherical emittance equal to 6%. The ZnS layers were found not only to antireflect the Ag layer, but also to stabilise the ZnS/Ag/ZnS film, improve its adherence on glass and increase the film thermal resistance up to 240 C. A multipurpose computational optics tool based on the characteristic matrix formulation has been developed for the design and optimisation of the D/M/D films: The optimum thickness of each dielectric layer required to maximise the film luminous transmittance for a given metal layer thickness was established. The optical properties of the films designed were also predicted and the most suitable materials were identified. The optical properties of the films produced were measured and were found to compare favourably with the theoretical predictions. (orig.) 29 refs.

  13. Optical and Electrical Properties of Ag-Doped In2S3 Thin Films Prepared by Thermal Evaporation

    Directory of Open Access Journals (Sweden)

    Peijie Lin

    2014-01-01

    Full Text Available Ag-doped In2S3 (In2S3:Ag thin films have been deposited onto glass substrates by a thermal evaporation method. Ag concentration is varied from 0 at.% to 4.78 at.%. The structural, optical, and electrical properties are characterized using X-ray diffraction (XRD, spectrophotometer, and Hall measurement system, respectively. The XRD analysis confirms the existence of In2S3 and AgIn5S8 phases. With the increase of the Ag concentration, the band gap of the films is decreased gradually from 2.82 eV to 2.69 eV and the resistivity drastically is decreased from ~103 to 5.478×10-2 Ω·cm.

  14. Electromigration in Sn–Ag solder thin films under high current density

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, X. [School of Computing and Mathematical Sciences, University of Greenwich, 30 Park Row, London SE10 9LS (United Kingdom); Kotadia, H. [Physics Department, School of Natural and Mathematical Sciences, King' s College London, Strand, London WC2R 2LS (United Kingdom); Xu, S. [Department of Electronic Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kow-loon Tong, Hong Kong (China); Lu, H. [School of Computing and Mathematical Sciences, University of Greenwich, 30 Park Row, London SE10 9LS (United Kingdom); Mannan, S.H. [Physics Department, School of Natural and Mathematical Sciences, King' s College London, Strand, London WC2R 2LS (United Kingdom); Bailey, C. [School of Computing and Mathematical Sciences, University of Greenwich, 30 Park Row, London SE10 9LS (United Kingdom); Chan, Y.C. [Department of Electronic Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kow-loon Tong, Hong Kong (China)

    2014-08-28

    The electro-migration behavior of a Sn–Ag solder thin film stripe that is deposited on a glass substrate has been investigated under a high current density in the absence ofthermo-migration. The distribution of voids and hillocks at current densities of 4.4–6.0 × 10{sup 4} A/cm{sup 2} has been analyzed optically and using electron microscopy. The voids mainly formed at the cathode side of the stripe where maximum current density was predicted but voids also formed along a line that crosses the stripe. This was explained in terms of the initial voids forming at locations of maximum current density concentration, altering these locations, and then expanding into them. The movement of the maximum current density location is caused by redistribution of current as the voids form. An atomic migration model has been developed and used in this work. It was found that if thermal gradients were completely neglected, the model was unable to account for the divergence of atomic flux density which is necessary for void nucleation. However, the temperature dependence of the diffusivity of atoms is sufficient to account for void nucleation within the timescale of the experiments. - Highlights: • Experimental and computational study of electron migration in a SnAg film • The calculated atomic flux divergence has been used to predict void formation. • Voids caused by electromigration observed at current crowding sites and in other regions.

  15. Emission enhancement in indium zinc oxide(IZO)/Ag/IZO sandwiched structure due to surface plasmon resonance of thin Ag film

    Science.gov (United States)

    Kiba, Takayuki; Yanome, Kazuki; Kawamura, Midori; Abe, Yoshio; Kim, Kyung Ho; Takayama, Junichi; Murayama, Akihiro

    2016-12-01

    We report on a photoluminescence (PL) enhancement in IZO/Ag/IZO sandwiched structure via surface plasmonic effects of 14 nm-thick Ag film. In the presence of Ag thin film, the 2-8-fold enhancement was observed for the broad PL around 2.34 eV, which can be originated from defect states in amorphous IZO film. The results of time-resolved PL spectra suggested that the increase in radiative recombination rate, and the maximum Purcell factor of 19 was estimated from the analysis of the PL decay profiles. The comparison between the results of static- and dynamic-PL measurement suggests that the non-radiative process after the excitation of the surface plasmon of the silver film also affects the total efficiency of the emission enhancement.

  16. Texture formation in Ag thin films: Effect of W-Ti diffusion barriers

    Science.gov (United States)

    Bhagat, S. K.; Alford, T. L.

    2008-11-01

    Pure Ag films were deposited on SiO2/Si with and without introduction of W0.7Ti0.3 barrier layers. The films were annealed in vacuum for 1 h at temperatures up to 650 °C. X-ray diffraction pole figure analysis was used to investigate the texture information in as-deposited and annealed films. After annealing, the {111} texture in Ag films increased; however, the degree of increase was significantly higher in Ag/W-Ti/SiO2. In Ag/SiO2 structures, the {200} texture also increased. In Ag/W-Ti/SiO2 structures, no significant increase in {200} texture was observed; however, {111} twin related {511} texture evolved. In as-deposited samples, {111} pole figure revealed that {111} absolute intensity was higher in Ag/SiO2 than in Ag/W-Ti/SiO2. After annealing, Ag {111} intensity was always higher in Ag/W-Ti/SiO2. Sources for the texture evolution were discussed in detail. Field emission scanning electron microscope showed the presence of twins and abnormal grain growth. After annealing at 650 °C, both the roughness and resistivity of Ag increased significantly.

  17. Silver activation on thin films of Ag-ZrCN coatings for antimicrobial activity.

    Science.gov (United States)

    Ferreri, I; Calderon V, S; Escobar Galindo, R; Palacio, C; Henriques, M; Piedade, A P; Carvalho, S

    2015-10-01

    Nowadays, with the increase of elderly population and related health problems, knee and hip joint prosthesis are being widely used worldwide. However, failure of these invasive devices occurs in a high percentage thus demanding the revision of the chirurgical procedure. Within the reasons of failure, microbial infections, either hospital or subsequently-acquired, contribute in high number to the statistics. Staphylococcus epidermidis (S. epidermidis) has emerged as one of the major nosocomial pathogens associated with these infections. Silver has a historic performance in medicine due to its potent antimicrobial activity, with a broad-spectrum on the activity of different types of microorganisms. Consequently, the main goal of this work was to produce Ag-ZrCN coatings with antimicrobial activity, for the surface modification of hip prostheses. Thin films of ZrCN with several silver concentrations were deposited onto stainless steel 316 L, by DC reactive magnetron sputtering, using two targets, Zr and Zr with silver pellets (Zr+Ag target), in an atmosphere containing Ar, C2H2 and N2. The antimicrobial activity of the modified surfaces was tested against S. epidermidis and the influence of an activation step of silver was assessed by testing samples after immersion in a 5% (w/v) NaClO solution for 5 min. The activation procedure revealed to be essential for the antimicrobial activity, as observed by the presence of an inhibition halo on the surface with 11 at.% of Ag. The morphology analysis of the surface before and after the activation procedure revealed differences in silver distribution indicating segregation/diffusion of the metallic element to the film's surface. Thus, the results indicate that the silver activation step is responsible for an antimicrobial effect of the coatings, due to silver oxidation and silver ion release.

  18. Calculation of Elastic Constants of Ag/Pd Superlattice Thin Films by Molecular Dynamics with Many-Body Potentials

    Institute of Scientific and Technical Information of China (English)

    GAO Ning; LAI Wen-Sheng

    2006-01-01

    @@ The calculation of elastic constants of Ag/Pd superlattice thin films by molecular dynamics simulations with many-body potentials is presented. It reveals that the elastic constants C11 and C55 increase with decreasing modulation wavelength A of the films, which is consistent with experiments. However, the change of C11 and C55 with A is found to be around the values determined by a rule of mixture using bulk elastic constants of metals.No supermodulus effect is observed and it is due to cancellation between enhanced and reduced contributions to elastic constants from Ag and Pd layers subjected to compressive and tensile strains, respectively.

  19. Light induced diffusion driven self assembly of Ag nanoparticles in a-Se/Ag bi-layer thin film with ultrafast optical response

    Science.gov (United States)

    Bapna, Mukund; Sharma, Rituraj; Barik, A. R.; Khan, Pritam; Ranjan Kumar, Rakesh; Adarsh, K. V.

    2013-05-01

    In this Letter, we demonstrate that femtosecond light-induced interdiffusion of Ag driven by the electrostatic attraction between photo-excited Ag+ ions and negatively charged amorphous layer can act as an efficient single step method for hybrid integration of spatially ordered and interconnected nanoparticles on the surface of amorphous films. Such self assembled complex hybrid structures of silver nanoparticles via bottom-up nano-construction method on a-Se thin film show an ultrafast optical response over an unusually broad wavelength range that can be used to construct optical modulators operating at switching speed of ˜5 ps.

  20. Fabrication of Ta–Si–N/Ag nanocomposite thin films with near-zero temperature coefficient of resistance

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Haitao; Li, Cuilan [State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Ma, Fei, E-mail: mafei@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Song, Zhongxiao, E-mail: ZhongxiaoSong@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Xu, Kewei, E-mail: kwxu@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi 710049 (China); Department of Physics and Opt-electronic Engineering, Xi’an University of Arts and Science, Xi’an 710065, Shaanxi (China)

    2015-08-15

    Highlights: • Composite thin films with Ag nano-grains uniformly distributed in amorphous Ta–Si–N matrix are obtained. • The temperature coefficient of resistance and the resistivity can be well adjusted by changing Si component. • The balance between quantum tunneling effect and phonon scattering effect results in near-zero TCR. • The near-zero TCR can be maintained at an extremely low temperature from 105 K to 225 K. - Abstract: Ta–Si–N/Ag nanocomposite thin films were prepared by reactive magnetron co-sputtering of Ta, Si and Ag targets in the plasma of N{sub 2} and Ar. It was found that Ag nano-grains were uniformly distributed in the amorphous matrix due to the incorporation of Si. The sizes of Ag grains and the separation between them could be well controlled by changing the Si component, which can be adopted to improve the electronic properties of the composite resistive films. A near-zero temperature coefficient of resistance (TCR) of +39.7 ppm/K was obtained in the thin films with a Si component of 5.88 at.% as a result of the balance of quantum tunneling effect and phonon scattering effect. This is consolidated by the changes in the measured carrier density and Hall mobility at different temperatures. Particularly, the near-zero TCR could be maintained at an extremely low temperature from 105 K to 225 K. The results are of great significance for the exploitation of high-performance resistive thin films.

  1. Ag2ZnSn(S,Se)4: A highly promising absorber for thin film photovoltaics.

    Science.gov (United States)

    Chagarov, Evgueni; Sardashti, Kasra; Kummel, Andrew C; Lee, Yun Seog; Haight, Richard; Gershon, Talia S

    2016-03-14

    The growth in efficiency of earth-abundant kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar cells has slowed, due in part to the intrinsic limitations imposed by the band tailing attributed primarily to I-II antisite exchange. In this study, density functional theory simulations show that when Ag is substituted for Cu to form kesterite Ag2ZnSnSe4 (AZTSe), the I-II isolated antisite formation energy becomes 3.7 times greater than in CZTSSe, resulting in at least an order of magnitude reduction in I-II antisite density. Experimental evidence of an optoelectronically improved material is also provided. Comparison of the low-temperature photoluminescence (PL) structure of Cu(In,Ga)Se2 (CIGSe), CZTSSe, and AZTSe shows that AZTSe has a shallow defect structure with emission significantly closer to the band edge than CZTSe. Existence of suppressed band tailing is found in the proximity of the room-temperature PL peak of AZTSe to its measured band gap. The results are consistent with AZTSe being a promising alternative to CZTSSe and CIGSe for thin film photovoltaics.

  2. Ag2ZnSn(S,Se)4: A highly promising absorber for thin film photovoltaics

    Science.gov (United States)

    Chagarov, Evgueni; Sardashti, Kasra; Kummel, Andrew C.; Lee, Yun Seog; Haight, Richard; Gershon, Talia S.

    2016-03-01

    The growth in efficiency of earth-abundant kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar cells has slowed, due in part to the intrinsic limitations imposed by the band tailing attributed primarily to I-II antisite exchange. In this study, density functional theory simulations show that when Ag is substituted for Cu to form kesterite Ag2ZnSnSe4 (AZTSe), the I-II isolated antisite formation energy becomes 3.7 times greater than in CZTSSe, resulting in at least an order of magnitude reduction in I-II antisite density. Experimental evidence of an optoelectronically improved material is also provided. Comparison of the low-temperature photoluminescence (PL) structure of Cu(In,Ga)Se2 (CIGSe), CZTSSe, and AZTSe shows that AZTSe has a shallow defect structure with emission significantly closer to the band edge than CZTSe. Existence of suppressed band tailing is found in the proximity of the room-temperature PL peak of AZTSe to its measured band gap. The results are consistent with AZTSe being a promising alternative to CZTSSe and CIGSe for thin film photovoltaics.

  3. Antimicrobial properties of Zr–Cu–Al–Ag thin film metallic glass

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hsien-Wei; Hsu, Kai-Chieh; Chan, Yu-Chen [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan (China); Duh, Jenq-Gong, E-mail: jgd@mx.nthu.edu.tw [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan (China); Lee, Jyh-Wei [Department of Materials Engineering, Ming Chi University of Technology, Taipei, Taiwan (China); Center for Thin Film Technologies and Applications, Mingchi University of Technology, Taipei, Taiwan (China); Jang, Jason Shian-Ching [Department of Mechanical Engineering, Institute of Materials Science and Engineering, National Central University, Chung-Li, Taiwan (China); Chen, Guo-Ju [Department of Materials Science and Engineering, I-Shou University, Kaohsiung, Taiwan (China)

    2014-06-30

    Metallic glass as a prominent class of structure and multifunctional materials exhibits several unique properties in mechanical, electrochemical, and thermal properties. This study aimed to realize the advantage of biomedical application and to promote the attainable size of metallic glasses by the physical vapor deposition. The Zr–Cu–Al–Ag thin film metallic glass (TFMG) was deposited on silicon wafer and SUS304 stainless steel substrates by magnetron sputtering with single target. For X-ray diffraction analysis, all TFMGs revealed typical broad peaks around the incident angle of 30 to 50°, suggesting that coatings possess amorphous structure. In addition, diffuse halo ring patterns of transmission electron microscopy indicated a fine amorphorization for TFMG via sputtering process. The variation of surface roughness showed that TFMG derived from higher power of metallic targets revealed rougher morphology. Besides, the roughness of SUS304 stainless steel substrate significantly reduced from 7 nm to about 1 nm after TFMGs were deposited. The microbes of Candida albicans, Escherichia coli, and Pseudomonas aeruginosa were used and cultivated on the TFMG coatings with medium to investigate the antimicrobial properties. In the incubation experiment, the growth of each microbe was recorded by a digital photography system and the growth area was calculated by image processing software. The growth area of the microbes on the TFMG was mostly smaller than that on SUS304 stainless steel ones within incubation time of 72 h, indicating that the TFMGs reveal better antimicrobial capability. Moreover, the coatings exhibit a particularly long-term antimicrobial effect for P. aeruginosa. In summary, the Zr–Cu–Al–Ag prepared by sputtering with a single target device presented superior glass forming ability, and coatings with copper and silver constituents revealed significantly antimicrobial properties. Besides, the surface roughness is another factor to affect the

  4. Growth of ultra-thin FeO(100) films on Ag(100): A combined XPS, LEED and CEMS study

    Science.gov (United States)

    Abreu, G. J. P.; Paniago, R.; Pfannes, H.-D.

    2014-01-01

    The production and characterization of ultra-thin iron oxide films grown on an atomically clean Ag(100) surface by molecular beam epitaxy (MBE) is presented. The goal of this work was to prepare ultra-thin FeO(100) with excellent crystallographic quality. The films were prepared with high purity 57Fe and O2 and afterwards analyzed in situ by means of Low Energy Electron Diffraction (LEED), X-Ray Photoelectron Spectroscopy (XPS) and Conversion Electron Mössbauer Spectroscopy (CEMS). During preparation the evaporation rate, the O2 partial pressure, film thickness and annealing procedures were varied. The analysis of the various samples showed that in general a mixture of FeO and Fe3O4 phases is obtained. We determined the best conditions to produce the desired oxide (FeO). Besides the paramagnetic phase, the antiferromagnetic phase of the FeO films was characterized by low temperature Mössbauer spectra.

  5. Growth of ultra-thin FeO(100) films on Ag(100): A combined XPS, LEED and CEMS study

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, G.J.P., E-mail: guilafis@gmail.com [Department of Physics, Penn State University, University Park, Pennsylvania 16802 (United States); Depto. de Física, ICEx, Universidade Federal de Minas Gerais, CP702 Belo Horizonte - MG (Brazil); Paniago, R.; Pfannes, H.-D. [Depto. de Física, ICEx, Universidade Federal de Minas Gerais, CP702 Belo Horizonte - MG (Brazil)

    2014-01-15

    The production and characterization of ultra-thin iron oxide films grown on an atomically clean Ag(100) surface by molecular beam epitaxy (MBE) is presented. The goal of this work was to prepare ultra-thin FeO(100) with excellent crystallographic quality. The films were prepared with high purity {sup 57}Fe and O{sub 2} and afterwards analyzed in situ by means of Low Energy Electron Diffraction (LEED), X-Ray Photoelectron Spectroscopy (XPS) and Conversion Electron Mössbauer Spectroscopy (CEMS). During preparation the evaporation rate, the O{sub 2} partial pressure, film thickness and annealing procedures were varied. The analysis of the various samples showed that in general a mixture of FeO and Fe{sub 3}O{sub 4} phases is obtained. We determined the best conditions to produce the desired oxide (FeO). Besides the paramagnetic phase, the antiferromagnetic phase of the FeO films was characterized by low temperature Mössbauer spectra. - Highlights: • Highly ordered iron oxide ultra-thin film was grown on Ag(100) single crystal. • The samples were submitted to annealing at various temperatures. • The changes in the iron oxide phases were checked by LEED, XPS and CEMS. • The best conditions to prepare the wüstite and magnetite phases were determined.

  6. AES depth profile and photoconductive studies of AgInS2 thin films prepared by co-evaporation

    Directory of Open Access Journals (Sweden)

    C. A Arredondo

    2014-06-01

    Full Text Available In this study, thin films of AgInS2 with chalcopyrite-type tetragonal structure were grown by means of a procedure based on the sequential evaporation of metallic precursors in presence of elemental sulfur in a two-stage process. The effect of the growth temperature and the proportion of the evaporated Ag mass in relation to the evaporated In mass (mAg/mIn on the phase and homogeneity in the chemical composition were researched through X-ray diffraction measurements and Auger electrons spectroscopy. These measurements evidenced that the conditions for preparing thin films containing only the AgInS2 phase, grown with tetragonal chalcopyrite-type structure and good homogeneity of the chemical composition in the entire volume, are a temperature of 500 °C and a 0.89 mAg/mIn proportion. The transient photocurrent measurements indicated that the electricity transmission is affected by recombination processes via band-to-band transitions and trap-assisted transitions.

  7. A simple synthesis of Ag{sub 2+x}Se nanoparticles and their thin films for electronic device applications

    Energy Technology Data Exchange (ETDEWEB)

    Vo, Duc Quy; Dung, Dang Duc; Cho, Sunglae; Kim, Sunwook [School of Chemical Engineering, University of Ulsan, Ulsan (Korea, Republic of)

    2016-01-15

    A simple method to synthesize silver selenide nanoparticles has been proposed. By changing the ratio of Se-oleylamine complex and silver acetate in the reacting mixture at different temperatures, both size and stoichiometry of the silver selenide particles could be successfully controlled. The size of the nanoparticles was adjusted by changing reaction temperatures. The synthesized silver selenide nanoparticles showed size changes from 3 to 10 nm when the corresponding reaction temperatures were 40-100 .deg. C, respectively. In addition to the size change, the stoichiometry of the synthesized nanoparticles (Ag{sub 2+x}Se) could be adjusted by simply varying the ratio of Ag to Se precursors. Through XPS analyses the x value in Ag{sub 2+x}Se was determined, and it changed between 0.54 and −0.03 by varying Ag/Se ratio from 2/0.75 to 2/4. The optical property of the nonstoichiometric Ag{sub 2+x}Se nanoparticles was different from that of stoichiometric Ag{sub 2}Se nanoparticles, but showed the plasmon absorption of Ag-Ag network. The plasmon absorption was decreased with the increased concentration of the Se precursor. Finally, the Ag{sub 2+x}Se thin film in this work showed large magnetoresistance and successfully applied to prepare high-performance Schottky diode. The Ag{sub 2.06}Se film exhibited the magnetoresistance effect up to 0.9% at only 0.8 T at room temperature. The voltage drop and breakdown voltage of the Schottky diode were 0.5 V and 9.3 V, respectively.

  8. Energy harvesting using ionic electro-active polymer thin films with Ag-based electrodes

    Science.gov (United States)

    Anand, S. V.; Arvind, K.; Bharath, P.; Mahapatra, D. Roy

    2010-04-01

    In this paper we employ the phenomenon of bending deformation induced transport of cations via the polymer chains in the thickness direction of an electro-active polymer (EAP)-metal composite thin film for mechanical energy harvesting. While EAPs have been applied in the past in actuators and artificial muscles, promising applications of such materials in hydrodynamic and vibratory energy harvesting are reported in this paper. For this, functionalization of EAPs with metal electrodes is the key factor in improving the energy harvesting efficiency. Unlike Pt-based electrodes, Ag-based electrodes have been deposited on an EAP membrane made of Nafion. The developed ionic metal polymer composite (IPMC) membrane is subjected to a dynamic bending load, hydrodynamically, and evaluated for the voltage generated against an external electrical load. An increase of a few orders of magnitude has been observed in the harvested energy density and power density in air, deionized water and in electrolyte solutions with varying concentrations of sodium chloride (NaCl) as compared to Pt-based IPMC performances reported in the published literature. This will have potential applications in hydrodynamic and residual environmental energy harvesting to power sensors and actuators based on micro-and nano-electro-mechanical systems (MEMS and NEMS) for biomedical, aerospace and oceanic applications.

  9. CVD elaboration of nanostructured TiO2-Ag thin films with efficient antibacterial properties

    OpenAIRE

    Mungkalasiri, Jitti; Bedel, Laurent; Emieux, Fabrice; Dore, Jeanne; Renaud, François N. R.; Sarantopoulos, Christos; Maury, Francis

    2010-01-01

    Nanostructured TiO2-Ag composite coatings are deposited by direct liquid injection metal-organic (DLI-MO) CVD at 683K in a one-step process. Silver pivalate (AgPiv) and titanium tetra-iso-propoxide (TTIP) are used as Ag and Ti molecular precursors, respectively. Metallic silver nanoparticles are co-deposited with anatase TiO2 on stainless steel, glass, and silicon wafers. The silver particles are uniformly embedded in the oxide matrix through the entire film thickness. The influence of the gr...

  10. Physical properties of Ag-doped cadmium telluride thin films fabricated by closed-space sublimation technique

    Science.gov (United States)

    Abbas Shah, N.; Ali, A.; Aqili, A. K. S.; Maqsood, A.

    2006-05-01

    Cadmium telluride (CdTe) thin films were prepared by the closed-space sublimation (CSS) technique, using CdTe powder as evaporant onto substrates of water-white glass. In the next step, the annealed films at 450 °C for 30 min were dipped in AgNO 3-H 2O solution at room temperature. These films were again annealed at 450 °C for 1 h to obtain silver-doped samples. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), electrically i.e. DC electrical resistivity as well as photo resistivity by van der Pauw method at room temperature, dark conductivity, activation energy analysis as a function of temperature by two-probe method under vacuum, and spectrophotometry. The electron microprobe analyzer (EMPA) results showed an increase of Ag content composition in the samples by increasing the immersion time of films in solution. The Hall measurements indicated the increase in mobility and carrier concentrations of CdTe films by doping of Ag. A significant change in the shape and size of the CdTe grains were observed.

  11. Nanoindentation measurements of the mechanical properties of polycrystalline Au and Ag thin films on silicon substrates: Effects of grain size and film thickness

    Energy Technology Data Exchange (ETDEWEB)

    Cao Yifang [Princeton Institute for the Science and Technology of Materials (PRISM) and Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States)]. E-mail: yifangc@princeton.edu; Allameh, Seyed [Princeton Institute for the Science and Technology of Materials (PRISM) and Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Nankivil, Derek [Department of Mechanical, Materials and Aerospace Engineering, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816 (United States); Sethiaraj, Steve [Department of Physics, University of Botswana, Private Bag UB 0022, Gaborone (Botswana); Otiti, Tom [Department of Physics, Makerere University, Kampala (Uganda); Soboyejo, Wole [Princeton Institute for the Science and Technology of Materials (PRISM) and Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States)

    2006-07-15

    This paper presents the results of nanoindentation experimental studies of the contact-induced deformation in Au and Ag thin films. The paper examines the effects of film thickness and substrate deformation restraint on the mechanical properties of electron beam (e-beam) deposited Au and Ag films. Following a brief description of film microstructure, surface topography, and contact-induced pile-up deformation, film mechanical properties (hardness and Young's modulus) were determined using nanoindentation techniques. The indentation size effects (ISE) observed in films with different thicknesses were explained using a mechanism-based strain gradient (MSG) theory. The intrinsic film yield strengths and hardnesses extracted from the MSG theory are shown to exhibit classical Hall-Petch dependence on the inverse square root of the average film grain size. Displacement bursts were also found to occur in Ag films at indentation load levels of 100 {mu}N. These were attributed to the initial onset of dislocation slip activity, when the shear stress exceeds the estimated theoretical shear strengths of the materials.

  12. Effect of Uniform Decoration of Ag2S Nanoparticles on Physical Properties of Granular TiO2 Thin Films Synthesized by Using Spin Coating Technique

    Directory of Open Access Journals (Sweden)

    R.A. Wagh

    2016-12-01

    Full Text Available In this work, we report the effect of uniform decoration of silver sulphide (Ag2S nanoparticles on physical properties of titanium dioxide (TiO2 nanocrystalline thin films synthesized by using a spin coating technique by preparing TiO2 gel using P-25 TiO2, ethanol, acetyl acetone and p-hydroxybenzoic acid. Chemical bath deposited layer of Ag2S particles enhance the properties of TiO2 nanocrystalline thin films. The optical study reveals that the absorption edge shifts towards the visible region compared with the pure TiO2 thin film due to the incorporation of Ag2S nanoparticles into TiO2 nanocrystalline thin films.

  13. Superconducting YBCO thin film on multicrystalline Ag film evaporated on MgO substrate

    Science.gov (United States)

    Azoulay, Jacob; Verdyan, Armen; Lapsker, Igor

    Superconducting YBa 2Cu 3O 7-δ films were grown by resistive evaporation on multicrystalline silver film which was evaporated on MgO substrate. A simple inexpensive vacuum system equipped with resistively heated boat was used for the whole process. Silver film was first evaporated on MgO substrate kept at 400°C during the evaporation after which with no further annealing a precursor mixture of yttrium small grains and Cu and BaF2 in powder form weighed in the atomic proportion to yield stoichiometric YBa 2Cu 3O 7 was evaporated. The films thus obtained were annealed at 740°C under low oxygen partial pressure of about 1Pa for 30 minutes to form the superconducting phase. X-ray diffraction and scanning electron microscopy techniques were used for texture and surface analysis. Electrical properties were determined using a standard dc four-probe for electrical measurements. The physical and electrical properties of the YBCO films are discussed in light of the fact that X-ray diffraction measurements done on the silver film have revealed a multicrystalline structure

  14. Incommensurate growth of Co thin film on close-packed Ag(111) surface

    Science.gov (United States)

    Barman, Sukanta; Menon, Krishna Kumar S. R.

    2016-05-01

    Growth of ultrathin Co layers on close-packed Ag(111)were investigated by means of Low Energy Electron Diffraction (LEED), X-ray Photoelectron Spectroscopy (XPS) and Angle-resolved Photoemission Spectroscopy(ARPES) techniques. The close-packed hexagonal face of Co(0001), exhibits a lattice misfit about 13% with Ag(111) surface which manipulates the growth to be incommensurate up to a certain thickness. The strain field causes aperiodic height undulation in the sub-angstrom regime of the film which was confirmed by p(1 × 1) LEED pattern along with a 6-fold moiré reconstruction pattern in the lower film thickness (up to ˜2ML). The evolution of the LEED pattern was studied with increasing film coverage. Lattice strain was measured with respect to the relative positions of these double spots as a functionof film thickness. Almost a constant strain (˜13%) in the full range of film thickness explains the moiré pattern formation in order to stabilize the incommensurate growth. For higher film coverages, an epitaxial well-ordered commensurate growth was observed. Core level and valance band electronic structures of these films were studied by XPS and ARPES techniques.

  15. Pure Cubic-Phase Hybrid Iodobismuthates AgBi2 I7 for Thin-Film Photovoltaics.

    Science.gov (United States)

    Kim, Younghoon; Yang, Zhenyu; Jain, Ankit; Voznyy, Oleksandr; Kim, Gi-Hwan; Liu, Min; Quan, Li Na; García de Arquer, F Pelayo; Comin, Riccardo; Fan, James Z; Sargent, Edward H

    2016-08-08

    Bismuth-based hybrid perovskites are candidates for lead-free and air-stable photovoltaics, but poor surface morphologies and a high band-gap energy have previously limited these hybrid perovskites. A new materials processing strategy to produce enhanced bismuth-based thin-film photovoltaic absorbers by incorporation of monovalent silver cations into iodobismuthates is presented. Solution-processed AgBi2 I7 thin films are prepared by spin-coating silver and bismuth precursors dissolved in n-butylamine and annealing under an N2 atmosphere. X-ray diffraction analysis reveals the pure cubic structure (Fd3m) with lattice parameters of a=b=c=12.223 Å. The resultant AgBi2 I7 thin films exhibit dense and pinhole-free surface morphologies with grains ranging in size from 200-800 nm and a low band gap of 1.87 eV suitable for photovoltaic applications. Initial studies produce solar power conversion efficiencies of 1.22 % and excellent stability over at least 10 days under ambient conditions.

  16. Comparative analysis of serial and parallel laser patterning of Ag nanowire thin films

    Science.gov (United States)

    Oh, Harim; Lee, Myeongkyu

    2017-03-01

    Ag nanowire (AgNW) films solution-coated on a glass substrate were laser-patterned in two different ways. For the conventional serial process, a pulsed ultraviolet laser of 30 kHz repetition rate and ∼20 ns pulse width was employed as the laser source. For parallel patterning, the film was directly irradiated by a spatially-modulated Nd:YAG laser beam that has a low repetition rate of 10 kHz and a shorter pulse width of 5 ns. While multiple pulses with energy density ranging from 3 to 9 J/cm2 were required to pattern the film in the serial process, a single pulse with energy density of 0.16 J/cm2 completely removed AgNWs in the parallel patterning. This may be explained by the difference in patterning mechanism. In the parallel process using short pulses of 5 ns width, AgNWs can be removed in their solid state by the laser-induced thermo-elastic force, while they should be evaporated in the serial process utilizing a high-repetition rate laser. Important process parameters such as threshold energy density, speed, and available feature sizes are comparatively discussed for the two patterning

  17. PANI-Ag-Cu Nanocomposite Thin Films Based Impedimetric Microbial Sensor for Detection of E. coli Bacteria

    Directory of Open Access Journals (Sweden)

    Huda Abdullah

    2014-01-01

    Full Text Available PANI-Ag-Cu nanocomposite thin films were prepared by sol-gel method and deposited on the glass substrate using spin coating technique. Polyaniline was synthesized by chemical oxidative polymerization of aniline monomer in the presence of nitric acid. The films were characterized using XRD, FTIR, and UV-Visible spectroscopy. The performance of the sensor was conducted using electrochemical impedance spectroscopy to obtain the change in impedance of the sensor film before and after incubation with E. coli bacteria in water. The peaks in XRD pattern confirm the presence of Ag and Cu nanoparticles in face-centered cubic structure. FTIR analysis shows the stretching of N–H in the polyaniline structure. The absorption band from UV-Visible spectroscopy shows high peaks between 400 nm and 500 nm which indicate the presence of Ag and Cu nanoparticles, respectively. Impedance analysis indicates that the change in impedance of the films decreases with the presence of E. coli. The sensitivity on E. coli increases for the sample with high concentration of Cu.

  18. Nonlinear optical properties of quaternary amorphous Se80.5Bi1.5Te18-yAy (A = Sb, Ag) thin films

    Science.gov (United States)

    Kumar, Anup; Heera, Pawan; Sharma, Raman

    2014-04-01

    Effect of Sb and Ag addition on the optical constants of Se80.5Bi1.5Te18-yAy (A = Sb, Ag and y = 2.0 at. %) thin films, prepared by thermal vacuum evaporation technique, is investigated using Swanepoel method. The optical constants i.e. refractive index (n), film thickness, absorption coefficient and optical energy gap are calculated from the transmission spectra. It has been found that refractive index increases with an increase in Sb or Ag content and the absorption coefficient is also found to increases with increase in optical energy. Whereas the optical band gap decreases with an increase in Sb content and increases with an increase in Ag content. Hence, the present results reveals that the addition of Sb and Ag produce remarkable change on the nonlinear optical properties of the thin film.

  19. Investigation of nanostructured Pd-Ag/n-ZnO thin film based Schottky junction for methane sensing

    Science.gov (United States)

    Roy, S.; Das, S.; Sarkar, C. K.

    2016-07-01

    Undoped nanocrystalline n-type ZnO thin film was deposited by chemical deposition technique on a thermally oxidized p-Si (~5 Ω cm resistivity and orientation) substrate. Formation of stable zinc oxide thin film was confirmed by two-dimensional X-Ray Diffraction (XRD) and EDX analysis. The average crystallite size of the ZnO sample was evaluated as ~50 nm. The surface was characterized by Field Emission Scanning Electron Microscopy (FESEM) and Atomic Force Microscopy (AFM) that confirm the formation of nanocrystalline (grain size ~50 nm) ZnO thin film with surface roughness of ~100 nm. Good conversion of precursor into ZnO thin film in the chemical deposition method was evident by Fourier Transform Infrared Spectroscopy (FTIR). A small peak at 479 cm-1was observed in the FTIR spectrum confirming the formation of quartzite structure of the ZnO. The band gap (~3.44 eV) of the material was calculated from the optical absorption spectroscopy. To prepare Pd-Ag/n-ZnO Schottky junction, Pd-Ag contacts were taken by electron beam evaporation method. I-V characteristics of the junction were studied at different temperatures in inert and reducing ambient (N2 and N2 + CH4) with turn on voltage of around 0.2 V. The parameters like ideality factor ( η), saturation current ( I 0), series resistance ( Rs), and barrier height ( Φ BO) of the junction were calculated in the temperature range 50-200 °C in N2 as well as in 1 % CH4 + N2 ambient. It was observed that the ideality factor decreases in the temperature range 50-200 °C ( η = 12.34 at 50 °C and η = 1.52 at 200 °C) in N2 ambient and η = 1.18 in N2 +CH4 ambient at 200 °C. Schottky Barrier Height ( Φ BO) of the Pd-Ag/n-ZnO junction was found to increase with temperature. A close observation of Pd-Ag/n-ZnO junction in the presence of methane was performed to appreciate its application as methane sensor. The sensing mechanism was illustrated by a simplified energy band diagram.

  20. Ar plasma irradiation improved optical and electrical properties of TiO₂/Ag/TiO₂ multilayer thin film.

    Science.gov (United States)

    Fang, Yingcui; He, Jinjun; Zhang, Kang; Xiao, Chuanyun; Zhang, Bing; Shen, Jie; Niu, Haihong; Yan, Rong; Chen, Junling

    2015-12-01

    Embedding a thin metal layer between two thin dielectric or semiconductor layers [dielectric/metal/dielectric (DMD)] leads to a kind of transparent electrode that is promising as a substitute for the currently widely applied indium tin oxide electrode. However, the optical and electrical properties of DMD still wait for further improvement. In this study, Ar plasma irradiation (API) was, for the first time to our knowledge, applied to improve the optical and electrical properties of a TiO2/Ag/TiO2 electrode that was fabricated by electron-beam evaporation of TiO2 and electric-resistance heating of high purity Ag under vacuum. Ar plasma was produced by radio frequency glow discharge. The Ag layer was bombarded before the second layer of TiO2 was deposited. The electrode with configuration of TiO2 (24  nm)/Ag(14  nm)/TiO2 (24  nm) after API for 10 s shows excellent performance. The mean transmittance between 370 and 800 nm reaches 94% and the sheet resistance is as low as 6  Ω/sq, while Haacke's figure of merit is as high as 112×10(-3)  Ω(-1). The improvement mechanism is discussed based on field emission scanning electron microscope images and absorption spectra. The improvement is attributed to the fact that API reduces the localized surface plasmon resonance of Ag nanoparticles and makes the Ag film thinner and denser.

  1. Synthesis and characterization of photochromic Ag-embedded TiO{sub 2} nanocomposite thin films by non-reactive RF-magnetron sputter deposition

    Energy Technology Data Exchange (ETDEWEB)

    Zuo, J., E-mail: zuojuan@xmut.edu.cn [Department of Materials Science and Engineering, Xiamen University of Technology, Xiamen (China); Department of Interface Chemistry and Surface Engineering, Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany); Keil, P. [Department of Interface Chemistry and Surface Engineering, Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany); Grundmeier, G. [Department of Interface Chemistry and Surface Engineering, Max-Planck-Institut fuer Eisenforschung GmbH, Duesseldorf (Germany); Department of Chemical Engineering and Macromolecular Chemistry, University of Paderborn, Paderborn (Germany)

    2012-07-01

    Ag-embedded TiO{sub 2} nanocomposite thin film with reversible photochromic properties were prepared by layer-by-layer non-reactive RF-magnetron sputtering. Films were produced in Ar/O{sub 2} and pure Ar atmospheres. In the oxidizing regime, a diffusion of Ag from the film volume to the outer film surface was observed. Therefore, pure Ar plasma was applied in the deposition of TiO{sub 2}. The electronic and optical properties of the TiO{sub 2} film were almost not affected by the presence of oxygen. Transmission electron microscopy (TEM) and reflection mode X-ray absorption spectroscopy (XAS) were performed to study the morphology, crystal structure and chemical state of the embedded Ag nanoparticles before and after the annealing step. Annealing of the film led to the crystallization of the TiO{sub 2} matrix. Moreover, the Ag nanoparticles in the film underwent Ostwald ripening leading to particle agglomerate. No oxidation of the embedded Ag during the sputter deposition and subsequent annealing process was found as confirmed by XAS measurements. The non-reactive RF-magnetron method is believed to avoid the energetic oxygen ions attack to Ag during the deposition of Ag-embedded TiO{sub 2} nanocomposite and thus the films are expected to have better optical properties and long-term stability.

  2. Photochromic and self-cleaning properties of TiO2-AgCl/TiO2-xCu thin film.

    Science.gov (United States)

    Sangchay, Weerachai; Sikong, Lek; Kooptarnond, Kalayanee

    2013-02-01

    The TiO2-AgCl/TiO2-xCu thin films were prepared by sol-gel method and dip coated on glass slide. The prepared films were synthesized at the temperature of 400 degrees C for 2 h with a heating rate of 10 degrees C/min. The microstructure and properties of synthesized TiO2-AgCl/TiO2-xCu thin films were characterized by X-ray diffraction, scanning electron microscopy, atomic forced microscope and UV-vis diffuse reflectance spectroscopy. Finally, the hydrophilic property was evaluated by means of contact angle of water droplet on the films. The results show all samples have film thickness in range of 400-500 nm and their surfaces are dense and strong with a large surface area according to the image of atomic forced microscope. It can be noted that TiO2-AgCl/TiO2-5Cu thin films exhibit the highest photochromic (or the lowest capability of light transmittance) at 250-400 nm. The TiO2-AgCl/TiO2-xCu thin films can block UV C, UV B and UV A rays and exhibit self-cleaning effect (small contact angle, 3.9 degrees ) under UV irradiation.

  3. Fabrication of ITO/Ag3SbS3/CdX (X = S, Se) thin film heterojunctions for photo-sensing applications

    Science.gov (United States)

    Daniel, T.; Henry, J.; Mohanraj, K.; Sivakumar, G.

    2016-11-01

    Thin film heterojunctions of Ag3SbS3/CdX (X = S, Se) are deposited on a glass substrate coated with SnO2:In (ITO). The films were characterized by x-ray diffraction (XRD), atomic force microscopy (AFM), UV-visible spectroscopy, photoluminescence spectroscopy, field emission scanning electron microscopy and I-V analysis. XRD reveals the monoclinic structure of Ag3SbS3 and a fcc structure for both CdS and CdSe thin films. The AFM images clearly show the distinct morphological features (nanopyramids, wedge-shaped and rectangular nanorod-like grains). From the I-V studies, under illumination, an ITO/Ag3SbS3/CdS heterojunction produces a higher photocurrent (12.4 mA) than that an ITO/Ag3SbS3/CdSe heterojunction (1.34 mA).

  4. A Solid-State Thin-Film Ag/AgCl Reference Electrode Coated with Graphene Oxide and Its Use in a pH Sensor

    Directory of Open Access Journals (Sweden)

    Tae Yong Kim

    2015-03-01

    Full Text Available In this study, we describe a novel solid-state thin-film Ag/AgCl reference electrode (SSRE that was coated with a protective layer of graphene oxide (GO. This layer was prepared by drop casting a solution of GO on the Ag/AgCl thin film. The potential differences exhibited by the SSRE were less than 2 mV for 26 days. The cyclic voltammograms of the SSRE were almost similar to those of a commercial reference electrode, while the diffusion coefficient of Fe(CN63− as calculated from the cathodic peaks of the SSRE was 6.48 × 10−6 cm2/s. The SSRE was used in conjunction with a laboratory-made working electrode to determine its suitability for practical use. The average pH sensitivity of this combined sensor was 58.5 mV/pH in the acid-to-base direction; the correlation coefficient was greater than 0.99. In addition, an integrated pH sensor that included the SSRE was packaged in a secure digital (SD card and tested. The average sensitivity of the chip was 56.8 mV/pH, with the correlation coefficient being greater than 0.99. In addition, a pH sensing test was also performed by using a laboratory-made potentiometer, which showed a sensitivity of 55.4 mV/pH, with the correlation coefficient being greater than 0.99.

  5. Effect of H{sup +} irradiation on the optical properties of vacuum evaporated AgInSe{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, M.C. Santhosh, E-mail: santhoshmc@nitt.edu [Advanced Materials Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli, Tamil Nadu 620 015 (India); Pradeep, B. [Solid State Physics Laboratory, Department of Physics, Cochin University of Science and Technology, Cochin, Kerala 682 022 (India)

    2009-07-30

    We prepared polycrystalline AgInSe{sub 2} thin films by vacuum evaporation on glass substrate at a high temperature using the stoichiometric powder. The thin films were characterized by X-ray diffraction and UV-vis-NIR spectroscopy. The samples were subjected to the irradiation of 1.26 MeV protons (H{sup +}). The effect of irradiation on the optical properties has been investigated for different doses of H{sup +}. It is observed that the band gap of silver indium selenide thin films decreases gradually with ion irradiation dose.

  6. Structural and optical properties of thin films porous amorphous silicon carbide formed by Ag-assisted photochemical etching

    Energy Technology Data Exchange (ETDEWEB)

    Boukezzata, A., E-mail: assiab2006@yahoo.fr [Silicon Technology Development Unit (UDTS), 02 Bd. Frantz FANON, B.P. 140 Algiers (Algeria); Keffous, A., E-mail: keffousa@yahoo.fr [Silicon Technology Development Unit (UDTS), 02 Bd. Frantz FANON, B.P. 140 Algiers (Algeria); Cheriet, A.; Belkacem, Y.; Gabouze, N.; Manseri, A. [Silicon Technology Development Unit (UDTS), 02 Bd. Frantz FANON, B.P. 140 Algiers (Algeria); Nezzal, G. [Houari Boumediene University (USTHB), Chemical Faculty, Algiers (Algeria); Kechouane, M.; Bright, A. [Houari Boumediene University, Physical Faculty, Algiers (Algeria); Guerbous, L. [Algerian Nuclear Research Center (CRNA), Algiers (Algeria); Menari, H. [Silicon Technology Development Unit (UDTS), 02 Bd. Frantz FANON, B.P. 140 Algiers (Algeria)

    2010-07-01

    In this work, we present the formation of porous layers on hydrogenated amorphous SiC (a-SiC: H) by Ag-assisted photochemical etching using HF/K{sub 2}S{sub 2}O{sub 8} solution under UV illumination at 254 nm wavelength. The amorphous films a-SiC: H were elaborated by d.c. magnetron sputtering using a hot pressed polycrystalline 6H-SiC target. Because of the high resistivity of the SiC layer, around 1.6 M{Omega} cm and in order to facilitate the chemical etching, a thin metallic film of high purity silver (Ag) has been deposited under vacuum onto the thin a-SiC: H layer. The etched surface was characterized by scanning electron microscopy, secondary ion mass spectroscopy, infrared spectroscopy and photoluminescence. The results show that the morphology of etched a-SiC: H surface evolves with etching time. For an etching time of 20 min the surface presents a hemispherical crater, indicating that the porous SiC layer is perforated. Photoluminescence characterization of etched a-SiC: H samples for 20 min shows a high and an intense blue PL, whereas it has been shown that the PL decreases for higher etching time. Finally, a dissolution mechanism of the silicon carbide in 1HF/1K{sub 2}S{sub 2}O{sub 8} solution has been proposed.

  7. Interface controlled growth of nanostructures in discontinuous Ag and Au thin films fabricated by ion beam sputter deposition for plasmonic applications

    Indian Academy of Sciences (India)

    R Brahma; M Ghanashyam Krishna

    2012-08-01

    The growth of discontinuous thin films of Ag and Au by low energy ion beam sputter deposition is reported. The study focuses on the role of the film–substrate in determining the shape and size of nanostructures achieved in such films. Ag films were deposited using Ar ion energy of 150 eV while the Au films were deposited with Ar ion energies of 250–450 eV. Three types of interfaces were investigated in this study. The first set of film–substrate interfaces consisted of Ag and Au films grown on borosilicate glass and carbon coated Cu grids used as substrates. The second set of films was metallic bilayers in which one of the metals (Ag or Au) was grown on a continuous film of the other metal (Au or Ag). The third set of interfaces comprised of discontinuous Ag and Au films deposited on different dielectrics such as SiO2, TiO2 and ZrO2. In each case, a rich variety of nanostructures including self organized arrays of nanoparticles, nanoclusters and nanoneedles have been achieved. The role of the film–substrate interface is discussed within the framework of existing theories of thin film nucleation and growth. Interfacial nanostructuring of thin films is demonstrated to be a viable technique to realize a variety of nanostructures. The use of interfacial nanostructuring for plasmonic applications is demonstrated. It is shown that the surface Plasmon resonance of the metal nanostructures can be tuned over a wide range of wavelengths from 400 to 700 nm by controlling the film–substrate interface.

  8. Determination of the compositions of the DIGM zone in nanocrystalline Ag/Au and Ag/Pd thin films by secondary neutral mass spectrometry

    Directory of Open Access Journals (Sweden)

    Gábor Y. Molnár

    2016-03-01

    Full Text Available Alloying by grain boundary diffusion-induced grain boundary migration is investigated by secondary neutral mass spectrometry depth profiling in Ag/Au and Ag/Pd nanocrystalline thin film systems. It is shown that the compositions in zones left behind the moving boundaries can be determined by this technique if the process takes place at low temperatures where solely the grain boundary transport is the contributing mechanism and the gain size is less than the half of the grain boundary migration distance. The results in Ag/Au system are in good accordance with the predictions given by the step mechanism of grain boundary migration, i.e., the saturation compositions are higher in the slower component (i.e., in Au or Pd. It is shown that the homogenization process stops after reaching the saturation values and further intermixing can take place only if fresh samples with initial compositions, according to the saturation values, are produced and heat treated at the same temperature. The reversal of the film sequence resulted in the reversal of the inequality of the compositions in the alloyed zones, which is in contrast to the above theoretical model, and explained by possible effects of the stress gradients developed by the diffusion processes itself.

  9. Laser direct writing pattern structures on AgInSbTe phase change thin film

    Institute of Scientific and Technical Information of China (English)

    Aihuan Dun; Jingsong Wei; Fuxi Gan

    2011-01-01

    Different pattern structures axe obtained on the AglnSbTe (AIST) phase change film as induced by laser beam. Atomic force microscopy (AFM) was used to observe and analyze the different pattern structures. The AFM photos clearly show the gradually changing process of pattern structures induced by different threshold effects, such as crystallization threshold, microbump threshold, melting threshold, and ablation threshold. The analysis indicates that the AIST material is very effective in the fabrication of pattern structures and can offer relevant guidance for application of the material in the future.%@@ Different pattern structures are obtained on the AgInSbTe(AIST) phase change film as induced by laser beam.Atomic force microscopy(AFM) was used to observe and analyze the different pattern structures.The AFM photos clearly show the gradually changing process of pattern structures induced by different threshold effects,such as crystallization threshold,microbump threshold,melting threshold,and ablation threshold.

  10. Photocatalytic Properties of TiO2 Thin Films Modified with Ag and Pt Nanoparticles Deposited by Gas Flow Sputtering.

    Science.gov (United States)

    Maicu, M; Glöss, D; Frach, Peter; Hecker, D; Gerlach, G; Córdoba, José M

    2015-09-01

    In this work, a gas flow sputtering (GFS) process which allows the production and deposition of metal nanoparticles (NPs) in a vacuum environment is described. Aim of the study is to prove the potential of this technology for the fabrication of new TiO2 films with enhanced photocatalytic properties. For this purpose, Ag and Pt NPs have been produced and deposited on photocatalytic float glass coated with TiO2 thin films by magnetron sputtering. The influence of the process parameters and of the metal amount on the final properties of the particles (quantity, size, size distribution, oxidation state etc.,) was widely investigated. Moreover, the effect of the NPs on the photocatalytic activity of the resulting materials was evaluated for the case of the decomposition of stearic acid (SA) during UV-A irradiation. The reduction of the water contact angle (WCA) during the irradiation period was measured in order to test the photo-induced super-hydrophilicity (PSH).

  11. Effects of Low Ag Doping on Physical and Optical Waveguide Properties of Highly Oriented Sol-Gel ZnO Thin Films

    Directory of Open Access Journals (Sweden)

    Mohamed Dehimi

    2015-01-01

    Full Text Available A sol-gel dip-coating process was used to deposit almost stress-free highly c-axis oriented zinc oxide (ZnO thin films onto glass substrates. The effects of low silver doping concentration (Ag/Zn < 1% on the structural, morphological, optical, and waveguide properties of such films were investigated by X-ray diffraction (XRD, scanning electron microscopy (SEM, atomic force microscopy, UV-Visible spectrophotometry, and M-lines spectroscopy (MLS. XRD analysis revealed that all the films were in single phase and had a hexagonal wurtzite structure. The grain size values were calculated and found to be about 24–29 nm. SEM micrographs and AFM images have shown that film morphology and surface roughness were influenced by Ag doping concentration. According to UV-Vis. measurements all the films were highly transparent with average visible transmission values ranging from 80% to 86%. It was found that the Ag contents lead to widening of the band gap. MLS measurements at 632.8 nm wavelength put into evidence that all thin film planar waveguides demonstrate a well-guided fundamental mode for both transverse electric and transverse magnetic polarized light. Moreover, the refractive index of ZnO thin films was found to increase by Ag doping levels.

  12. Effect of mesh patterning with UV pulsed-laser on optical and electrical properties of ZnO/Ag-Ti thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kao, K.S. [Department of Computer and Communication, SHU-TE University, 59, Hengshan Rd., Yanchao, Kaohsiung County, Taiwan (China); Cheng, D.L., E-mail: dlcheng@stu.edu.tw [Department of Computer and Communication, SHU-TE University, 59, Hengshan Rd., Yanchao, Kaohsiung County, Taiwan (China); Chang, S.H. [Department of Computer and Communication, SHU-TE University, 59, Hengshan Rd., Yanchao, Kaohsiung County, Taiwan (China); Hsieh, P.T. [Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan, Taiwan (China); Chin, H.S. [Opto-Electronics System Section Metal Industries Research and Development Center, Kaohsiung, Taiwan (China); Lin, H.K. [Laser Application Technology Center/Industrial Technology Research Institute South, Liujia Shiang, Taiwan (China)

    2010-10-01

    In this study, the ZnO/Ag-Ti structure for transparence conducting oxide (TCO) is investigated by optimizing the thickness of the Ag-Ti alloy and ZnO layers. The Ag-Ti thin film is deposited by DC magnetron sputtering and its thicknesses is well controlled. The ZnO thin film is prepared by sol-gel method using zinc acetate as cation source, 2-methoxiethanol as solvent and monoethanolamine as solution stabilizer. The ZnO film deposition is performed by spin-coating technique and dried at 150 deg. C on Corning 1737 glass. Due to the conductivity of ZnO/Ag-Ti is dominated by Ag-Ti, the sheet resistance of ZnO/Ag-Ti decrease dramatically as the thickness of Ag-Ti layer increases. However, the transmittances of ZnO/Ag-Ti become unacceptable for TCO application after the thickness of Ag-Ti layer beyond 6 nm. The as-deposited ZnO/Ag-Ti structure has the optical transmittance of 83% - 500 nm and the low resistivity of 1.2 x 10{sup -5} {Omega}-cm. Furthermore, for improving the optical and electrical properties of ZnO/Ag-Ti, the thermal treatment using laser is adopted. Experimental results indicate that the transmittance of ZnO/Ag-Ti is improved from 83% to 89% - 500 nm with resistivity of 1.02 x 10{sup -5} {Omega}-cm after laser drilling. The optical spectrum, the resistance, and the morphology of the ZnO/Ag-Ti will be reported in the study.

  13. Synthesis of Ag-doped hydrogenated carbon thin films by a hybrid PVD–PECVD deposition process

    Indian Academy of Sciences (India)

    Majji Venkatesh; Sukru Taktak; Efstathios I Meletis

    2014-12-01

    Silver-doped hydrogenated amorphous carbon (Ag-DLC) films were deposited on Si substrates using a hybrid plasma vapour deposition–plasma enhanced chemical vapour deposition (PVD–PECVD) process combining Ag target magnetron sputtering and PECVD in an Ar–CH4 plasma. Processing parameters (working pressure, CH4/Ar ratio and magnetron current) were varied to obtain good deposition rate and a wide variety of Ag films. Structure and bonding environment of the films were obtained from transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and Fourier transform infrared (FTIR) spectroscopy studies. Variation of processing parameters was found to produce Ag-doped amorphous carbon or diamond-like carbon (DLC) films with a range of characteristics with CH4/Ar ratio exercising a dominant effect. It was pointed out that Ag concentration and deposition rate of the film increased with the increase in d.c. magnetron current. At higher Ar concentration in plasma, Ag content increased whereas deposition rate of the film decreased. FTIR study showed that the films contained a significant amount of hydrogen and, as a result of an increase in the Ag content in the hydrogenated DLC film, $sp^{2}$ bond content also increased. The TEM cross sectional studies revealed that crystalline Ag particles were formed with a size in the range of 2–4 nm throughout an amorphous DLC matrix.

  14. Effect of Ag underlayer on microstructures and perpendicular magnetic properties of CoPt nanocomposite thin films.

    Science.gov (United States)

    Shen, C L; Kuo, P C; Li, Y S; Lin, G P; Huang, K T; Ou, S L; Chen, S C

    2011-12-01

    CoPt/Ag films were prepared by magnetron sputtering on glass substrates and subsequent annealing. The dependence of degree of ordering and magnetic properties on Ag film thickness and annealing conditions were investigated. It was found that the Ag underlayer played a dominant role in inducing the (001) texture of the CoPt film after annealing. CoPt films with a thickness about 20 nm and Ag underlayers with a thickness about 70 nm are easy to obtain a large degree of ordering and a perpendicular magnetic anisotropy after annealing at 700 degrees C for 30 min. CoPt/Ag films with out-of-plane coercivity (Hc (perpendicular)) in the range of 13.5-14.0 kOe and a out-of-plane squareness (S(perpendicular)) of 0.97 were obtained after annealing at 700 degrees C for 30 min. Ag underlayer is beneficial to enhance the Hc(perpendicular)and S(perpendicular) of CoPt film significantly. The degree of ordering and perpendicular magnetic properties of the CoPt films which deposited on Ag underlayer are larger than those of the single layer CoPt films.

  15. The effect of annealing temperature on electrical and optical properties of transparent and conductive thin films fabicated of multi-walled carbon nanotube/Ag nanowires

    Directory of Open Access Journals (Sweden)

    A zilaee

    2017-02-01

    Full Text Available Transparent and conductive thin films of multi-walled carbon nanotube/ Ag nanowires were fabricated using spin coating technique. In order to improve the electrical conductivity and the optical properties, the layers were annealed from room temperature to 350 °C for 30 minutes. The measurements revealed that annealing caused electrical conductivity of fabricated thin layes to be improved. The optimum annealing temperature for improving these properties was deduced 285 °C. For all different film thicknesses from about 89 to 183 nm it was observed that the presence of nanowires has improved the film’s electrical conductivity in all tempretures. The best ratio of DC conductivity to optical conductivity of the films, which is accounted as films figure of merit, was measured at 285 °C for all Ag percentages. Sheet resistance and optical transmittance were measured by four-point probe technique and UV-Vis spectrophotometer, respectively

  16. X-ray photoelectron spectroscopy studies of Ag-doped thin amorphous Ge{sub x}Sb{sub 40-x}S{sub 60} films

    Energy Technology Data Exchange (ETDEWEB)

    Debnath, R.K.; Fitzgerald, A.G.; Christova, K

    2002-12-30

    X-ray photoelectron spectroscopy has been used to determine the binding energies of the core electrons in Ag-doped amorphous thin Ge{sub x}Sb{sub 40-x}S{sub 60} films (x=15, 20, 25 and 27). Chemical shifts of the constituent elements have revealed that electrons are transferred from chalcogenide to metal and compounds such as Ag{sub 2}S and Ag{sub 2}O are likely to foue to photo-induced chemical modification and oxidation, respectively. Charge defects are induced in the amorphous system.

  17. Growth of NaCl on thin epitaxial KCl films on Ag(100) studied by SPA-LEED

    Science.gov (United States)

    Marquardt, Christian; Paulheim, Alexander; Sokolowski, Moritz

    2015-11-01

    We investigated the growth of NaCl on thin (100)-oriented films of KCl by spot profile analysis of low energy electron diffraction (SPA-LEED). The underlying question of this investigation was how the system accommodates to the misfit of - 10% between the NaCl and KCl lattices. The KCl films (3 atomic layers thick) were epitaxially grown on a Ag(100) single crystal. We studied the heteroepitaxial growth of NaCl on KCl at 300 K and at 500 K, respectively. At 300 K, the first NaCl monolayer (ML) grows pseudomorphically on the KCl film. From the second layer onward, the NaCl lattice relaxes. The NaCl multilayers roughen, and a small rotational disorder (± 4°) of the NaCl domains is observed. The roughening results from the formation of multilayer islands of limited lateral size due to the misfit to the pseudomorphic first NaCl layer. At a growth temperature of 500 K, no pseudomorphic NaCl layer forms, instead relaxed multilayer island growth of NaCl is observed from the first layer onward. Similarly to the growth at 300 K, we find NaCl multilayer islands of limited lateral size. For both temperatures, we explain this growth behavior by the misfit that makes the adsorption sites at the island edges of the first relaxed NaCl layer less favorable for larger islands, promoting nucleation of multilayer islands.

  18. Thin Films

    Directory of Open Access Journals (Sweden)

    M. Benmouss

    2003-01-01

    the optical absorption are consistent with the film color changes. Finally, the optical and electrochromic properties of the films prepared by this method are compared with those of our sputtered films already studied and with other works.

  19. Strain Distribution of Au and Ag Nanoparticles Embedded in Al2O3 Thin Film

    Directory of Open Access Journals (Sweden)

    Honghua Huang

    2014-01-01

    Full Text Available Au and Ag nanoparticles embedded in amorphous Al2O3 matrix are fabricated by the pulsed laser deposition (PLD method and rapid thermal annealing (RTA technique, which are confirmed by the experimental high-resolution transmission electron microscope (HRTEM results, respectively. The strain distribution of Au and Ag nanoparticles embedded in the Al2O3 matrix is investigated by the finite-element (FE calculations. The simulation results clearly indicate that both the Au and Ag nanoparticles incur compressive strain by the Al2O3 matrix. However, the compressive strain existing on the Au nanoparticle is much weaker than that on the Ag nanoparticle. This phenomenon can be attributed to the reason that Young’s modulus of Au is larger than that of Ag. This different strain distribution of Au and Ag nanoparticles in the same host matrix may have a significant influence on the technological potential applications of the Au-Ag alloy nanoparticles.

  20. Characterization of AgGa{sub 0.5}In{sub 0.5}Se{sub 2} thin films deposited by electron-beam technique

    Energy Technology Data Exchange (ETDEWEB)

    Karaagac, H; Parlak, M [Department of Physics, Middle East Technical University, 06531 Ankara (Turkey); Kaleli, M, E-mail: parlak@metu.edu.t [Department of Physics, Sueleyman Demirel University, 32260 Isparta (Turkey)

    2009-08-21

    AgGa{sub 0.5}In{sub 0.5}Se{sub 2} thin films were deposited onto a quartz substrate by the electron-beam technique. For the investigation of the annealing effect on structural, optical and electrical properties of deposited films, samples were annealed in the temperature range 300-775 {sup 0}C. The composition analyses of the deposited films carried out by energy dispersive x-ray analysis measurements have shown that the deposited AgGa{sub 0.5}In{sub 0.5}Se{sub 2} films were indium- and gallium-rich but selenium- and slightly silver-deficient and there was a remarkable change in composition with annealing. As a result of x-ray diffraction measurements, the as-deposited films were found to have an amorphous structure and after annealing at 300 {sup 0}C a polycrystalline structure with different phases was observed. However, subsequent annealing resulted in the formation of single phase AgGa{sub 0.5}In{sub 0.5}Se{sub 2} thin film at about 775 {sup 0}C. The absorption coefficient of the films was determined from the transmission spectra and the band gap values were calculated and found to vary between 1.57 and 2.43 eV following annealing in the temperature range 300-775 {sup 0}C. The refractive index (n) and extinction coefficient (k) of the films were evaluated by applying the envelope method to the transmission spectra. The spectral distributions of these quantities for both as-deposited and annealed films were determined in detail and it was observed that there has been a remarkable influence of annealing on these quantities. The electrical properties of AgGa{sub 0.5}In{sub 0.5}Se{sub 2} thin films were also investigated by means of temperature dependent conductivity measurements in the temperature range 100-460 K. The resistivity of the samples depending on the annealing temperature varied between 6.5 x 10{sup 5} and 16 {Omega} cm. As a result of the hot-probe method it was observed that the as-deposited films have indicated an n-type behaviour, while all the

  1. Two approaches for enhancing the hydrogenation properties of palladium: Metal nanoparticle and thin film over layers

    Indian Academy of Sciences (India)

    Manika Khanuja; B R Mehta; S M Shivaprasad

    2008-11-01

    In the present study, two approaches have been used for enhancing the hydrogenation properties of Pd. In the first approach, metal thin film (Cu, Ag) has been deposited over Pd and hydrogenation properties of bimetal layer Cu (thin film)/Pd(thin film) and Ag(thin film)/Pd(thin film) have been studied. In the second approach, Ag metal nanoparticles have been deposited over Pd and hydrogenation properties of Ag (nanoparticle)/Pd (thin film) have been studied and compared with Ag(thin film)/Pd(thin film) bimetal layer system. The observed hydrogen sensing response is stable and reversible over a number of hydrogen loading and deloading cycles in both bimetallic systems. Alloying between Ag and Pd is suppressed in case of Ag(nanoparticle)/Pd(thin film) bimetallic layer on annealing as compared to Ag (thin film)/Pd(thin film).

  2. Lasting antibacterial activities of Ag-TiO2/Ag/a-TiO2 nanocomposite thin film photocatalysts under solar light irradiation.

    Science.gov (United States)

    Akhavan, O

    2009-08-01

    Photodegradation of Escherichia coli bacteria in presence of Ag-TiO(2)/Ag/a-TiO(2) nanocomposite film with an effective storage of silver nanoparticles was investigated in the visible and the solar light irradiations. The nanocomposite film was synthesized by sol-gel deposition of 30 nm Ag-TiO(2) layer on approximately 200 nm anatase(a-)TiO(2) film previously doped by silver nanoparticles. Both Ag/a-TiO(2) and Ag-TiO(2)/Ag/a-TiO(2) films were transparent with a SPR absorption band at 412 nm. Depth profile X-ray photoelectron spectroscopy showed metallic silver nanoparticles with diameter of 30 nm and fcc crystalline structure were self-accumulated on the film surface at depth of 5 nm of the TiO(2) layer and also at the interface of the Ag-TiO(2) and a-TiO(2) films (at depth of 30 nm). Both OH(-) bounds and H(2)O contents were concentrated on the film surface and at the interface, as a profit in releasing more ionic (not metallic) silver nanoparticles. Antibacterial activity of the nanocomposite film against E. coli bacteria was 5.1 times stronger than activity of the a-TiO(2), in dark. Photo-antibacterial activity of the nanocomposite film exposed by the solar light was measured 1.35 and 6.90 times better than activity of the Ag/a-TiO(2) and a-TiO(2), respectively. The main mechanism for silver ion releasing was inter-diffusion of water and silver nanoparticles through pores of the TiO(2) layer. Durability of the nanocomposite film was at least 11 times higher than the Ag/a-TiO(2) film. Therefore, the Ag-TiO(2)/Ag/a-TiO(2) photocatalyst can be nominated as one of the effective and long-lasting antibacterial nanocomposite materials.

  3. Characterization and antibacterial functions of Ag-TiO2 and W-TiO2 nanostructured thin films prepared by sol-gel/laser-induced technique

    Science.gov (United States)

    Joya, Y. F.; Liu, Z.; Wang, T.

    2011-11-01

    A novel sol-gel/laser-induced technique (SGLIT) has been developed to form nanocrystalline titanium dioxide (TiO2) based thin films with an improved antibacterial performance. TiO2 precursor films loaded with W+6 and Ag+2 ions (W-TiO2, Ag-TiO2) were prepared separately by sol-gel method and spin-coated on microscopic glass slides. As-dried films were subjected to KrF excimer laser pulses at optimized parameters to generate mesoporous anatase and rutile phases at room temperature. The anatase phase was obtained after irradiation with 10 laser pulses only at 75-85 mJ/cm2 fluence in W-TiO2 films. However, higher number of laser pulses and higher W+6 content favored the formation of rutile. Whereas Ag-TiO2 films exhibited anatase up to 200 laser pulses at the same fluence. The films were characterized by using XRD, FEG-SEM, TEM and UV-Vis spectrophotometer to investigate the crystallographic structure, phase transformation, surface morphology, film thickness and the optical properties. A crystallite size of approximately 20 nm was achieved from the anatase prepared by SGLIT. The films exhibited an enhanced antibacterial function against E-Coli cells under the UV excitation.

  4. Ag/Pd纳米复合自组装膜的制备与电催化性质%Preparation of Ag/Pd Nanocomposite Thin Films by Layer-by-Layer Assembly Technique and Their Electrocatalytic Properties

    Institute of Scientific and Technical Information of China (English)

    张莉; 王聪; 王红艳; 张超

    2012-01-01

    利用层层静电自组装技术将聚乙烯亚胺(PEI-Ag+)、PdCl42-交替沉积在基底上,然后用硼氢化钠还原,构筑了含银/钯复合纳米粒子的PEI-Ag/Pd纳米复合薄膜.通过扫描电子显微镜(FESEM),X射线光电子能谱(XPS)和循环伏安(CV)等手段对复合膜的成分、微结构和性质进行了测试分析.膜上生成了不规则和立方体状的银/钯纳米复合物,导致膜表面有一定的粗糙度.结果表明,双金属{PEI-Ag/Pd}n复合膜比单金属{PEI/Pd}n或{PEI-Ag/PSS}n膜对多巴胺的氧化有更好的电催化活性.%Nanocomposite thin films containing Ag/Pd nanoparticles PEI-Ag/Pd were formed by alternating adsorption of PEI-Ag+ and PdCl42- by a layer-by-layer self-assembly technique and subsequent postdeposition reduction by sodium borohydride (NaBH4). The composition, microstructure and properties were characterized by field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV). The Ag/Pd nanocomposites which are irregular and cubic are formed in the films, resulting in a rough surface of the composite film. The results indicate that the {PEI-Ag/Pd}n nanocomposite film exhibits better electrocatalytic activity for the oxidation of dopamine than {PEI/Pd}n and {PEI-Ag/PSS}n films.

  5. Effect of Nanoscale Ag Film Thickness on the Electrical and Optical Properties of Transparent IZTO/Ag/IZTO Multilayer Films Deposited on Glass Substrates.

    Science.gov (United States)

    Oh, Dohyun; Lee, Nam Hyun; Cho, Woon-Jo; Kim, Tae Whan

    2015-07-01

    The effect of nanoscale Ag film thickness on the electrical and optical properties in transparent conducting oxide films consisting of an IZTO/Ag/IZTO multilayer were investigated. The homoge- neous morphologies of the Ag films sandwiched between the IZTO films affected the optical and electrical properties of the IZTO/Ag/IZTO multilayer films. The transmittance and resistivity of the IZTO/Ag/IZTO multilayer films decreased with increasing Ag film thickness. The resistivities of the IZTO/Ag/IZTO multilayer films grown on glass substrates were decreased by using an Ag thin inter- layer in comparison with that of the IZTO single layer.

  6. The structural studies of Ag containing TiO2-SiO2 gels and thin films deposited on steel

    Science.gov (United States)

    Adamczyk, Anna; Rokita, Magdalena

    2016-06-01

    FTIR spectroscopic structural studies of titania-silica monolith samples as well as thin films deposited on steel were described in this work. Thin films were synthesized by the sol-gel method applying the dip coating as separate one-component TiO2 and/or SiO2 layers or as two-component TiO2-SiO2 thin films. Silver nanoparticles were incorporated into the structure from pure SiO2 sol, deposited then as an additional layer in those hybrid multilayers systems. Except the spectroscopic studies, XRD diffraction, SEM microscopy with EDX analysis and AFM microscopy were applied. The structural studies allow to describe and compare the structure and the morphology of thin films, as well those Ag free as Ag containing ones, also by the comparison with the structure of bulk samples. In FTIR spectra, the band observed at about 613 cm-1 can be connected with the presence of the non-tetrahedral cation in the structure and is observed only in the spectra of Ag containing bulk samples and thin films. The bands at 435-467 cm-1 are due to the stretching vibrations of Ti-O bonds or as well to the bending vibrations of O-Si-O one. In the ranges of 779-799 cm-1 and 1027-1098 cm-1, the bands ascribed to the symmetric stretching vibrations and asymmetric vibrations of Si-O-Si connections, respectively, are observed. SEM and AFM images gave the information on the microstructure and the topography of samples surface. XRD measurements confirmed the presence of only amorphous phase in samples up to 500 °C and allowed to observe the tendency of their crystallization.

  7. Influence of a hot and humid environment on thermal transport across the interface between a Ag thin-film line and a substrate

    Science.gov (United States)

    Li, Yuan; Noguchi, Kyohei; Saka, Masumi

    2016-04-01

    To evaluate the reliability of Ag thin-film lines for a wide range of applications in electronic devices, knowledge of the thermal transport across the interface between the line and the underlying substrate is of great importance. This is because such thermal transport significantly affects the temperature distribution in the line, the electrical performance of the line and the service life of the device the line is installed on. In this work, we examine the influence of a hot and humid environment on the thermal transport across the interface between a Ag thin-film line and a substrate. By performing a series of current-stressing experiments using the four-point probe method at atmospheric conditions (296 K and 30 RH%) on a Ag thin-film line for different durations of exposure to a hot and humid environment (323 K and 90 RH%), the electrical resistivity was found to increase with the exposure duration. Such an increase is believed to be the result of a decrease in the interfacial thermal conductance, which indicates less thermal transport from the line to the substrate. Moreover, by observing the surface morphology changes in the line and conducting a one-dimensional electro-thermal analysis, such variations can be attributed to the generation and growth of voids within the line, which hinder heat transfer from the line to the substrate through the interface.

  8. Laser irradiation of ZnO:Al/Ag/ZnO:Al multilayers for electrical isolation in thin film photovoltaics.

    Science.gov (United States)

    Crupi, Isodiana; Boscarino, Stefano; Torrisi, Giacomo; Scapellato, Giorgia; Mirabella, Salvatore; Piccitto, Giovanni; Simone, Francesca; Terrasi, Antonio

    2013-09-23

    Laser irradiation of ZnO:Al/Ag/ZnO:Al transparent contacts is investigated for segmentation purposes. The quality of the irradiated areas has been experimentally evaluated by separation resistance measurements, and the results are complemented with a thermal model used for numerical simulations of the laser process. The presence of the Ag interlayer plays two key effects on the laser scribing process by increasing the maximum temperature reached in the structure and accelerating the cool down process. These evidences can promote the use of ultra-thin ZnO:Al/Ag/ZnO:Al electrode in large-area products, such as for solar modules.

  9. Evenly distributed thin-film Ag coating on stainless plate by tricomponent Ag/silicate/PU with antimicrobial and biocompatible properties.

    Science.gov (United States)

    Huang, Yi-Hsiu; Chen, Mark Hung-Chih; Lee, Bing-Heng; Hsieh, Kuo-Huang; Tu, Yuan-Kun; Lin, Jiang-Jen; Chang, Chih-Hao

    2014-11-26

    A tricomponent nanohybrid dispersion in water comprising silver nanoparticles (AgNP), nanometer-thick silicate platelets (NSP), and water-based polyurethane (PU) was developed for surface coating on orthopedic metal plates. The previously developed AgNP-on-NSP nanohybrid was homogeneously blended into a selected waterborne PU dispersion at varied weight ratios from 1/0.1 to 1/10 (w/w). PU was used to adhere the Ag nanohybrid to the metal surface. The resultant dispersions were analyzed and found to contain AgNP 2-18 nm in diameter and characterized by using UV absorption and TEM micrograph. The subsequent coating of AgNP/NSP-PU dispersion generated a film of 1.5 μm thickness on the metal plate surface, further characterized by an energy dispersive spectroscope (EDS) to show the homogeneous distribution of Ag, Si, and C elements on the metal plates. The surface antimicrobial efficacy was proven for the coating composition of AgNP/NSP to PU ranging from 1/1 to 1/5 by weight ratio but irrelevant to the thickness of the coated materials. The metal plate coated with the high Ag content at 1/1 (w/w) ratio was shown to have very low cytotoxicity toward the contacted mammal fibroblasts. Overall, the optimized tricomponent Ag/silicate/PU in water dispersion from 1/2 to 1/3 (w/w) could generate a stable film on a metal surface exhibiting both antimicrobial and biocompatible properties. The facile coating technique of the AgNP/NSP in waterborne PU is proven to be viable for fabricating infection- and cytotoxicity-free medical devices.

  10. Combinatorial development of antibacterial Zr-Cu-Al-Ag thin film metallic glasses

    Science.gov (United States)

    Liu, Yanhui; Padmanabhan, Jagannath; Cheung, Bettina; Liu, Jingbei; Chen, Zheng; Scanley, B. Ellen; Wesolowski, Donna; Pressley, Mariyah; Broadbridge, Christine C.; Altman, Sidney; Schwarz, Udo D.; Kyriakides, Themis R.; Schroers, Jan

    2016-05-01

    Metallic alloys are normally composed of multiple constituent elements in order to achieve integration of a plurality of properties required in technological applications. However, conventional alloy development paradigm, by sequential trial-and-error approach, requires completely unrelated strategies to optimize compositions out of a vast phase space, making alloy development time consuming and labor intensive. Here, we challenge the conventional paradigm by proposing a combinatorial strategy that enables parallel screening of a multitude of alloys. Utilizing a typical metallic glass forming alloy system Zr-Cu-Al-Ag as an example, we demonstrate how glass formation and antibacterial activity, two unrelated properties, can be simultaneously characterized and the optimal composition can be efficiently identified. We found that in the Zr-Cu-Al-Ag alloy system fully glassy phase can be obtained in a wide compositional range by co-sputtering, and antibacterial activity is strongly dependent on alloy compositions. Our results indicate that antibacterial activity is sensitive to Cu and Ag while essentially remains unchanged within a wide range of Zr and Al. The proposed strategy not only facilitates development of high-performing alloys, but also provides a tool to unveil the composition dependence of properties in a highly parallel fashion, which helps the development of new materials by design.

  11. Characterization of Ag-Cu-S Thin Layers Formed on Low Density Polyethylene Film

    Directory of Open Access Journals (Sweden)

    Ingrida ANCUTIENĖ

    2011-09-01

    Full Text Available The Ag-Cu-S layer formed on PE demonstrated a wide variation in thickness. The cross-section showed the average thickness of sulfide layers on PE increase from 1.9 mm to 5.6 mm with the increase in the sulfurization time and from 1.9 mm to 3.9 mm with the increase of treating time in the solution of copper salts. The electronic micrographs of the sulfide layers indicate the creation of an irregular but continuous base of small dendrites and agglomerates. With the increase in the sulfurization time and treating time in copper (II/I salt solution observed an increase of the agglomerates size. Energy dispersive spectroscopy results indicate that modified layers are poor in copper (0.5 at. % - 1.5 at. %. The atomic ratios of Ag/Cu/S, calculated from the quantification of the peaks (excluded C and O elements give the values (% of 8.3:1.5:4.4, 8.7:0.5:4.3 and 23:1.2:10.9, respectively. In all cases, energy dispersive spectroscopy measurements revealed the modified layers are nearly stoichiometric Ag2S.http://dx.doi.org/10.5755/j01.ms.17.3.584

  12. Effects of Ag layers on the SiO2/FePt thin films deposited by magnetron sputtering

    Institute of Scientific and Technical Information of China (English)

    FAN Jiuping; XU Xiaohong; WANG Fang; JIANG Fengxian; TIAN Baoqiang; JIN Tao

    2008-01-01

    The effects of Ag Iayers with different locations and thicknesses on the structural and magnetic property of SiO2/FePt multilayer films were investigated.The non-magnetic Ag layer plays an important role in inducing(001)orientation and ordering of FePt grains,as well as the SiO2-doping reducing the grin size and the magnetic exchange coupling between grains.When the 10 nm Ag layer is moved from the bottom to the top of the SiO2/FePt multilayer film,the coercivity gradually decreases;the largest difference betwogn the out-of-plane coercivity and the in-plane one is obtained in the sample of[SiO2(2 nm)/FePt(3 nm)]3/Ag(10 nm)/[SiO2(2 nm)//FePt(3 nm)]2.Furthermore,the location of Ag layers was fixed and the thickness was changed.The XRD curves suggest that the intensity of the(001)peak becomes the strongest with the addition of 10 nm Ag layers.

  13. Thermally deposited Ag-doped CdS thin film transistors with high-k rare-earth oxide Nd{sub 2}O{sub 3} as gate dielectric

    Energy Technology Data Exchange (ETDEWEB)

    Gogoi, P., E-mail: paragjyoti_g@rediffmail.com [Sibsagar College, Material Science Laboratory, Department of Physics (India)

    2013-03-15

    The performance of thermally deposited CdS thin film transistors doped with Ag has been reported. Ag-doped CdS thin films have been prepared using chemical method. High dielectric constant rare earth oxide Nd{sub 2}O{sub 3} has been used as gate insulator. The thin film trasistors are fabricated in coplanar electrode structure on ultrasonically cleaned glass substrates with a channel length of 50 {mu}m. The thin film transistors exhibit a high mobility of 4.3 cm{sup 2} V{sup -1} s{sup -1} and low threshold voltage of 1 V. The ON-OFF ratio of the thin film transistors is found as 10{sup 5}. The TFTs also exhibit good transconductance and gain band-width product of 1.15 Multiplication-Sign 10{sup -3} mho and 71 kHz respectively.

  14. Growth of Ag thin films on ZnO(0 0 0 -1) investigated by AES and STM

    Energy Technology Data Exchange (ETDEWEB)

    Duriau, E. [Interuniversity Microelectronic Center (IMEC), SPDT-MCA, Kapeldreef 75, B-3001 Leuven (Belgium); Agouram, S. [Dpto. Fisica Aplicada y Electromagnetismo c/Dr. Moliner no. 50, 46100 Burjassot, Valencia (Spain); Laboratoire de Physique des Materiaux Electroniques (LPME), University of Namur, Rue de Bruxelles 61, B-5000 Namur (Belgium); Morhain, C. [Centre de Recherche sur l' HeteroEpitaxie et ses Applications (CRHEA), CNRS, Rue Bernard Gregory, F-06560 Valbonne Sophia-Antipolis (France); Seldrum, T. [Laboratoire de Physique des Materiaux Electroniques (LPME), University of Namur, Rue de Bruxelles 61, B-5000 Namur (Belgium); Sporken, R. [Laboratoire de Physique des Materiaux Electroniques (LPME), University of Namur, Rue de Bruxelles 61, B-5000 Namur (Belgium); Dumont, J. [Laboratoire de Physique des Materiaux Electroniques (LPME), University of Namur, Rue de Bruxelles 61, B-5000 Namur (Belgium)]. E-mail: jacques.dumont@fundp.ac.be

    2006-11-15

    The growth of Ag films on ZnO(0 0 0 -1) has been investigated by Auger electron spectroscopy (AES) and scanning tunneling microscopy (STM). A high density of islands is nucleated at the earliest stages of the growth. An upstepping mechanism causes these islands to coalesce while the uncovered fraction of the ZnO surface remains constant (30%)

  15. 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

  16. 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.

  17. Ohmic contacts of Au and Ag metals to n-type GdN thin films

    Directory of Open Access Journals (Sweden)

    Felicia Ullstad

    2015-05-01

    Full Text Available The rare-earth nitrides appear as attractive alternatives to dilute ferromagnetic semiconductors for spintronics device applications. Most of them combine the properties of the ferromagnet and the semiconductor, an exceedingly rare combination. In this work we have grown n-type polycrystalline semiconducting GdN layers between pre-deposited contacts made of Cr/Au and Cr/Ag. The resistivity of the GdN layers ranges from 4.4×10-4 Ωcm to 3.1×10-2 Ωcm depending on the nitrogen pressure during the growth. The electrical properties of metal/n-type GdN/metal planar junctions are investigated as a function of the temperature. The current voltage characteristics of the junctions were linear for temperatures ranging from 300 K down to 5 K, suggesting an ohmic contact between the Au or Ag metal and the n-type GdN layer.

  18. Enhanced Thermochromic Properties and Solar-Heat Shielding Ability of W(x)V(1-x)O2 Thin Films with Ag Nanowires Capping Layers.

    Science.gov (United States)

    Zhao, Li Li; Miao, Lei; Liu, Cheng Yan; Wang, Hai Long; Tanemura, Sakae; Sun, Li Xian; Gao, Xiang; Zhou, Jian Hua

    2015-11-01

    Considerable efforts have been made to shift the phase transition temperature of metal-doped vanadium dioxide (VO2) films nearer the ambient temperature while maintain the excellent thermochromic properties simultaneously. Here, we describe a facile and economic solution-based method to fabricate W-doped VO2 (V(1-x)W(x)O2) thin films with excellent thermochromic properties for the application of smart windows. The substitutional doping of tungsten atoms notably reduces the phase transition temperature to the ambient temperature and retains the excellent thermochromic property. Furthermore, Ag nanowires (NWs) are employed as capping layers to effectively decrease the thermal emissivity from 0.833 to 0.603, while the original near infrared region (NIR) modulation ability is not severely affected. Besides, the Ag NWs layers further depress the phase transition temperature as well as the hysteresis loop width, which is important to the fenestration application. These solution-grown Ag NWs/V(1-x)W(x)O2 thin films exhibit excellent solar modulation ability, narrowed hysteresis loop width as well as low thermal emissivity, which provide a promising perspective into the practical application of VO2-based smart windows.

  19. Optical and electrical properties and phonon drag effect in low temperature TEP measurements of AgSbSe2 thin films

    Science.gov (United States)

    Namitha Asokan, T.; Urmila, K. S.; Jacob, Rajani; Reena Philip, Rachel; Okram, G. S.; Ganesan, V.; Pradeep, B.

    2014-05-01

    Polycrystalline thin films of silver antimony selenide have been deposited using a reactive evaporation technique onto an ultrasonically cleaned glass substrate at a vacuum of 10-5 torr. The preparative parameters, like substrate temperature and incident fluxes, have been properly controlled in order to get stoichiometric, good quality and reproducible thin film samples. The samples are characterized by XRD, SEM, AFM and a UV—vis—NIR spectrophotometer. The prepared sample is found to be polycrystalline in nature. From the XRD pattern, the average particle size and lattice constant are calculated. The dislocation density, strain and number of crystallites per unit area are evaluated using the average particle size. The dependence of the electrical conductivity on the temperature has also been studied and the prepared AgSbSe2 samples are semiconducting in nature. The AgSbSe2 thin films exhibited an indirect allowed optical transition with a band gap of 0.64 eV. The compound exhibits promising thermoelectric properties, a large Seebeck coefficient of 30 mV/K at 48 K due to strong phonon electron interaction. It shows a strong temperature dependence on thermoelectric properties, including the inversion of a dominant carrier type from p to n over a low temperature range 9-300 K, which is explained on the basis of a phonon drag effect.

  20. Thin-film metallic glass: an effective diffusion barrier for Se-doped AgSbTe2 thermoelectric modules

    Science.gov (United States)

    Yu, Chia-Chi; Wu, Hsin-jay; Deng, Ping-Yuan; Agne, Matthias T.; Snyder, G. Jeffrey; Chu, Jinn P.

    2017-01-01

    The thermal stability of joints in thermoelectric (TE) modules, which are degraded during interdiffusion between the TE material and the contacting metal, needs to be addressed in order to utilize TE technology for competitive, sustainable energy applications. Herein, we deposit a 200 nm-thick Zr-based thin-film metallic glass (TFMG), which acts as an effective diffusion barrier layer with low electrical contact resistivity, on a high-zT Se-doped AgSbTe2 substrate. The reaction couples structured with TFMG/TE are annealed at 673 K for 8–360 hours and analyzed by electron microscopy. No observable IMCs (intermetallic compounds) are formed at the TFMG/TE interface, suggesting the effective inhibition of atomic diffusion that may be attributed to the grain-boundary-free structure of TFMG. The minor amount of Se acts as a tracer species, and a homogeneous Se-rich region is found nearing the TFMG/TE interface, which guarantees satisfactory bonding at the joint. The diffusion of Se, which has the smallest atomic volume of all the elements from the TE substrate, is found to follow Fick’s second law. The calculated diffusivity (D) of Se in TFMG falls in the range of D~10−20–10−23(m2/s), which is 106~107 and 1012~1013 times smaller than those of Ni [10−14–10−17(m2/s)] and Cu [10−8–10−11(m2/s)] in Bi2Te3, respectively.

  1. Synthesis and characterization of silver diethyldithiocarbamate cluster for the deposition of acanthite (Ag{sub 2}S) thin films for photoelectrochemical applications

    Energy Technology Data Exchange (ETDEWEB)

    Ehsan, Muhammad Ali; Khaledi, Hamid [Department of Chemistry, Faculty of Science, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia); Tahir, Asif Ali [Department of Chemistry, Loughborough University, Loughborough LE 11 3TU (United Kingdom); Ming, Huang Nay [Department of Physics, Faculty of Science, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia); Wijayantha, K.G. Upul [Department of Chemistry, Loughborough University, Loughborough LE 11 3TU (United Kingdom); Mazhar, Muhammad, E-mail: mazhar42pk@yahoo.com [Department of Chemistry, Faculty of Science, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)

    2013-06-01

    Acanthite (Ag{sub 2}S) thin films were fabricated on fluorine doped tin oxide coated conducting glass substrates by aerosol assisted chemical vapor deposition (AACVD) using silver cluster [Ag{sub 4}{S_2CN(C_2H_5)_2}{sub 3}(C{sub 5}H{sub 5}N){sub 2}]{sub n}·nNO{sub 3}·2nH{sub 2}O (1) [where (S{sub 2}CN(C{sub 2}H{sub 5}){sub 2}) = diethyldithiocarbamate, C{sub 5}H{sub 5}N = pyridine] as a single source precursor. Cluster (1) was synthesized by the reaction of sodium diethyldithiocarbamate with silver nitrate in a mixture of acetone and pyridine. (1) was analyzed by melting point, elemental analysis, Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, thermogravimetry and single crystal X-ray studies. Single crystal X-ray studies showed that (1) crystallizes in the triclinic crystal system with a = 11.4372(3), b = 11.6768(3), and c = 16.3672(4) Å and α = 105.817(3), β = 97.891(3), and γ = 93.274(3)° in the space group P-1. Thermogravimetric analysis revealed that (1) undergoes facile thermal decomposition at 400 °C to give a stable residual mass consistent with the formation of Ag{sub 2}S. Thin films grown from a 0.02 M solution of (1) in pyridine at 350 and 400 °C using AACVD technique were characterized by powder X-ray diffraction, field emission scanning electron microscopy (FESEM), energy dispersive X-ray and ultraviolet-visible spectrophotometry. FESEM images of the films exhibited well-defined nanorods with length > 1000 nm and diameter 100–150 nm grown without any cracks, fractures or directional preference. A band gap of 1.05 eV was estimated by extrapolating the linear part of a Tauc plot recorded for the films. The photoelectrochemical (PEC) characteristics recorded under Air Mass 1.5 illumination indicated a photocurrent density of 220 μA cm{sup −2} at 0.0 V vs Ag/AgCl/3 M KCl. The optical and PEC characteristics of the deposited thin films proved their suitability for PEC applications. - Highlights:

  2. Enhancement in the excitonic spontaneous emission rates for Si nanocrystal multi-layers covered with thin films of Au, Ag, and Al.

    Science.gov (United States)

    Estrin, Y; Rich, D H; Rozenfeld, N; Arad-Vosk, N; Ron, A; Sa'ar, A

    2015-10-30

    The enhancement in the spontaneous emission rate (SER) for Ag, Au, and Al films on multilayer Si nanocrystals (SiNCs) was probed with time-resolved cathodoluminescence (CL). The SiNCs were grown on Si(100) using plasma enhanced chemical vapor deposition. Electron-hole pairs were generated in the metal-covered SiNCs by injecting a pulsed high-energy electron beam through the thin metal films, which is found to be an ideal method of excitation for plasmonic quantum heterostructures and nanostructures that are opaque to laser or light excitation. Spatially, spectrally, and temporally resolved CL was used to measure the excitonic lifetime of the SiNCs in metal-covered and bare regions of the same samples. The observed enhancement in the SER for the metal-covered SiNCs, relative to the SER for the bare sample, is attributed to a coupling of the SiNC excitons with surface plasmon polaritons (SPPs) of the thin metal films. A maximum SER enhancement of ∼2.0, 1.4 and 1.2 was observed for the Ag, Au, and Al films, respectively, at a temperature of 55 K. The three chosen plasmonic metals of Ag, Au, and Al facilitate an interesting comparison of the exciton-SPP coupling for metal films that exhibit varying differences between the surface plasmon energy, ω(sp), and the SiNC excitonic emission energy. A modeling of the temperature dependence of the Purcell enhancement factor, Fp, was performed and included the temperature dependence of the dielectric properties of the metals.

  3. Synthesis of ZnO Nanowires and Their Photovoltaic Application: ZnO Nanowires/AgGaSe2 Thin Film Core-Shell Solar Cell

    Directory of Open Access Journals (Sweden)

    Elif Peksu

    2015-01-01

    Full Text Available In this investigation, hydrothermal technique was employed for the synthesis of well-aligned dense arrays of ZnO nanowires (NWs on a wide range of substrates including silicon, soda-lime glass (SLG, indium tin oxide, and polyethylene terephthalate (PET. Results showed that ZnO NWs can be successfully grown on any substrate that can withstand the growth temperature (~90°C and precursor solution chemicals. Results also revealed that there was a strong impact of growth time and ZnO seed layer deposition route on the orientation, density, diameter, and uniformity of the synthesized nanowires. A core-shell n-ZnO NWs/p-AgGaSe2 (AGS thin film solar cell was fabricated as a device application of synthesized ZnO nanowires by decoration of nanowires with ~700 nm thick sputtering deposited AGS thin film layer, which demonstrated an energy conversion efficiency of 1.74% under 100 mW/cm2 of simulated solar illumination.

  4. Optical and thermal investigation of GeO{sub 2}-PbO thin films doped with Au and Ag nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, E.A.; Carmo, A.P. [Laboratorio de Espectroscopia de Materiais, Departamento de Fisica, Universidade Federal de Juiz de Fora, Juiz de Fora-MG (Brazil); Bell, M.J.V., E-mail: mjbell@fisica.ufjf.br [Laboratorio de Espectroscopia de Materiais, Departamento de Fisica, Universidade Federal de Juiz de Fora, Juiz de Fora-MG (Brazil); Anjos, V. [Laboratorio de Espectroscopia de Materiais, Departamento de Fisica, Universidade Federal de Juiz de Fora, Juiz de Fora-MG (Brazil); Kassab, L.R.P. [Laboratorio de Tecnologia em Materiais Fotonicos e Optoeletronicos, Faculdade de Tecnologia de Sao Paulo, Sao Paulo (Brazil); Silva, D.M. da [Departamento de Engenharia de Sistemas Eletronicos, Escola Politecnica da USP, Sao Paulo, Sao Paulo (Brazil)

    2012-01-31

    The present work reports on the thermo-optical study of germanate thin films doped with Au and Ag nanoparticles. Transmission Electron Microscopy images, UV-visible absorption and Micro-Raman scattering evidenced the presence of nanoparticles and the formation of collective excitations, the so called surface plasmons. Moreover, the effects of the metallic nanoparticles in the thermal properties of the films were observed. The thermal lens technique was proposed to evaluate the Thermal Diffusivity (D) of the samples. It furnishes superficial spatial resolution of about 100 {mu}m, so it is appropriate to study inhomogeneous samples. It is shown that D may change up to a factor 3 over the surface of a film because of the differences in the nanoparticles concentration distribution.

  5. Photocatalytic degradation of methylene blue using undoped and Ag-doped TiO{sub 2} thin films deposited by a sol-gel process: Effect of the ageing time of the starting solution and the film thickness

    Energy Technology Data Exchange (ETDEWEB)

    Guillen-Santiago, A.; Mayen, S.A.; Torres-Delgado, G.; Castanedo-Perez, R. [Laboratorio de Investigacion en Materiales, CINVESTAV-IPN, U. Queretaro, Apdo. Postal 1-798, Queretaro, Qro. 76001 (Mexico); Maldonado, A. [Departamento de Ingenieria. Electrica-SEES, CINVESTAV-IPN, Apdo. Postal 14-740, Mexico D.F. 07000 (Mexico); Olvera, M. de la L, E-mail: molvera@cinvestav.mx [Departamento de Ingenieria, Electrica-SEES, CINVESTAV-IPN, Apdo. Postal 14-740, Mexico D.F. 07000 (Mexico)

    2010-10-25

    Undoped and Ag-doped TiO{sub 2} thin films were deposited on glass substrates by the sol-gel method. A novel propose to prepare the solution is the use of titanium monohydrate oxyacetyl acetonate as the starting reagent. The effect of the ageing time of the starting solution as well as the number of coatings on the photocatalytic degradation of methylene blue (MB) was studied. The variation of the absorption spectra shows the degradation of MB dissolved in water, as a result of the reaction produced on the surface of the films, and promoted by ultraviolet irradiation during 5 h. The results show an optimum photocatalytic activity, in the order of 35%, presented in the 5-immersion Ag-doped TiO{sub 2} thin films, deposited from 7- and 14-day aged solutions. On the other hand, the Ag-doped TiO{sub 2} films deposited at different coatings show small changes in the photocatalytic activity. Morphological studies show the presence of silver particles on the film surface, due to the different number of coatings, affecting the photocatalytic performance.

  6. 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.

  7. Study of NBE emission enhancement with an absence of DL emission from ZnO nanorods through controlled growth on ultra-thin Ag films

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Anil Kumar; Bharathi Mohan, D., E-mail: d.bharathimohan@gmail.com

    2015-04-01

    Highlights: • The growth of ZnO nanorods (NRs) is controlled on ultra-thin Ag layer after modifying its surface properties including particle size, number particles density, inter-particles distance and crystallinity. • Ag layer is not only acting as a catalyst for the vertical growth of ZnO NRs and also the corresponding plasmon resonance frequency is tuned and coupled with the excitonic frequency of ZnO NRs. • This type of hybrid structure leads to strong NBE emission enhancement without a broad deep level emission. The absence of DL emission suggests that there is no oxygen vacancy which is found to be very unusual in ZnO nanorods. • The possible reason for the NBE emission enhancement is explained through annealing of ultra thin Ag inter-layer, surface roughness and density of ZnO nanorods. The NBE emission enhancement on ZnO/Ag has been studied through charge transfers by giving a suitable band diagram. - Abstract: ZnO nanorods (NRs) exhibiting enhanced ultra-violet near band edge (UV-NBE) emission without a broad visible deep level (DL) emission has been investigated on catalytically grown ZnO/Ag hybrid nanostructure. The hybrid structure is fabricated in two steps, (1) Thermal evaporation of ultra-thin catalytic layer of Ag with mass thickness ∼1 nm on glass substrate followed by annealing process from 50 to 250 °C and (2) vertical growth of ZnO NRs by hydrothermal reaction process on all Ag films. The surface properties of Ag layer such as particle size, inter-particle distance, particles number density, surface roughness and surface coverage area were altered through annealing process. Annealing at 100 °C modifies Ag from quasi-amorphous to nanocrystalline leading to high density growth and high aspect ratio of ZnO NRs where as a random and less density growth was realized at 250 °C due to increase of both particle size and inter-particles distance in Ag layer. X-ray diffraction reveals a predominant growth of (0 0 2) plane at 100

  8. Ion-modulated nonlinear electronic transport in carbon nanotube bundle/RbAg4I5 thin film composite nanostructures

    Science.gov (United States)

    Sun, Jia-Lin; Zhang, Wei; Wei, Jinquan; Gu, Bingfu

    2014-01-01

    We have explored the ion-modulated electronic transport properties of mixed ionic-electronic conductor (MIEC) composite nanostructures made of superionic conductor RbAg4I5 films and carbon nanotube (CNT) bundle spiderwebs. Our experimental and theoretical studies indicate that the formation of ion-electron bound states (IEBSs) leads to strong ion-electron interference effect and interesting electronic transport of CNT, such as nonlinear current-voltage (I-V) characteristics and novel temperature dependence of the current. With increasing temperature, the hybrid nanostructures show rich phases with different dependence of current on temperature, which is related to the structural phase transition of RbAg4I5 and the transition of dissociation of IEBSs. The ion-modulation of the electric conductivity in such MIEC composite nanostructures with great tunability has been used to design new ionic-electronic composite nano-devices with function like field effect transistor.

  9. 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...

  10. Tuning the opto-electrical properties of SnO{sub 2} thin films by Ag{sup +1} and In{sup +3} co-doping

    Energy Technology Data Exchange (ETDEWEB)

    Mouchaal, Younes [Laboratoire de Physique des Couches Minces et Matériaux pour l’Electronique (LPCMME) Université de Oran, BP 1524 EL M-Naouer 31000, Oran (Algeria); Enesca, Alexandru, E-mail: aenesca@unitbv.ro [Center for Renewable Energy Systems and Recycling, R& D Institute of the Transilvania University of Brasov, Eroilor 29 Street, 500036, Brasov (Romania); Mihoreanu, Ciprian [Center for Renewable Energy Systems and Recycling, R& D Institute of the Transilvania University of Brasov, Eroilor 29 Street, 500036, Brasov (Romania); Khelil, Abdelbacet [Laboratoire de Physique des Couches Minces et Matériaux pour l’Electronique (LPCMME) Université de Oran, BP 1524 EL M-Naouer 31000, Oran (Algeria); Duta, Anca [Center for Renewable Energy Systems and Recycling, R& D Institute of the Transilvania University of Brasov, Eroilor 29 Street, 500036, Brasov (Romania)

    2015-09-15

    Graphical abstract: - Highlights: • Polycrystalline SnO{sub 2} tetragonal structure with preferential (1 1 0) orientation. • Silver segregation and oxidation threshold. • Suitable diode-type behavior observed for the samples rich in silver. • Higher silver doping (8–12 at%) increases the grains’ size. - Abstract: In this work transparent thin films of Ag{sup +1}-In{sup +3} co-doped SnO{sub 2} were obtained using robotic spray pyrolysis. The effect of silver doping concentration on their optical, electrical and structural properties was investigated. Silver co-doping was varied between 0 and 12 at% in the precursor solution keeping the concentration of indium fixed at 2 at%. The optical transmittance has values between 90.3 and 82.7%, when the Ag{sup +1} doping ranges from 0 to 12 at%. The X-ray diffraction shows a single SnO{sub 2} phase, for silver doping between 0 and 8 at%, and a new silver oxide phase when the silver increases up to 12 at%. The current–voltage characteristics show diode-like behavior for low and high doping concentrations, corresponding to 2 and 12 at%. The films exhibit photocurrent which is affected by the silver amount in the structure. The highest and most stable generated photocurrent was achieved for samples with 12 at% Ag{sup +1}.

  11. Modifications induced in the structural and optical properties of bismuth sodium borosilicate glass thin films by 120 MeV Ag{sup 7+} ions

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Ravneet, E-mail: ravneet_383@yahoo.com [Department of Physics, Guru Nanak Dev University, Amritsar 143 005 (India); Singh, Surinder [Department of Physics, Guru Nanak Dev University, Amritsar 143 005 (India); Pandey, O.P. [School of Physics and Materials Science, Thapar University, Patiala 147 004 (India)

    2013-06-15

    The composition of the glass is Bi{sub 2}O{sub 3} (20%)–Na{sub 2}O (15%)–B{sub 2}O{sub 3} (50%)–SiO{sub 2} (15%) was prepared by conventional melt quench method. To study the effect of heavy ion irradiation on the glass network and structural units, thin films of the glass have been prepared by electron beam gun evaporation. The prepared films are irradiated using 120 MeV Ag{sup 7+} ions in the fluence range of 1 × 10{sup 12}–3 × 10{sup 13} ions cm{sup −2}. The optical and structural properties were investigated using UV–visible absorption spectroscopy and Fourier Transform Infrared (FTIR) spectroscopic techniques. A significant decrease in the band gap is observed after irradiation which is indicative of the fact that radiation has caused compaction in the glass structure.

  12. Effect of 100 MeV Ag+7 ion irradiation on the bulk and surface magnetic properties of Co-Fe-Si thin films

    Science.gov (United States)

    Hysen, T.; Geetha, P.; Al-Harthi, Salim; Al-Omari, I. A.; Lisha, R.; Ramanujan, R. V.; Sakthikumar, D.; Avasthi, D. K.; Anantharaman, M. R.

    2014-12-01

    Thin films of Co-Fe-Si were vacuum evaporated on pre-cleaned float glass substrates employing thermal evaporation. The films were subsequently irradiated with 100 MeV Ag+7 ions at fluences of 1×1011, 1×1012 and 1×1013 ions/cm2. The pristine and irradiated samples were subjected to surface analysis using Atomic Force Microscopy (AFM), Vibrating Sample Magnetometry (VSM) and Magneto Optic Kerr Effect (MOKE) measurements. The as deposited film has a root mean square roughness (Rq) of 8.9 nm and an average roughness of (Ra) 5.6 nm. Irradiation of the as deposited films with 100 MeV Ag7+ ions modifies the surface morphology. Irradiating with ions at fluences of 1×1011 ions/cm2 smoothens the mesoscopic hill-like structures, and then, at 1×1012 ions/cm2 new surface structures are created. When the fluence is further increased to 1×1013 ions/cm2 an increase in the surface roughness is observed. The MOKE loop of as prepared film indicated a squareness ratio of 0.62. As the film is irradiated with fluences of 1×1011 ions/cm2, 1×1012 ions/cm2 and 1×1013 ions/cm2 the squareness ratio changes to 0.76, 0.8 and 0.86 respectively. This enhancement in squareness ratio towards 1 is a typical feature when the exchange interaction starts to dominates the inherent anisotropies in the system. The variation in surface magnetisation is explained based on the variations in surface roughness with swift heavy ion (SHI) irradiation.

  13. Investigation on the dielectric response of NdMnO3/LSAT thin films: Effect of 200 MeV Ag+15 ion irradiation

    Science.gov (United States)

    Udeshi, Malay; Vyas, Brinda; Trivedi, Priyanka; Katba, Savan; Ravalia, Ashish; Solanki, P. S.; Shah, N. A.; Asokan, K.; Ojha, S.; Kuberkar, D. G.

    2015-12-01

    We report the results of the modifications in structural and dielectric behaviour of pulsed laser deposited NdMnO3 manganite thin films grown on (1 0 0) single crystalline (LaAlO3)0.3 (Sr2AlTaO6)0.7 substrate irradiated with the 200 MeV Ag+15 ion irradiation having different fluences, ∼5 × 1010, ∼5 × 1011, ∼5 × 1012 ions/cm2. Structural strain was quantified using analysis of X-ray Diffraction data while Rutherford Backscattering measurements were performed on pristine NdMnO3 film to confirm the elemental composition, thickness and oxygen content. Dielectric measurements performed on all the irradiated films show that, the dielectric constant decreases with increase in ion fluence which has been correlated with the irradiation induced increase in strain at the film-substrate interface. The dielectric relaxation behaviour of pristine and irradiated NdMnO3 films have been understood by fitting the dielectric data using the Cole-Cole plots.

  14. 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.

  15. Improved current transport properties of post annealed Y1Ba2Cu3O7-x thin films using Ag doping

    DEFF Research Database (Denmark)

    Clausen, Thomas; Skov, Johannes; Jacobsen, Claus Schelde;

    1996-01-01

    films have a maximum in Jc (77 K) around 250 nm. As for the undoped films, there is a large decrease in Jc (77 K) for Ag doped films with tnom>=300 nm. It was found that the higher values of Jc (77 K) for the Ag doped films were due to a better epitaxial growth of the YBCO compound. The low values of Jc...

  16. Enhancement of wettability and antibiotic loading/release of hydroxyapatite thin film modified by 100 MeV Ag{sup 7+} ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Elayaraja, K. [Crystal Growth Centre, Anna University, Chennai 600 025 (India); Rajesh, P. [Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Poojappura, Thiruvananthapuram 695 012 (India); Ahymah Joshy, M.I.; Sarath Chandra, V.; Suganthi, R.V. [Crystal Growth Centre, Anna University, Chennai 600 025 (India); Kennedy, J. [National Isotope Centre, GNS Science, 30 Gracefield Road, Lower Hutt (New Zealand); Kulriya, P.K.; Sulania, I.; Asokan, K.; Kanjilal, D.; Avasthi, D.K. [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067 (India); Varma, H.K. [Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Poojappura, Thiruvananthapuram 695 012 (India); Narayana Kalkura, S., E-mail: kalkurasn@annauniv.edu [Crystal Growth Centre, Anna University, Chennai 600 025 (India)

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Reduction in particle size on irradiation leading to nanosized HAp. Black-Right-Pointing-Pointer Enhancement of surface roughness and bioactivity on irradiation. Black-Right-Pointing-Pointer Irradiation at lower fluence transforms the surface hydrophobic. Black-Right-Pointing-Pointer The surface turned hydrophilic at higher fluence. Black-Right-Pointing-Pointer Improved drug (amoxicillin) loading on irradiated samples. - Abstract: The effect of swift heavy 100 MeV Ag{sup 7+} ions irradiation was studied on hydroxyapatite (HAp) thin film prepared by pulsed laser deposition technique (PLD). The GIXRD analysis confirmed the absence of any phase in the HAp phase due to irradiation. In addition, there was a considerable decrease in crystallinity and crystallite size on irradiation. There was no significant variation in the stoichiometry of the irradiated films. Irradiation seemed to decrease the optical band gap energy of HAp thin films. The surface roughness, wettability and bioactivity were improved on irradiation of the samples. Amount of amoxicillin loading/release increased (10%) in ion beam irradiated (1 Multiplication-Sign 10{sup 12} ions cm{sup -2}) sample. Irradiated sample showed fast rate of amoxicillin (AMX) release than the pristine. Bactericidal effect was found to increase on irradiation. Surface modified and antibiotics incorporated HAp coated titanium implants may be used to prevent post-surgical infections and to promote bone-bonding of orthopedic devices.

  17. 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...

  18. Multifunctional thin film surface

    Energy Technology Data Exchange (ETDEWEB)

    Brozik, Susan M.; Harper, Jason C.; Polsky, Ronen; Wheeler, David R.; Arango, Dulce C.; Dirk, Shawn M.

    2015-10-13

    A thin film with multiple binding functionality can be prepared on an electrode surface via consecutive electroreduction of two or more aryl-onium salts with different functional groups. This versatile and simple method for forming multifunctional surfaces provides an effective means for immobilization of diverse molecules at close proximities. The multifunctional thin film has applications in bioelectronics, molecular electronics, clinical diagnostics, and chemical and biological sensing.

  19. Photocatalytic Activity of Ag-TiO2 Thin Films by Two Different Modified Methods%两种不同改性方法制备的Ag-TiO2薄膜光催化活性研究

    Institute of Scientific and Technical Information of China (English)

    白亮; 任学昌; 魏雪芬; 李保成; 马学琴

    2011-01-01

    以溶胶凝胶法在平板玻璃表面负载了TiO2薄膜,用不同浓度AgNO3溶液浸渍,然后进行了光照还原法和煅烧分解法Ag改性.以甲醛为模拟污染物,考察了两种方法改性的Ag-TiO2薄膜的光催化活性.结果表明:光照还原法在AgNO3溶液为0.1 moL/L时Ag改性的TiO2薄膜催化活性最强,其催化活性是纯TiC2薄膜的2.3倍;煅烧分解法AgNO3溶液为0.05 moL/L时Ag改性的TiO2薄膜催化活性最强,其催化活性是纯TiO2薄膜的2.9;分析了两种不同改性方法提高TiO2薄膜催化活性的机理.%Ag-TiO2 thin films were prepared as follows :TiO2 thin films were prepared using sol-gel method and subsequently dipped in AgNO3 solution, then they were illuminated and calcined, respectively. The pho-tocatalytic activity of Ag-TiO2 thin films was tested using phenol degradation as the model reaction. The results indicated that when the concentration of AgNO3 solution was 0. 1 moL/L,the photocatalytic activity of the photodeposited Ag-TiO2 thin films was 2. 3 times of that of pure TiO2 thin films,when the concentration of AgNC>3 solution was 0. 05 moL/L,the photocatalytic activity of the calcined Ag-TiO2 thin films was 2. 9 times of that of pure TiO2 thin films. The mechanism of two modification methods to improve activity of TiO2 thin films were analyzed.

  20. Flexible Transparent Electrode of Hybrid Ag-Nanowire/Reduced-Graphene-Oxide Thin Film on PET Substrate Prepared Using H2/Ar Low-Damage Plasma

    Directory of Open Access Journals (Sweden)

    Chi-Hsien Huang

    2017-01-01

    Full Text Available We employ H2/Ar low-damage plasma treatment (H2/Ar-LDPT to reduce graphene oxide (GO coating on a polymer substrate—polyethylene terephthalate (PET—with the assistance of atomic hydrogen (Hα at low temperature of 70 °C. Four-point probing and ultraviolet-visible (UV-Vis spectroscopy demonstrate that the conductivity and transmittance can be controlled by varying the H2/Ar flow rate, treatment time, and radio-frequency (RF power. Optical emission spectroscopy reveals that the Hα intensity depends on these processing parameters, which influence the removal of oxidative functional groups (confirmed via X-ray photoelectron spectroscopy to yield reduced GO (rGO. To further improve the conductivity while maintaining high transmittance, we introduce silver nanowires (AgNWs between rGO and a PET substrate to obtain a hybrid rGO/AgNWs/PET with a sheet resistance of ~100 Ω/sq and 81% transmittance. In addition, the hybrid rGO/AgNWs thin film also shows high flexibility and durability and is suitable for flexible and wearable electronics applications.

  1. Structural Investigation of Photocatalyst Solid Ag1−xCuxInS2 Quaternary Alloys Sprayed Thin Films Optimized within the Lattice Compatibility Theory (LCT Scope

    Directory of Open Access Journals (Sweden)

    A. Colantoni

    2014-01-01

    Full Text Available CuxAg1−xInS2 solid thin films were fabricated through a low-cost process. Particular process-related enhanced properties lead to reaching a minimum of lattice mismatch between absorber and buffer layers within particular solar cell devices. First, copper-less samples X-ray diffraction analysis depicts the presence of AgInS2 ternary compound in chalcopyrite tetragonal phase with privileged (112 peak (d112=1.70 Å according to JCPDS 75-0118 card. Second, when x content increases, we note a shift of the same preferential orientation (112 and its value reaches 1.63 Å corresponding to CuInS2 chalcopyrite tetragonal material according to JCPDS 89-6095 file. Finally, the formation and stability of these quaternaries have been discussed in terms of the lattice compatibility in relation with silver-copper duality within indium disulfide lattice structure. Plausible explanations for the extent and dynamics of copper incorporation inside AgInS2 elaborated ternary matrices have been proposed.

  2. LuAG:Pr, LuAG:La, and LuAP:Ce thin film scintillators for visualisation of x-ray images

    Science.gov (United States)

    Zorenko, Yuriy; Gorbenko, Vitaliy; Voznyak, Taras; Martin, Thierry; Douissard, Paul-Antoine; Mares, Jiri A.; Nikl, Martin

    2009-05-01

    The work is dedicated to investigation of the luminescent properties of UV-emitting single crystalline films (SCF) based on the Lu3Al5O12:La and Lu3Al5O12:Pr garnet and LuAlO3:Ce perovskite compounds grown by liquid phase epitaxy method from the PbO-B2O3 flux onto Y3Al5O12 and YAlO3 substrates, respectively, for testing as scintillation screens in high-resolution microimaging detectors used in applications with synchrotrons radiation. The first image with a spatial resolution of about 1.5 μm of X-ray excited resolution target was obtained using only the UV part of the light of the LuAG:La SCF scintillators. The possible ways for improvement of figure-of-merit of UV emitting SCF scintillators and increase of spatial resolution of the detector are discussed.

  3. Production of BiPbSrCaCuO thin films on MgO and Ag/MgO substrates by electron beam deposition techniques

    CERN Document Server

    Varilci, A; Gorur, O; Celebi, S; Karaca, I

    2002-01-01

    Superconducting BiPbSrCaCuO thin films were prepared on MgO(001) and Ag/MgO substrates using an electron beam (e-beam) evaporation technique. The effects of annealing temperature and Ag diffusion on the crystalline structure and some superconducting properties, respectively, were investigated by X-ray diffraction, atomic force microscopy, and by measurements of the critical temperature and the critical current density. It was shown that an annealing of both types of films at 845 or 860 C resulted in the formation of mixed Bi-2223 and Bi-2212 phases with a high degree of preferential orientation with the c-axis perpendicular to the substrates. The slight increase of the critical temperature from 103 K to 105 K, the enhancement of the critical current density from 2 x 10 sup 3 to 6 x 10 sup 4 A/cm sup 2 , and the improved surface smoothness are due to a possible silver doping from the substrate. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  4. 稀土对金属纳米粒子-介质复合薄膜(Ag-BaO)光电发射性能的增强%ENHANCED PHOTOEMISSION FROM METAL NANOPARTICLE COMPOSITE THIN FILMS (Ag-BaO) DOPED WITH RARE-EARTH ELEMENTS

    Institute of Scientific and Technical Information of China (English)

    许北雪; 吴锦雷; 刘惟敏; 杨海; 邵庆益; 刘盛; 薛增泉; 吴全德

    2001-01-01

    用真空蒸发沉积的方法制备了掺杂稀土的金属纳米粒子-介质复 合薄膜(Ag-BaO薄膜). 与不掺杂稀土的Ag-BaO薄膜相比,其光电发射能力提高了近40%. 透射电镜分析表明,掺杂稀土后,Ag-BaO薄膜中的Ag纳米粒子明显细化、球化、密度增大 . 这表明Ag纳米粒子的细化,使得其在光作用下,光电子更容易通过隧道效应穿过界面位垒 逸出,导致光电发射能力增强.%A metal nanoparticles-composite thin film (Ag-BaO), doped by rare-earth eleme nts, was g rown by vacuum deposition. Compared with the normal Ag-BaO thin film, the photo emission current of the doped Ag-BaO thin film increases by about 40%. The tran smi ssion electron micrograph indicated that Ag nanoparticles become smaller when do ped with rare-earth. With the smaller size of Ag nanoparticles, photoelect rons are eas ier to transgress from Ag nanoparticles via tunnel effect. Thus the photomission current increases.

  5. Study of semiconducting parameters in dark as well as in presence of light for Se90X10 (X=Ag,In) thin films

    Science.gov (United States)

    Singh, N. K.; Kumar, Anjani; Kumar, D.; Shukla, S.

    2016-05-01

    The present paper reports the study of semiconducting parameters (activation energy and pre-exponential factor) in glassy samples of Se90X10 (X= Ag, In) in dark as well as in presence of light. Temperature dependence of dark and photo-conductivity is measured in amorphous thin films in the temperature range 300-378 K and in the intensity range 2000-18000 Lux. A straight line between lnσ0 and ΔE indicates the presence of Meyer - Neldel (MN) rule in dark as well as in presence of light. Linear dependence of ln(σ0) on ΔE in case of amorphous material indicate that the conduction band tails a finite energy distance towards the valence band and a Fermi level which is controlled by fixed dominant hole levels deeper in the gap.

  6. Electrical characterization of Al, Ag and In contacts on CuInS{sub 2} thin films deposited by spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Peza-Tapia, Juan Manuel; Morales-Acevedo, Arturo; Ortega-Lopez, Mauricio [CINVESTAV del IPN, Electrical Engineering Department, Av. IPN No. 2508, Mexico 07360, D.F. (Mexico)

    2009-05-15

    The specific contact resistivity ({rho}{sub C}) for aluminum (Al), silver (Ag) and indium (In) metallic contacts on CuInS{sub 2} thin films was determined from I-V measurements, with the purpose of having the most appropriate ohmic contact for TCO/CdS/CuInS{sub 2} solar cells; {rho}{sub C} was measured using the transmission line method (TLM) for the metallic contacts evaporated on CuInS{sub 2} thin films deposited by spray pyrolysis with ratios x=[Cu]/[In]=1.0, 1.1, 1.3 and 1.5 in the spray solution. The results show that In contacts have the lowest {rho}{sub C} values for CuInS{sub 2} samples grown with x=1.5. The minimum {rho}{sub C} was 0.26 {omega} cm{sup 2} for the In contacts. This value, although not very low, will allow the fabrication of CuInS{sub 2} solar cells with a small series resistance. (author)

  7. Evolution of structural and magnetic properties of Co-doped TiO2 thin films irradiated with 100 MeV Ag7+ ions

    Science.gov (United States)

    Mohanty, P.; Singh, V. P.; Mishra, N. C.; Ojha, S.; Kanjilal, D.; Rath, Chandana

    2014-08-01

    In continuation to our earlier studies where we have shown room temperature ferromagnetism observed in TiO2 and Co-doped TiO2 (CTO) thin films independent of their phase (Mohanty et al 2012 J. Phys. D: Appl. Phys. 45 325301), here the modifications in structure and magnetic properties in CTO thin films using 100 MeV Ag7+ ion irradiation are reported. Owing to the important role of defects in tailoring the magnetic properties of the material, we vary the ion fluence from 5 × 1011 to 1 × 1012 ions cm-2 to create post-deposition defects. While the film deposited under 0.1 mTorr oxygen partial pressure retains its crystallinity showing radiation-resistant behaviour even at a fluence of 1 × 1012 ions cm-2, films deposited under 1 to 300 mTorr oxygen partial pressure becomes almost amorphous at the same fluence. Using Poisson's law, the diameter of the amorphized region surrounding the ion path is calculated to be ˜4.2 nm from the x-ray diffraction peak intensity ((1 1 0) for rutile phase) as a function of ion fluence. The saturation magnetization (Ms) decreases exponentially similar to the decrease in x-ray peak intensity with fluence, indicating magnetic disordered region surrounding the ion path. The diameter of the magnetic disordered region is found to be ˜6.6 nm which is larger than the diameter of the amorphized latent track. Therefore, it is confirmed that swift heavy ion irradiation induces a more significant magnetic disorder than the structural disorder.

  8. Plasmonic modes in thin films: quo vadis?

    Directory of Open Access Journals (Sweden)

    Antonio ePolitano

    2014-07-01

    Full Text Available Herein, we discuss the status and the prospect of plasmonic modes in thin films. Plasmons are collective longitudinal modes of charge fluctuation in metal samples excited by an external electric field. Surface plasmons (SPs are waves that propagate along the surface of a conductor with applications in magneto-optic data storage, optics, microscopy, and catalysis. In thin films the electronic response is influenced by electron quantum confinement. Confined electrons modify the dynamical screening processes at the film/substrate interface by introducing novel properties with potential applications and, moreover, they affect both the dispersion relation of SP frequency and the damping processes of the SP.Recent calculations indicate the emergence of acoustic surface plasmons (ASP in Ag thin films exhibiting quantum well states and in graphene films. The slope of the dispersion of ASP decreases with film thickness. We also discuss open issues in research on plasmonic modes in graphene/metal interfaes.

  9. Functional Ag porous films prepared by electrospinning

    Science.gov (United States)

    Dong, Guoping; Xiao, Xiudi; Liu, Xiaofeng; Qian, Bin; Liao, Yang; Wang, Chen; Chen, Danping; Qiu, Jianrong

    2009-06-01

    Face-centered cubic Ag porous films have been prepared directly from the heat treatment of AgNO 3-doped poly(vinyl alcohol) (PVA) electrospun nanofibers. Using Rhodamine B (RB) as the probing molecule, the surface-enhanced Raman scattering (SERS) effect of Ag porous films was demonstrated. The antibacterial activity of Ag porous films was also studied in this work. The propagation and biological activity of yeast cells were effectively inhibited by Ag porous films. These functional Ag porous films were expected to be applied in many fields, such as catalysis, diagnostics, sensors and antibacterial, etc.

  10. Thin film superfluid optomechanics

    CERN Document Server

    Baker, Christopher G; McAuslan, David L; Sachkou, Yauhen; He, Xin; Bowen, Warwick P

    2016-01-01

    Excitations in superfluid helium represent attractive mechanical degrees of freedom for cavity optomechanics schemes. Here we numerically and analytically investigate the properties of optomechanical resonators formed by thin films of superfluid $^4$He covering micrometer-scale whispering gallery mode cavities. We predict that through proper optimization of the interaction between film and optical field, large optomechanical coupling rates $g_0>2\\pi \\times 100$ kHz and single photon cooperativities $C_0>10$ are achievable. Our analytical model reveals the unconventional behaviour of these thin films, such as thicker and heavier films exhibiting smaller effective mass and larger zero point motion. The optomechanical system outlined here provides access to unusual regimes such as $g_0>\\Omega_M$ and opens the prospect of laser cooling a liquid into its quantum ground state.

  11. Biomimetic thin film deposition

    Science.gov (United States)

    Rieke, P. C.; Campbell, A. A.; Tarasevich, B. J.; Fryxell, G. E.; Bentjen, S. B.

    1991-04-01

    Surfaces derivatized with organic functional groups were used to promote the deposition of thin films of inorganic minerals. These derivatized surfaces were designed to mimic the nucleation proteins that control mineral deposition during formation of bone, shell, and other hard tissues in living organisms. By the use of derivatized substrates control was obtained over the phase of mineral deposited, the orientation of the crystal lattice and the location of deposition. These features are of considerable importance in many technically important thin films, coatings, and composite materials. Methods of derivatizing surfaces are considered and examples of controlled mineral deposition are presented.

  12. Thin film ceramic thermocouples

    Science.gov (United States)

    Gregory, Otto (Inventor); Fralick, Gustave (Inventor); Wrbanek, John (Inventor); You, Tao (Inventor)

    2011-01-01

    A thin film ceramic thermocouple (10) having two ceramic thermocouple (12, 14) that are in contact with each other in at least on point to form a junction, and wherein each element was prepared in a different oxygen/nitrogen/argon plasma. Since each element is prepared under different plasma conditions, they have different electrical conductivity and different charge carrier concentration. The thin film thermocouple (10) can be transparent. A versatile ceramic sensor system having an RTD heat flux sensor can be combined with a thermocouple and a strain sensor to yield a multifunctional ceramic sensor array. The transparent ceramic temperature sensor that could ultimately be used for calibration of optical sensors.

  13. Thin films for material engineering

    Science.gov (United States)

    Wasa, Kiyotaka

    2016-07-01

    Thin films are defined as two-dimensional materials formed by condensing one by one atomic/molecular/ionic species of matter in contrast to bulk three-dimensional sintered ceramics. They are grown through atomic collisional chemical reaction on a substrate surface. Thin film growth processes are fascinating for developing innovative exotic materials. On the basis of my long research on sputtering deposition, this paper firstly describes the kinetic energy effect of sputtered adatoms on thin film growth and discusses on a possibility of room-temperature growth of cubic diamond crystallites and the perovskite thin films of binary compound PbTiO3. Secondly, high-performance sputtered ferroelectric thin films with extraordinary excellent crystallinity compatible with MBE deposited thin films are described in relation to a possible application for thin-film MEMS. Finally, the present thin-film technologies are discussed in terms of a future material science and engineering.

  14. 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.

  15. 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.

  16. 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.

  17. Influence of substrate temperature on certain physical properties and antibacterial activity of nanocrystalline Ag-doped In$_2$O$_3$ thin films

    Indian Academy of Sciences (India)

    P DEEPA; P PHILOMINATHAN

    2016-12-01

    Nanocrystalline Ag-doped indium oxide (AIO) thin films, by employing a much simplified spray pyrolysis technique in different substrate temperatures (300, 350, 400 and 450$\\deg$ C), were fabricated for the first time. The deposited films were subjected to various characterization studies, to explore certain features like the influence of various deposition temperatures on physical and antibacterial properties. XRD results showed that all the samples exhibited preferential orientation along the (2 2 2) plane. The variation in the crystalline size with increasing substrate temperature was explained on the basis of the Zener pinning effect. The electrical sheet resistance ($R_{sh}$) was found to decrease sharply with increasing substrate temperature and attained a minimum value (62$\\Omega$/$\\square$) at 400$\\deg$C and then started increasing for higher deposition temperatures. Further, PL emission spectra of the samples in the visible range ascertained the possibility of applicability of the same in nanoscale optoelectronic devices. From the studies, it was found that at 400.C deposition temperature, one could expect better antibacterial efficiency against {\\it Escherichia coli}. The influence of the shape and size of AIO nanograins on the antibacterial activity was analysed using scanning electron microscopy images.

  18. Selective inorganic thin films

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, M.L.F.; Weisenbach, L.A.; Anderson, M.T. [Sandia National Laboratories, Albuquerque, NM (United States)] [and others

    1995-05-01

    This project is developing inorganic thin films as membranes for gas separation applications, and as discriminating coatings for liquid-phase chemical sensors. Our goal is to synthesize these coatings with tailored porosity and surface chemistry on porous substrates and on acoustic and optical sensors. Molecular sieve films offer the possibility of performing separations involving hydrogen, air, and natural gas constituents at elevated temperatures with very high separation factors. We are focusing on improving permeability and molecular sieve properties of crystalline zeolitic membranes made by hydrothermally reacting layered multicomponent sol-gel films deposited on mesoporous substrates. We also used acoustic plate mode (APM) oscillator and surface plasmon resonance (SPR) sensor elements as substrates for sol-gel films, and have both used these modified sensors to determine physical properties of the films and have determined the sensitivity and selectivity of these sensors to aqueous chemical species.

  19. Silver buffer layers for YBCO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Azoulay, J. [Tel Aviv Univ. (Israel). Center for Technol. Education Holon

    1999-09-01

    A simple economical conventional vacuum system was used for evaporation of YBCO thin films on as-deposited unbuffered Ag layers on MgO substrates. The subsequent heat treatment was carried out in low oxygen partial pressure at a relative low temperature and short dwelling time. The films thus obtained were characterized for electrical properties using dc four probe electrical measurements and inspected for structural properties and chemical composition by scanning electron microscopy (SEM). (orig.)

  20. Reactive combinatorial synthesis and characterization of a gradient Ag-Ti oxide thin film with antibacterial properties.

    Science.gov (United States)

    Unosson, Erik; Rodriguez, Daniel; Welch, Ken; Engqvist, Håkan

    2015-01-01

    The growing demand for orthopedic and dental implants has spurred researchers to develop multifunctional coatings, combining tissue integration with antibacterial features. A possible strategy to endow titanium (Ti) with antibacterial properties is by incorporating silver (Ag), but designing a structure with adequate Ag(+) release while maintaining biocompatibility has been shown difficult. To further explore the composition-structure-property relationships between Ag and Ti, and its effects against bacteria, this study utilized a combinatorial approach to manufacture and test a single sample containing a binary Ag-Ti oxide gradient. The sample, sputter-deposited in a reactive (O2) environment using a custom-built combinatorial physical vapor deposition system, was shown to be effective against Staphylococcus aureus with viability reductions ranging from 17 to above 99%, depending on the amount of Ag(+) released from its different parts. The Ag content along the gradient ranged from 35 to 62 wt.%, but it was found that structural properties such as varied porosity and degree of crystallinity, rather than the amount of incorporated Ag, governed the Ag(+) release and resulting antibacterial activity. The coating also demonstrated in vitro apatite-forming abilities, where structural variety along the sample was shown to alter the hydrophilic behavior, with the degree of hydroxyapatite deposition varying accordingly. By means of combinatorial synthesis, a single gradient sample was able to display intricate compositional and structural features affecting its biological response, which would otherwise require a series of coatings. The current findings suggest that future implant coatings incorporating Ag as an antibacterial agent could be structurally enhanced to better suit clinical requirements.

  1. Microwave characteristics of sol-gel based Ag-doped (Ba{sub 0.6}Sr{sub 0.4})TiO{sub 3} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyoung-Tae; Kim, Cheolbok [Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL 32611 (United States); Senior, David E. [Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL 32611 (United States); Department of Electrical and Electronic Engineering, Universidad Tecnológica de Bolívar Cartagena, 130011 Colombia (Colombia); Kim, Dongsu [Packaging Research Center, Korea Electronics Technology Institute, Gyeonggi-do, 463-816 (Korea, Republic of); Yoon, Yong-Kyu, E-mail: ykyoon@ece.ufl.edu [Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL 32611 (United States)

    2014-08-28

    Dielectric Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3} (BST) thin films with a different concentration of Ag-dopant of 0.5, 1, 1.5, 2, 3, and 5 mol % have been prepared using an alkoxide-based sol-gel method on a Pt(111)/TiO{sub 2}/SiO{sub 2}/Si substrate and their surface morphology and crystallinity have been examined using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis, respectively. An on-chip metal-insulator-metal capacitor has been fabricated with the prepared thin film ferroelectric sample. Concentric coplanar electrodes are used for high frequency electrical characterization with a vector network analyzer and a probe station. The SEM images show that increasing Ag doping concentration leads to a decrease in grain size. XRD reveals that the fabricated films show good BST crystallinity for all the concentration while a doping concentration of 5 mol % starts to show an Ag peak, implying a metallic phase. Improved microwave dielectric loss properties of the BST thin films are observed in a low Ag doping level. Especially, BST with an Ag doping concentration of 1 mol % shows the best properties with a dielectric constant of 269.3, a quality factor of 48.1, a tunability at the electric field of 100 kV/cm of 41.2 %, a leakage-current density of 1.045 × 10{sup −7}A/cm{sup 2} at an electric field of 100 kV/cm and a figure of merit (defined by tunability (%) divided by tan δ (%)) of 19.59 under a dc bias voltage of 10 V at 1 GHz. - Highlights: • High quality Ag-doped Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3} (BST) thin films were derived by the sol-gel method. • Doped Ag replaced the A site ions in the ABO{sub 3} type structure. • Doped Ag helped lower leakage current by filling oxygen vacancies, which is a leakage path. • Microwave characteristics of low dielectric loss and good tunability were confirmed. • Great potential is envisioned for low loss tunable microwave applications.

  2. [Spectral emissivity of thin films].

    Science.gov (United States)

    Zhong, D

    2001-02-01

    In this paper, the contribution of multiple reflections in thin film to the spectral emissivity of thin films of low absorption is discussed. The expression of emissivity of thin films derived here is related to the thin film thickness d and the optical constants n(lambda) and k(lambda). It is shown that in the special case d-->infinity the emissivity of thin films is equivalent to that of the bulk material. Realistic numerical and more precise general numerical results for the dependence of the emissivity on d, n(lambda) and k(lambda) are given.

  3. Pulsed laser deposition of nanostructured Ag films

    Energy Technology Data Exchange (ETDEWEB)

    Donnelly, Tony [School of Physics, Trinity College, Dublin 2 (Ireland); Doggett, Brendan [School of Physics, Trinity College, Dublin 2 (Ireland); Lunney, James G. [School of Physics, Trinity College, Dublin 2 (Ireland)]. E-mail: jlunney@tcd.ie

    2006-04-30

    Ultra-thin (0.5-5 nm) films of Ag have been prepared by pulsed laser deposition in vacuum using a 26 ns KrF excimer laser at 1 J cm{sup -2}. The deposition was controlled using a Langmuir ion probe and a quartz crystal thickness monitor. Transmission electron microscopy showed that the films are not continuous, but are structured on nanometer size scales. Optical absorption spectra showed the expected surface plasmon resonance feature, which shifted to longer wavelength and increased in strength as the equivalent film thickness was increased. It is shown that Maxwell Garnett effective medium theory can be used to calculate the main features of optical absorption spectra.

  4. The novel transparent sputtered p-type CuO thin films and Ag/p-CuO/n-Si Schottky diode applications

    Directory of Open Access Journals (Sweden)

    A. Tombak

    2015-01-01

    Full Text Available In the current paper, the physical properties and microelectronic parameters of direct current (DC sputtered p-type CuO film and diode have been investigated. The film of CuO as oxide and p-type semiconductor is grown onto glass and n-Si substrates by reactive DC sputtering at 250 °C. After deposition, a post-annealing procedure is applied at various temperatures in ambient. Through this research, several parameters are determined such structural, optical and electrical magnitudes. The thickness of CuO thin films goes from 122 to 254 nm. A (111-oriented cubic crystal structure is revealed by X-ray analysis. The grain size is roughly depending on the post-annealing temperature, it increases with temperature within the 144–285 nm range. The transmittance reaches 80% simultaneously in visible and infrared bands. The optical band gap is varied between 1.99 and 2.52 eV as a result of annealing temperature while the resistivity and the charge carrier mobility decrease with an increase in temperature from 135 to 14 Ω cm and 0.92 to 0.06 cm2/Vs, respectively. The surface of samples is homogenous, bright dots are visible when temperature reaches the highest value. As a diode, Ag/CuO/n-Si exhibits a non-ideal behavior and the ideality factor is about 3.5. By Norde method, the barrier height and the series resistance are extracted and found to be 0.96 V and 86.6 Ω respectively.

  5. Thin film superconductor magnetic bearings

    Science.gov (United States)

    Weinberger, Bernard R.

    1995-12-26

    A superconductor magnetic bearing includes a shaft (10) that is subject to a load (L) and rotatable around an axis of rotation, a magnet (12) mounted to the shaft, and a stator (14) in proximity to the shaft. The stator (14) has a superconductor thin film assembly (16) positioned to interact with the magnet (12) to produce a levitation force on the shaft (10) that supports the load (L). The thin film assembly (16) includes at least two superconductor thin films (18) and at least one substrate (20). Each thin film (18) is positioned on a substrate (20) and all the thin films are positioned such that an applied magnetic field from the magnet (12) passes through all the thin films. A similar bearing in which the thin film assembly (16) is mounted on the shaft (10) and the magnet (12) is part of the stator (14) also can be constructed.

  6. Carbon Superatom Thin Films

    Energy Technology Data Exchange (ETDEWEB)

    Canning, A. [Cray Research, PSE, EPFL, 1015 Lausanne (Switzerland); Canning, A.; Galli, G. [Institut Romand de Recherche Numerique en Physique des Materiaux (IRRMA), IN-Ecublens, 1015 Lausanne (Switzerland); Kim, J. [Department of Physics, The Ohio State University, Columbus, Ohio 43210 (United States)

    1997-06-01

    We report on quantum molecular dynamics simulations of C{sub 28} deposition on a semiconducting surface. Our results show that under certain deposition conditions C{sub 28} {close_quote}s act as building blocks on a nanometer scale to form a thin film of nearly defect-free molecules. The C{sub 28} {close_quote}s behave as carbon superatoms, with the majority of them being threefold or fourfold coordinated, similar to carbon atoms in amorphous systems. The microscopic structure of the deposited film supports recent suggestions about the stability of a new form of carbon, the hyperdiamond solid. {copyright} {ital 1997} {ital The American Physical Society}

  7. Chiral atomically thin films

    Science.gov (United States)

    Kim, Cheol-Joo; Sánchez-Castillo, A.; Ziegler, Zack; Ogawa, Yui; Noguez, Cecilia; Park, Jiwoong

    2016-06-01

    Chiral materials possess left- and right-handed counterparts linked by mirror symmetry. These materials are useful for advanced applications in polarization optics, stereochemistry and spintronics. In particular, the realization of spatially uniform chiral films with atomic-scale control of their handedness could provide a powerful means for developing nanodevices with novel chiral properties. However, previous approaches based on natural or grown films, or arrays of fabricated building blocks, could not offer a direct means to program intrinsic chiral properties of the film on the atomic scale. Here, we report a chiral stacking approach, where two-dimensional materials are positioned layer-by-layer with precise control of the interlayer rotation (θ) and polarity, resulting in tunable chiral properties of the final stack. Using this method, we produce left- and right-handed bilayer graphene, that is, a two-atom-thick chiral film. The film displays one of the highest intrinsic ellipticity values (6.5 deg μm-1) ever reported, and a remarkably strong circular dichroism (CD) with the peak energy and sign tuned by θ and polarity. We show that these chiral properties originate from the large in-plane magnetic moment associated with the interlayer optical transition. Furthermore, we show that we can program the chiral properties of atomically thin films layer-by-layer by producing three-layer graphene films with structurally controlled CD spectra.

  8. Biomimetic thin film deposition

    Energy Technology Data Exchange (ETDEWEB)

    Rieke, P.R.; Graff, G.E.; Campbell, A.A.; Bunker, B.C.; Baskaran, S.; Song, L.; Tarasevich, B.J.; Fryxell, G.E.

    1995-09-01

    Biological mineral deposition for the formation of bone, mollusk shell and other hard tissues provides materials scientists with illustrative materials processing strategies. This presentation will review the key features of biomineralization and how these features can be of technical importance. We have adapted existing knowledge of biomineralization to develop a unique method of depositing inorganic thin films and coating. Our approach to thin film deposition is to modify substrate surfaces to imitate the proteins found in nature that are responsible for controlling mineral deposition. These biomimetic surfaces control the nucleation and growth of the mineral from a supersaturated aqueous solution. This has many processing advantages including simple processing equipment, environmentally benign reagents, uniform coating of highly complex shapes, and enhanced adherence of coating. Many different types of metal oxide, hydroxide, sulfide and phosphate materials with useful mechanical, optical, electronic and biomedical properties can be deposited.

  9. THEORETICAL DEPENDENCE OF LONG WAVELENGTH PHOTOEMISSION UPON THE SIZE OF Ag NANOPARTICLES EMBEDDED IN BaO SEMICONDUCTOR THIN FILM

    Institute of Scientific and Technical Information of China (English)

    杨海; 蔡武德; 许北雪; 吴锦雷

    2001-01-01

    The dependence of long wavelength photoemission upon the size of Ag nanoparticles embedded in a BaO semicon- ductor is predicted and discussed theoretically. The calculated results show that the increase in the diameter of the Ag nanoparticle, in the range from 1.5 to 37.0nm, leads to the emergence of a roughly Gaussian form of the photoemission spectra and the peaks become markedly narrower. The results also show that the increase in the diameter of the Agnanoparticle leads to the decrease of the long wavelength threshold. The incident light wavelength corresponding to the peak value of the photoemission gets bigger with the increase of the size of Ag nanoparticles, thus showing a redshift.

  10. Thin film processes

    CERN Document Server

    Vossen, John L

    1978-01-01

    Remarkable advances have been made in recent years in the science and technology of thin film processes for deposition and etching. It is the purpose of this book to bring together tutorial reviews of selected filmdeposition and etching processes from a process viewpoint. Emphasis is placed on the practical use of the processes to provide working guidelines for their implementation, a guide to the literature, and an overview of each process.

  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. Thin film interconnect processes

    Science.gov (United States)

    Malik, Farid

    Interconnects and associated photolithography and etching processes play a dominant role in the feature shrinkage of electronic devices. Most interconnects are fabricated by use of thin film processing techniques. Planarization of dielectrics and novel metal deposition methods are the focus of current investigations. Spin-on glass, polyimides, etch-back, bias-sputtered quartz, and plasma-enhanced conformal films are being used to obtain planarized dielectrics over which metal films can be reliably deposited. Recent trends have been towards chemical vapor depositions of metals and refractory metal silicides. Interconnects of the future will be used in conjunction with planarized dielectric layers. Reliability of devices will depend to a large extent on the quality of the interconnects.

  13. Fabrication of Ag:TiO2 Nanocomposite Thin Films by Sol-Gel Followed by Electron Beam Physical Vapour Deposition Technique

    Directory of Open Access Journals (Sweden)

    Manish Kumar

    2013-01-01

    Full Text Available Ag:TiO2 nanocomposite films have been synthesized by sol-gel method followed by electron beam physical vapour deposition. Targets for this deposition were prepared by a hydraulic press using a powder containing Ag and TiO2 prepared by sol-gel technique. Microstructure, surface, and plasmonic properties of nanocomposite films were studied using glancing angle X-ray diffractometer, atomic force microscopy, field emission secondary electron microscopy, and UV-Vis spectroscopy. Microstructural study reveals that Ag nanoparticles are embedded in TiO2 matrix consisting of mixed phases of anatase and rutile. Size estimation using Scherrer formula reveals that average crystallite size of Ag nanoparticles is 23 nm. Surface morphological studies indicate that deposited films are uniform and intact to the substrate and have very low value of root mean square roughness. Optical studies exhibit a surface plasmon resonance induced absorption band in visible region, which is the characteristic feature of Ag nanoparticles. The intensity of this absorption band is found to increase with the increase in deposition time. Multiple peaks observed in absorption band were explained using the concepts of extended Mie scattering. Preliminary experiments also suggested that these nanocomposite films exhibit promising photocatalytic properties, which can be used for water treatment.

  14. 银基复合透明导电薄膜作为薄膜太阳能电池前电极的研究%The research on Ag/TCO tandem film front electrode for thin film solar cells

    Institute of Scientific and Technical Information of China (English)

    陈宇; 曾祥斌; 陈晓晓

    2015-01-01

    An Ag/TCO tandem film are used as front electrode of thin film solar cells, which are composed of super thin Ag film and a textured thin TCO film. This Ag/TCO tandem film has the advantage of high transparency and high conductivity of super thin Ag film. Meanwhile, it solved the laser scribing problems when use Ag film as front electrode in the industry manufacturing processes of thin film solar cells. In experimental, 9 glasses with different thickness SnO2:F film on it are deposited 3/, optical transparent 89%, thickness in 10-15nm super thin Ag film with DC magnet sputtering technology. And these samples are manufactured as a-Si thin film solar panels in same processes. The result shows that when the SnO2:F film have a 80/ sheet resistance it could get the best performance in a-Si solar cells with 4% increase in output power than traditional a-Si solar cells.%提出采用超薄银薄膜和具有陷光结构的薄TCO薄膜组成的复合膜层作为薄膜太阳能电池前电极,有效利用了超薄银膜的高电导性、高透过性,并解决了单银膜无法制作陷光结构以及在产业化生产过程中存在的激光选择性刻划问题。实验采用直流磁控溅射法在9个不同厚度的SnO2:F薄膜导电玻璃上制备方阻为3/,透过率为89%,厚度为10-15nm的超薄银膜构成前电极,并采用相同的工艺制作成单节的非晶硅薄膜太阳能电池组件,结果表明,方阻为80/的SnO2:F薄膜与超薄银膜构成的前电极能获得最佳的非晶硅薄膜太阳能电池输出性能,相比于普通的非晶硅薄膜太阳能电池输出功率提升了4%。

  15. Studies on photocatalytic activity of Ag/TiO2 films

    Institute of Scientific and Technical Information of China (English)

    Hou Xinggang; Wu Xiaoling; Liu Andong

    2006-01-01

    Ag/TiO2 photocatalytic films were produced by hybrid sol-gel method.The photocatalytic degradation of methyl orange (MO) in aqueous solution under 365 nm irradiation on TiO2 and Ag/TiO2 thin films was investigated.The state and amount of Ag species within the film and the enhancement mechanism of photocatalytic activity of Ag/TiO2 were discussed.With a loading molar ratio of Ag/Ti = 0.135 in TiO2 film,the maximum catalytic efficiency was observed.

  16. Thin film tin oxide-based propane gas sensors

    Energy Technology Data Exchange (ETDEWEB)

    Carbajal-Franco, G.; Tiburcio-Silver, A. [Inst. Tecnologico de Toluca, Metepec (Mexico); Dominguez, J.M. [Instituto Mexicano del Petroleo, Apdo. postal 14-805, 07730, D. F., Mexico (Mexico); Sanchez-Juarez, A. [CIE-UNAM, Apdo. postal 34, 62580, Temixco (Mexico)

    2000-09-03

    In this work, we report on the elaboration of SnO{sub 2} and SnO{sub 2}:Ag thin films ({proportional_to}200 nm in thickness) obtained by heat-treatment in oxygen of Sn and Sn:Ag thin films deposited by vacuum evaporation on alumina substrates. A simple and very cheap procedure was used to dope the SnO{sub 2} films with Ag. Preliminary results on the sensing properties of these films are presented. Films are able to detect selectively the presence of C{sub 3}H{sub 8} in the LP-gas domestic mixture. Doping with Ag allows reductions in the optimal operation temperature of the SnO{sub 2} sensors by 100 C. This a very important result when detecting such a highly explosive gas. (orig.)

  17. Investigation on Silicon Thin Film Solar Cells

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The preparation, current status and trends are investigated for silicon thin film solar cells. The advantages and disadvantages of amorphous silicon thin film, polycrystalline silicon thin film and mono-crystalline silicon thin film solar cells are compared. The future development trends are pointed out. It is found that polycrystalline silicon thin film solar cells will be more promising for application with great potential.

  18. Nonlinear optical thin films

    Science.gov (United States)

    Leslie, Thomas M.

    1993-01-01

    A focused approach to development and evaluation of organic polymer films for use in optoelectronics is presented. The issues and challenges that are addressed include: (1) material synthesis, purification, and the tailoring of the material properties; (2) deposition of uniform thin films by a variety of methods; (3) characterization of material physical properties (thermal, electrical, optical, and electro-optical); and (4) device fabrication and testing. Photonic materials, devices, and systems were identified as critical technology areas by the Department of Commerce and the Department of Defense. This approach offers strong integration of basic material issues through engineering applications by the development of materials that can be exploited as the active unit in a variety of polymeric thin film devices. Improved materials were developed with unprecedented purity and stability. The absorptive properties can be tailored and controlled to provide significant improvement in propagation losses and nonlinear performance. Furthermore, the materials were incorporated into polymers that are highly compatible with fabrication and patterning processes for integrated optical devices and circuits. By simultaneously addressing the issues of materials development and characterization, keeping device design and fabrication in mind, many obstacles were overcome for implementation of these polymeric materials and devices into systems. We intend to considerably improve the upper use temperature, poling stability, and compatibility with silicon based devices. The principal device application that was targeted is a linear electro-optic modulation etalon. Organic polymers need to be properly designed and coupled with existing integrated circuit technology to create new photonic devices for optical communication, image processing, other laser applications such as harmonic generation, and eventually optical computing. The progression from microscopic sample to a suitable film

  19. 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

  20. Preparation and characterization of ultra-thin films containing Au and Ag nanoparticles using layer-by-layer deposition technique

    OpenAIRE

    Cönger, Can Pınar

    2009-01-01

    Ankara : The Department of Chemistry and the Institute of Engineering and Sciences of Bilkent University, 2009. Thesis (Master's) -- Bilkent University, 2009. Includes bibliographical references leaves 69-77. The main objective of this thesis is to investigate the layer-by-layer deposited polyelectrolyte and polyelectrolyte/metal nanoparticle films by using X-ray Photoelectron (XPS) and Optical Spectroscopy (UV-Vis). Within this purpose, in the first part of the study, laye...

  1. Light regulated I-V hysteresis loop of Ag/BiFeO3/FTO thin film

    Science.gov (United States)

    Wei, Lujun; Sun, Bai; Zhao, Wenxi; Li, Hongwei; Chen, Peng

    2017-01-01

    A hysteresis loop of current-voltage characteristics based multiferroic BiFeO3 nanoribbons memory device is observed. Moreover, the white-light can greatly regulate both the current-voltage hysteresis loop and the ferroelectric hysteresis loop. The stored space charges within the electrodes/BiFeO3 interface can lead to hysteresis-type I-V characteristics of Ag/BiFeO3/FTO devices. The white-light controlled I-V loop and ferroelectric loop result from photon-generated carries. Since the I-V hysteresis loop and ferroelectric hysteresis loop have a potential application prospect to the memory devices, these two white-light controlled the hysteresis loops curves are likely to provide promising opportunity for developing the multi-functional memory devices.

  2. Effect of BaZrO3/Ag hybrid doping to the microstructure and performance of fluorine-free MOD method derived YBa2Cu3O7−x superconducting thin films

    DEFF Research Database (Denmark)

    Tang, Xiao; Yue, Zhao; Wu, W.

    2015-01-01

    It is known that BaZrO3 and Ag can improve the magnetic and transport performance of YBCO thin film through totally disparate ways. BaZrO3 plays the role of flux pinning centers and Ag improves the transparency of the YBCO grain boundaries. However, similar research is rare on the fluorine-free d...

  3. Studies on structural, electrical and optical properties of multiferroic (Ag, Ni and In) codoped Bi{sub 0.9}Nd{sub 0.1}FeO{sub 3} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Xu, E-mail: xuexu9@163.com; Tan, Guoqiang, E-mail: tan3114@163.com; Dong, Guohua; Liu, Wenlong; Ren, Huijun

    2014-02-15

    Effects of rare earth Nd and (Ag, Ni and In) ions codoping on the structural, electrical, optical, ferroelectric and magnetic properties of the BiFeO{sub 3} (BFO) thin films prepared on FTO/glass substrates by using a sol–gel method were investigated. From X-ray diffraction and Raman scattering analyses, distorted rhombohedral perovskite structures were observed for all the films. The X-ray photoelectron spectroscopy analysis was carried out to investigate the chemical states and lattice deficiencies of the films. Both charge states 3+ and 2+ of Fe ions are simultaneously present in all the films but 2+ state appears to be dominant. The leakage mechanisms of the films were systematically investigated by two kinds of bulk-limited conductions (space-charge-limited conduction and Poole–Frenkel emission) and two kinds of interface-limited conductions (Schottky emission and Fowler–Nordheim tunneling). The optical measurement showed that all the films have a conspicuous absorption in the blue and green light region with the band gap values around 2.7 eV. The present work reveals that the non-magnetically active Ag and In ions are more helpful than the magnetically active Ni ion in enhancing the macroscopic magnetization of BFO by the introduction of a local ferromagnetic coupling rather than an antiferromagnetic one.

  4. Optical properties of rubrene thin film prepared by thermal evaporation

    Institute of Scientific and Technical Information of China (English)

    陈亮; 邓金祥; 孔乐; 崔敏; 陈仁刚; 张紫佳

    2015-01-01

    Rubrene thin films are deposited on quartz substrates and silver nanoparticles (Ag NPs) films by the thermal evapo-ration technique. The optical properties of rubrene thin film are investigated in a spectral range of 190 nm–1600 nm. The analysis of the absorption coefficient (α) reveals direct allowed transition with a corresponding energy of 2.24 eV. The photoluminescence (PL) peak of the rubrene thin film is observed to be at 563 nm (2.21 eV). With the use of Ag NPs which are fabricated by radio-frequency (RF) magnetron sputtering on the quartz, the PL intensity is 8.5 times that of as-deposited rubrene thin film. It is attributed to the fact that the surface plasmon enhances the photoluminescence.

  5. Thin Film Inorganic Electrochemical Systems.

    Science.gov (United States)

    1995-07-01

    determined that thin film cathodes of LiCoO2 can be readily performed by either spray pyrolysis or spin coating . These cathodes are electrochemically...active. We have also determined that thin film anodes of Li4Ti5O12 can be prepared by spray pyrolysis or spin coating . These anodes are also

  6. Synthesis and resistive switching behaviour of ZnMnO3 thin films with an Ag/ZnMnO3/ITO unsymmetrical structure

    Indian Academy of Sciences (India)

    Hua Wang; Shu-Ming Gao; Ji-Wen Xu; Chang-Lai Yuan; Xiao-Wen Zhang

    2015-02-01

    Single-phase MnZnO3 films were prepared on glass substrates coated with the use of indium tin oxide (ITO) as transparent bottom electrode via the sol–gel method. The effects of annealing temperature on structure, resistance switching behaviour and endurance characteristics of the ZnMnO3 films were investigated. The stable resistive switching behaviour with high resistance ratio in Ag/ZnMnO3/ITO unsymmetrical structure was observed. No second phase is detected, and the crystallinity of the MnZnO3 films is improved with the increase in annealing temperature from 350 to 400°C. The MnZnO3 films annealed at 350–450°C with an Ag/MnZnO3/ITO structure exhibit bipolar resistive switching behaviour. Ohmic and space-charge-limited conductions are the dominant mechanisms at low and high resistance states, respectively. $V{}_{\\text{ON}},\\ \\text{V_{OFF}}$ and $R_{\\text{HRS}}/R_{\\text{LRS}}$ of theMnZnO3 films increase with the increase in annealing temperature. Improved endurance characteristics are observed in the samples annealed at 350 and 400°C. The endurance of the MnZnO3 films degrades when annealed at >450°C.

  7. Improving Efficiency of Evaporated Cu2ZnSnS4 Thin Film Solar Cells by a Thin Ag Intermediate Layer between Absorber and Back Contact

    Directory of Open Access Journals (Sweden)

    Hongtao Cui

    2015-01-01

    Full Text Available A 20 nm Ag coating on Mo back contact was adopted to improve the back contact of evaporated Cu2ZnSnS4 (CZTS solar cells. The Ag layer helped reduce the thickness of MoS2 which improves fill factor (FF significantly; additionally, it reduced secondary phases ZnS and SnS2−x, which may help carrier transport; it was also involved in the doping of the absorber layer, which compensated the intrinsic p-type doping and therefore drags down the doping level. The doping involvement may enlarge the depletion region and improve lifetime of the absorber, which led to enhancing open circuit voltage (VOC, short circuit current density (JSC, and efficiency significantly. However, it degrades the crystallinity of the material slightly.

  8. Quantum-well-induced ferromagnetism in thin films

    DEFF Research Database (Denmark)

    Niklasson, A.M.N.; Mirbt, S.; Skriver, Hans Lomholt;

    1997-01-01

    We have used a first-principles Green's-function technique to investigate the magnetic properties of thin films of Rh, Pd, and Pt deposited on a fee Ag (001) substrate. We find that the magnetic moment of the film is periodically suppressed and enhanced as a function of film thickness....... The phenomenon is explained in terms of quantum-well states moving through the Fermi level with increasing film thickness....

  9. Polyimide Aerogel Thin Films

    Science.gov (United States)

    Meador, Mary Ann; Guo, Haiquan

    2012-01-01

    Polyimide aerogels have been crosslinked through multifunctional amines. This invention builds on "Polyimide Aerogels With Three-Dimensional Cross-Linked Structure," and may be considered as a continuation of that invention, which results in a polyimide aerogel with a flexible, formable form. Gels formed from polyamic acid solutions, end-capped with anhydrides, and cross-linked with the multifunctional amines, are chemically imidized and dried using supercritical CO2 extraction to give aerogels having density around 0.1 to 0.3 g/cubic cm. The aerogels are 80 to 95% porous, and have high surface areas (200 to 600 sq m/g) and low thermal conductivity (as low as 14 mW/m-K at room temperature). Notably, the cross-linked polyimide aerogels have higher modulus than polymer-reinforced silica aerogels of similar density, and can be fabricated as both monoliths and thin films.

  10. Optical Properties of Semiconductor-Metal Composite Thin Films in the Infrared Region

    Science.gov (United States)

    Nagendra, C. L.; Lamb, James L.

    1993-01-01

    Germanium:Silver (Ge:Ag) composite thin films having different concentrations of Ag, ranging from 7% to 40% have been prepared by dc co-sputtering of Ge an Ag and the films' surface morphology and optical properties have been characterized using transmission electron microscopy (TEM) and infrared spectrophotometry. It is seen that while the films containing lower concentrations of Ag have island-like morphology (i.e. Ag particles distributed in a Ge matrix), the higher metallic concentration films tend to have symmetric distribution of Ag and Ge.

  11. Grain size and film thickness effect on the thermal expansion coefficient of FCC metallic thin films.

    Science.gov (United States)

    Hwang, Seulgi; Kim, Youngman

    2011-08-01

    Thin films are used in wide range of applications in industry, such as solar cells and LEDs. When thin films are deposited on substrates, various stresses are generated due to the mechanical difference between the film and substrate. These stresses can cause defects, such as cracking and buckling. Therefore, knowledge of the mechanical properties is important for improving their reliability and stability. In this study, the thermal expansion coefficient of FCC metallic thin films, such as Ag and Cu, which have different grain sizes and thicknesses, were calculated using the thermal cycling method. As a result, thermal expansion coefficient increased with increasing grain size. However, the film thickness had no remarkable effect.

  12. A study on 120 MeV Ag{sup 9+} irradiation induced modifications in structural, electrical and optical behavior of ZnSnO{sub 3} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kumaravel, R., E-mail: kumara_03@yahoo.com [Department of Physics, Annapoorana Engineering College, Salem 636 308 (India); Crystal Growth and Thin Film Laboratory, School of Physics, Bharathidasan University, Tiruchirappalli 620 024 (India); Ramamurthi, K. [Crystal Growth and Thin Film Laboratory, School of Physics, Bharathidasan University, Tiruchirappalli 620 024 (India); Sulania, Indra; Asokan, K.; Kanjilal, D.; Avasti, D.K. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110 067 (India)

    2012-08-15

    Spray deposited ZnSnO{sub 3} thin films have been irradiated with 120 MeV Ag{sup 9+} ions at the fluence of 1 Multiplication-Sign 10{sup 12} and 1 Multiplication-Sign 10{sup 13} ions cm{sup -2}. The structural, electrical and optical properties of the pristine and irradiated films were studied using X-ray diffraction, atomic force microscopy, optical transmittance and Hall measurement system. X-ray diffraction studies revealed that the film is amorphized at higher ion fluence. The AFM study of the films implied that roughness of the pristine film increases from 14 to 19 nm after the irradiation. A minimum resistivity of 3.31 Multiplication-Sign 10{sup -2} {Omega} cm and maximum carrier concentration of 1.31 Multiplication-Sign 10{sup 19} cm{sup -3} have been achieved when the film was irradiated with the fluence of 1 Multiplication-Sign 10{sup 13} ions cm{sup -2}. The band gap value decreases from 3.60 to 3.13 eV for the film irradiated with 1 Multiplication-Sign 10{sup 13} ions cm{sup -2}.

  13. Structural and optical characterization of Ag photo-doped thin As40S60 - xSex films for non-linear applications

    Science.gov (United States)

    Tasseva, J.; Todorov, R.; Babeva, Tz; Petkov, K.

    2010-06-01

    This paper deals with the structure and the optical properties of thin As40S60 - xSex films doped with silver. The refractive index n and the optical band gap Egopt were calculated from the transmittance and reflectance spectra. The results showed that the photo-doping leads to increase in the refractive index by about 0.25-0.27. An effect of thickness expansion was observed in the photo-doped layers. The non-linear refractive index, γ, and the two-photon absorption coefficient, β, were evaluated by applying a formula developed by Sheik-Bahae. Each of the films studied exhibits a highly non-linear refractive index at the telecommunication wavelength, 70-850 times higher than that measured for fused silica. From the Raman spectra of thin As40S30Se30 it might be concluded that under dissolution, the silver interacts with both sulfur and selenium. The surface of the thin films was investigated by using a white light interferometric profiler. It was found that the increase in the thickness of the silver layer results in roughening of the surface of the photo-doped films.

  14. Comparison of optical transients during the picosecond laser pulse-induced crystallization of GeSbTe and AgInSbTe phase-change thin films: Nucleation-driven versus growth-driven processes

    Science.gov (United States)

    Liang, Guangfei; Li, Simian; Huang, Huan; Wang, Yang; Lai, Tianshu; Wu, Yiqun

    2013-09-01

    Direct comparison of the real-time in-situ crystallization behavior of as-deposited amorphous Ge2Sb2Te5 (GeSbTe) and Ag8In14Sb55Te23 (AgInSbTe) phase-change thin films driven by picosecond laser pulses was performed by a time-resolved optical pump-probe technique with nanosecond resolution. Different optical transients showed various crystallization processes because of the dissimilar nucleation- and growth-dominated mechanisms of the two materials. The effects of laser pulse fluence, thermal conductive structure, and successive pulse irradiation on their crystallization dynamics were also discussed. A schematic was then established to describe the different crystallization processes beginning from the as-deposited amorphous state. The results may provide further insight into the phase-change mechanism under extra-non-equilibrium conditions and aid the development of ultrafast phase-change memory materials.

  15. 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 t

  16. Raman spectroscopy of chalcogenide thin films prepared by PLD

    Energy Technology Data Exchange (ETDEWEB)

    Erazu, M.; Rocca, J. [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, Universidad de Buenos Aires - CONICET, Paseo Colon 850, 1063 Buenos Aires (Argentina); Fontana, M., E-mail: merazu@fi.uba.a [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, Universidad de Buenos Aires - CONICET, Paseo Colon 850, 1063 Buenos Aires (Argentina); Urena, A.; Arcondo, B. [Laboratorio de Solidos Amorfos, INTECIN, Facultad de Ingenieria, Universidad de Buenos Aires - CONICET, Paseo Colon 850, 1063 Buenos Aires (Argentina); Pradel, A. [ICG, UMR 5253 CNRS UM 2 ENSCM UM1 equipe PMDP CC3, Universite Montpellier 2, 34095 Montpellier Cedex 5 (France)

    2010-04-16

    Chalcogenide glasses have many technological applications as a result of their particular optical and electrical properties. Ge-Se and Ag-Ge-Se systems were recently studied and tested as new materials for building non-volatile memories. Following these ideas, thin films of Ge-Se and Ag-Ge-Se were deposited using pulsed laser deposition (PLD). Ag was sputtered over binary films (for a composition between 0.05 and 0.25 Ag atomic fraction) and photo-diffused afterwards. Thus, three kinds of samples were analyzed by means of Raman spectroscopy, in order to provide information on the short- and medium-range order: PLD binary films before Ag doping, after Ag doping and PLD ternary films. Before Ag doping, binary films exhibited Ge-Se corner-sharing tetrahedra modes at 190 cm{sup -1}, low scattering from edge-sharing tetrahedra at 210 cm{sup -1}, and Se chains at 260 cm{sup -1} (stretching mode). However, after the diffusion process was complete, we observed an intensity reduction of bands centered at 210 cm{sup -1} and 260 cm{sup -1}. The spectra of the photo-diffused films were similar to those of films deposited using a ternary target. Relaxation effects in binary glasses were also analyzed. Results were compared with those of other authors.

  17. Size effects in thin films

    CERN Document Server

    Tellier, CR; Siddall, G

    1982-01-01

    A complete and comprehensive study of transport phenomena in thin continuous metal films, this book reviews work carried out on external-surface and grain-boundary electron scattering and proposes new theoretical equations for transport properties of these films. It presents a complete theoretical view of the field, and considers imperfection and impurity effects.

  18. Thin film corrosion. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Raut, M.K.

    1980-06-01

    Corrosion of chromium/gold (Cr/Au) thin films during photolithography, prebond etching, and cleaning was evaluated. Vapors of chromium etchant, tantalum nitride etchant, and especially gold etchant were found to corrosively attack chromium/gold films. A palladium metal barrier between the gold and chromium layers was found to reduce the corrosion from gold etchant.

  19. Ag3PO4/Ni纳米薄膜降解罗丹明B的光电催化性能和反应机理%Photoelectrocatalytic property and reaction mechanism of Ag3PO4/Ni nano thin film for degrading rhodamine B

    Institute of Scientific and Technical Information of China (English)

    李爱昌; 赵娣; 刘盼盼; 孙少敏; 刘萌

    2015-01-01

    Ag3PO4/Ni thin films were prepared by electrochemical method. The surface morphology, phase structure, optical characteristics and band structure of the thin film were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS), respectively. The photoelectrocatalytic properties and stability of this coating were evaluated with rhodamine B(RhB) as a model compound. Through adding active species scavenger and removing oxygen with nitrogen to the solution, the mechanism of photoelectrocatalytic degradation of the film was explored. The mechanisms of photoeletrocatalytic reaction on the film for RhB under visible irradiation were inputted. The results show that, under optimum conditions, the Ag3PO4/Ni thin film prepared is composed of nano particles and it has dense and layered surface structure. The film has high photoelectrocatalytic activity. At optimum anodic bias, the photoeletrocatalytic degradation rate of Ag3PO4/Ni thin film is 6.69 times as that of porous P25 TiO2 /ITO nanofilm. Compared the coating without anodic bias, the photoeletrocatalytic degradation rate for the Ag3PO4/Ni thin film to RhB increases by 5.34 times and the thin film has obvious photoelectric synergistic effect. Especially, the film has excellent photocatalytic and photoelectrocatalytic stability. At 0.1 V anodic bias, its photoeletrocatalytic stability increases by about one time than its photocatalytic stability without anodic bias.%采用电化学方法制备 Ag3PO4/Ni 薄膜,以扫描电镜(SEM)、X 射线衍射(XRD)和紫外-可见漫反射光谱(UV-Vis DRS)对薄膜的表面形貌、晶相结构、光谱特性及能带结构进行表征,以罗丹明B为模拟污染物对薄膜的光电催化活性和稳定性进行测定,采用向溶液中加入活性物种捕获剂和通氮除氧方法对薄膜的光催化降解机理进行探索,并提出光电催化降解罗丹明B的反应机理.结果表明:最佳工艺下制备的Ag

  20. Thin Film Deposition Techniques (PVD)

    Science.gov (United States)

    Steinbeiss, E.

    The most interesting materials for spin electronic devices are thin films of magnetic transition metals and magnetic perovskites, mainly the doped La-manganites [1] as well as several oxides and metals for passivating and contacting the magnetic films. The most suitable methods for the preparation of such films are the physical vapor deposition methods (PVD). Therefore this report will be restricted to these deposition methods.

  1. Thin Film Encapsulation of Light-Emitting Diodes with Photopolymerized Polyacrylate and Silver Films

    Institute of Scientific and Technical Information of China (English)

    WANG Li-Duo; WU Zhao-Xin; LI Yang; QIU Yong

    2005-01-01

    @@ A thin film encapsulation of organic light-emitting diodes (OLEDs) is investigated with a multi-layer stack of polyacrylate-Ag-polyacrylate-Ag-polyacrylate-Ag-polyacrylate (PAPAPAP). It is shown that the fabrication of polyacrylate films by a wet process does not affect the electroluminescent (EL) characteristics of the devices and polyacrylate films together with the silver layers can perform to minimize oxygen and water diffusion into the organic light-emitting device. The structure of polyacrylate(20 μm)-Ag(200nm)-polyacrylate(20 μm)-Ag(200nm)-polyacrylate(20μm)-Ag(200nm)-polyacrylate(20μm) is demonstrated to enhance dramatically the lifetime of OLEDs.

  2. Thin-film metal hydrides.

    Science.gov (United States)

    Remhof, Arndt; Borgschulte, Andreas

    2008-12-01

    The goal of the medieval alchemist, the chemical transformation of common metals into nobel metals, will forever be a dream. However, key characteristics of metals, such as their electronic band structure and, consequently, their electric, magnetic and optical properties, can be tailored by controlled hydrogen doping. Due to their morphology and well-defined geometry with flat, coplanar surfaces/interfaces, novel phenomena may be observed in thin films. Prominent examples are the eye-catching hydrogen switchable mirror effect, the visualization of solid-state diffusion and the formation of complex surface morphologies. Thin films do not suffer as much from embrittlement and/or decrepitation as bulk materials, allowing the study of cyclic absorption and desorption. Therefore, thin-metal hydride films are used as model systems to study metal-insulator transitions, for high throughput combinatorial research or they may be used as indicator layers to study hydrogen diffusion. They can be found in technological applications as hydrogen sensors, in electrochromic and thermochromic devices. In this review, we discuss the effect of hydrogen loading of thin niobium and yttrium films as archetypical examples of a transition metal and a rare earth metal, respectively. Our focus thereby lies on the hydrogen induced changes of the electronic structure and the morphology of the thin films, their optical properties, the visualization and the control of hydrogen diffusion and on the study of surface phenomena and catalysis.

  3. Birefringent non-polarizing thin film design

    Institute of Scientific and Technical Information of China (English)

    QI Hongji; HONG Ruijin; HE Hongbo; SHAO Jianda; FAN Zhengxiu

    2005-01-01

    In this paper, 2×2 characteristic matrices of uniaxially anisotropic thin film for extraordinary and ordinary wave are deduced at oblique incidence. Furthermore, the reflectance and transmittance of thin films are calculated separately for two polarizations, which provide a new concept for designing non-polarizing thin films at oblique incidence. Besides, using the multilayer birefringent thin films, non-polarizing designs, such as beam splitter thin film at single wavelength, edge filter and antireflection thin film over visible spectral region are obtained at oblique incidence.

  4. Drying of thin colloidal films

    Science.gov (United States)

    Routh, Alexander F.

    2013-04-01

    When thin films of colloidal fluids are dried, a range of transitions are observed and the final film profile is found to depend on the processes that occur during the drying step. This article describes the drying process, initially concentrating on the various transitions. Particles are seen to initially consolidate at the edge of a drying droplet, the so-called coffee-ring effect. Flow is seen to be from the centre of the drop towards the edge and a front of close-packed particles passes horizontally across the film. Just behind the particle front the now solid film often displays cracks and finally the film is observed to de-wet. These various transitions are explained, with particular reference to the capillary pressure which forms in the solidified region of the film. The reasons for cracking in thin films is explored as well as various methods to minimize its effect. Methods to obtain stratified coatings through a single application are considered for a one-dimensional drying problem and this is then extended to two-dimensional films. Different evaporative models are described, including the physical reason for enhanced evaporation at the edge of droplets. The various scenarios when evaporation is found to be uniform across a drying film are then explained. Finally different experimental techniques for examining the drying step are mentioned and the article ends with suggested areas that warrant further study.

  5. Thin-film forces in pseudoemulsion films

    Energy Technology Data Exchange (ETDEWEB)

    Bergeron, V.; Radke, C.J. [California Univ., Berkeley, CA (United States). Dept. of Chemical Engineering]|[Lawrence Berkeley Lab., CA (United States)

    1991-06-01

    Use of foam for enhanced oil recovery (EOR) has shown recent success in steam-flooding field applications. Foam can also provide an effective barrier against gas coning in thin oil zones. Both of these applications stem from the unique mobility-control properties a stable foam possesses when it exists in porous media. Unfortunately, oil has a major destabilizing effect on foam. Therefore, it is important for EOR applications to understand how oil destroys foam. Studies all indicate that stabilization of the pseudoemulsion film is critical to maintain foam stability in the presence of oil. Hence, to aid in design of surfactant formulations for foam insensitivity to oil the authors pursue direct measurement of the thin-film or disjoining forces that stabilize pseudoemulsion films. Experimental procedures and preliminary results are described.

  6. YBCO thin film evaporation on as-deposited silver film on MgO

    Science.gov (United States)

    Azoulay, J.

    1999-11-01

    YBa 2Cu 3O 7- δ (YBCO) thin film was evaporated on as-deposited Ag buffer layer on MgO substrate. A simple, inexpensive vacuum system equipped with one resistively heated source was used. The subsequent heat treatment was carried out under low oxygen partial pressure at a relatively low temperature and short dwelling time. The films thus obtained were characterized for electrical properties using DC four-probe electrical measurements and inspected for structural properties and chemical composition by scanning electron microscopy (SEM). It is shown that YBCO thin film can grow on as-deposited thin silver layer on MgO substrate.

  7. Thin films under chemical stress

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The goal of work on this project has been develop a set of experimental tools to allow investigators interested in transport, binding, and segregation phenomena in composite thin film structures to study these phenomena in situ. Work to-date has focuses on combining novel spatially-directed optical excitation phenomena, e.g. waveguide eigenmodes in thin dielectric slabs, surface plasmon excitations at metal-dielectric interfaces, with standard spectroscopies to understand dynamic processes in thin films and at interfaces. There have been two main scientific thrusts in the work and an additional technical project. In one thrust we have sought to develop experimental tools which will allow us to understand the chemical and physical changes which take place when thin polymer films are placed under chemical stress. In principle this stress may occur because the film is being swelled by a penetrant entrained in solvent, because interfacial reactions are occurring at one or more boundaries within the film structure, or because some component of the film is responding to an external stimulus (e.g. pH, temperature, electric field, or radiation). However all work to-date has focused on obtaining a clearer understanding penetrant transport phenomena. The other thrust has addressed the kinetics of adsorption of model n-alkanoic acids from organic solvents. Both of these thrusts are important within the context of our long-term goal of understanding the behavior of composite structures, composed of thin organic polymer films interspersed with Langmuir-Blodgett (LB) and self-assembled monolayers. In addition there has been a good deal of work to develop the local technical capability to fabricate grating couplers for optical waveguide excitation. This work, which is subsidiary to the main scientific goals of the project, has been successfully completed and will be detailed as well. 41 refs., 10 figs.

  8. Thin-film solar cell

    OpenAIRE

    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 the light-collecting surface. In this context, the relationships 45 < alpha < 135 degrees and 45 < beta < 135 degrees apply. The invention also relates to a panel provided with a plurality of such t...

  9. Scanning tunneling spectroscopy of Pb thin films

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Michael

    2010-12-13

    The present thesis deals with the electronic structure, work function and single-atom contact conductance of Pb thin films, investigated with a low-temperature scanning tunneling microscope. The electronic structure of Pb(111) thin films on Ag(111) surfaces is investigated using scanning tunneling spectroscopy (STS). Quantum size effects, in particular, quantum well states (QWSs), play a crucial role in the electronic and physical properties of these films. Quantitative analysis of the spectra yields the QWS energies as a function of film thickness, the Pb bulk-band dispersion in {gamma}-L direction, scattering phase shifts at the Pb/Ag interface and vacuum barrier as well as the lifetime broadening at anti {gamma}. The work function {phi} is an important property of surfaces, which influences catalytic reactivity and charge injection at interfaces. It controls the availability of charge carriers in front of a surface. Modifying {phi} has been achieved by deposition of metals and molecules. For investigating {phi} at the atomic scale, scanning tunneling microscopy (STM) has become a widely used technique. STM measures an apparent barrier height {phi}{sub a}, which is commonly related to the sample work function {phi}{sub s} by: {phi}{sub a}=({phi}{sub s}+{phi}{sub t}- vertical stroke eV vertical stroke)/2, with {phi}{sub t} the work function of the tunneling tip, V the applied tunneling bias voltage, and -e the electron charge. Hence, the effect of the finite voltage in STM on {phi}{sub a} is assumed to be linear and the comparison of {phi}{sub a} measured at different surface sites is assumed to yield quantitative information about work function differences. Here, the dependence of {phi}{sub a} on the Pb film thickness and applied bias voltage V is investigated. {phi}{sub a} is found to vary significantly with V. This bias dependence leads to drastic changes and even inversion of contrast in spatial maps of {phi}{sub a}, which are related to the QWSs in the Pb

  10. Effect of 200 MeV Ag ion irradiation on pink noise and magneto-transport properties of La{sub 0.7}Ce{sub 0.3}MnO{sub 3} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Choudhary, R.J. [Nuclear Science Centre, Aruna Asaf Ali Marg, Post Box 10502, New Delhi 110 067 (India); Department of Physics, University of Pune, Pune 411 007 (India); Kumar, Ravi [Nuclear Science Centre, Aruna Asaf Ali Marg, Post Box 10502, New Delhi 110 067 (India)]. E-mail: ranade@nsc.ernet.in; Husain, Shahid [Department of Physics, Aligarh Muslim University, Aligarh 202 002 (India); Srivastava, J.P. [Department of Physics, Aligarh Muslim University, Aligarh 202 002 (India); Malik, S.K. [Tata Institute of Fundamental Research, Mumbai 400 005 (India); Patil, S.I. [Department of Physics, University of Pune, Pune 411 007 (India)

    2006-03-15

    Pulsed laser deposited thin films of electron doped La{sub 0.7}Ce{sub 0.3}MnO{sub 3} have been irradiated with 200 MeV Ag ions at different fluence values. The irradiation driven alteration on the pink noise (1/f noise), electrical and magneto-transport properties have been investigated. It is observed that the irradiation fluence adjusts the metal-insulator transition temperature, the magnetic field response to the resistance and the noise values. These parameters may assist in tuning these materials for applications. The film irradiated with the lower fluence value of 5 x 10{sup 1} ions/cm{sup 2} enhances the performance at room temperature. However, the film irradiated at higher fluence values manipulates these functionalities at lower temperature regime. The normalized noise values in the irradiated films are higher in ferromagnetic regime than in the paramagnetic regime. The observations have been explained on the basis of effects of the presence of swift heavy ion irradiation induced strain and defects.

  11. Magnetocaloric effect and temperature coefficient of resistance of La0.85Ag0.15MnO3 epitaxial thin films obtained by polymer-assisted deposition

    Directory of Open Access Journals (Sweden)

    Cobas Acosta R.

    2014-07-01

    Full Text Available We report the magnetocaloric effects and temperature coefficient of resistance (TCR of La0.85Ag0.15MnO3 epitaxial thin films grown on single-crystal substrates of LaAlO3 (001 and SrTiO3 (001 using the chemical solution approach of polymer-assisted deposition (PAD. The film thicknesses are in the range 30-35 nm. Magnetocaloric effects, with entropy changes of -2.14 J/kg.K, in the case of the LaAlO3 substrate and -2.72 J/kg.K for the SrTiO3 substrate, (corresponding to a magnetic field variation of 2T were obtained at room temperature. The refrigeration capacity at this field variation reached large values of 125 J/kg and 216 J/kg, indicating that these films prepared by PAD have the potential for microcooling applications. The temperature coefficient of resistance has been calculated from the resistivity measurements. A maximum TCR value of 3.01 % K-1 was obtained at 309 K, which shows that these films also have potential as uncooled thermometers for bolometric applications.

  12. Shielding superconductors with thin films

    CERN Document Server

    Posen, Sam; Catelani, Gianluigi; Liepe, Matthias U; Sethna, James P

    2015-01-01

    Determining the optimal arrangement of superconducting layers to withstand large amplitude AC magnetic fields is important for certain applications such as superconducting radiofrequency cavities. In this paper, we evaluate the shielding potential of the superconducting film/insulating film/superconductor (SIS') structure, a configuration that could provide benefits in screening large AC magnetic fields. After establishing that for high frequency magnetic fields, flux penetration must be avoided, the superheating field of the structure is calculated in the London limit both numerically and, for thin films, analytically. For intermediate film thicknesses and realistic material parameters we also solve numerically the Ginzburg-Landau equations. It is shown that a small enhancement of the superheating field is possible, on the order of a few percent, for the SIS' structure relative to a bulk superconductor of the film material, if the materials and thicknesses are chosen appropriately.

  13. Pulsed Laser Deposition and Reflection High-Energy Electron Diffraction studies of epitaxial long range order, nano- and microstructured Ag thin films grown on MgO, Al2 O3 , STO and Si

    Science.gov (United States)

    Velazquez, Daniel; Seibert, Rachel; Man, Hamdi; Spentzouris, Linda; Terry, Jeff

    2015-03-01

    Pulsed Laser Deposition is a state-of-the-art technique that allows for the fine tunability of the deposition rate, highly uniform and epitaxial sample growth, the ability to introduce partial pressures of gases into the experimental chamber for growth of complex materials without interfering with the energy source (laser). An auxiliary in situ technique for growth monitoring, Reflection High-Energy Electron Diffraction, is a powerful characterization tool for predictability of the surface physical structure both, qualitatively and quantitatively. RHEED patterns during and post deposition of Ag thin films on MgO, Al2O3, Si and STO substrtates are presented and their interpretations are compared with surface imaging techniques (SEM, STM) to evidence the usefulness of the technique.

  14. Surface plasmon resonance in nanostructured Ag incorporated ZnS films

    Energy Technology Data Exchange (ETDEWEB)

    Chalana, S. R.; Mahadevan Pillai, V. P., E-mail: vpmpillai9@gmail.com [Department of Optoelectronics, University of Kerala, Kariavattom, Thiruvananthapuram– 695581, Kerala (India); Ganesan, V. [UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore- 452017, Madhyapradesh (India)

    2015-10-15

    Silver incorporated zinc sulfide thin films are prepared by RF magnetron sputtering technique and the influence of silver incorporation on the structural, optical and luminescence properties is analyzed using techniques like grazing incidence X-Ray diffraction (GIXRD), atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), micro-Raman spectroscopy, UV-Vis spectroscopy and laser photoluminescence spectroscopy. XRD analysis presents hexagonal wurtzite structure for the films. A reduction of crystallinity of the films is observed due to Ag incorporation. The Raman spectral analysis confirms the reduction of crystallinity and increase of strain due to the Ag incorporation. AFM analysis reveals a rough surface morphology for the undoped film and Ag incorporation makes the films uniform, dense and smooth. A blue shift of band gap energy with increase in Ag incorporation is observed due to quantum confinement effect. An absorption band (450-650 nm region) due to surface plasmon resonance of the Ag clusters present in the ZnS matrix is observed for the samples with higher Ag incorporation. The complex dielectric constant, loss factor and distribution of volume and surface energy loss of the ZnS thin films are calculated. Laser photoluminescence measurements gives an intense bluish green emission from the ZnS films and a quenching of the PL emission is observed which can be due to the metal plasmonic absorption and non-radiative energy transfer due to Ag incorporation.

  15. Surface plasmon resonance in nanostructured Ag incorporated ZnS films

    Directory of Open Access Journals (Sweden)

    S. R. Chalana

    2015-10-01

    Full Text Available Silver incorporated zinc sulfide thin films are prepared by RF magnetron sputtering technique and the influence of silver incorporation on the structural, optical and luminescence properties is analyzed using techniques like grazing incidence X-Ray diffraction (GIXRD, atomic force microscopy (AFM, field emission scanning electron microscopy (FESEM, energy dispersive X-ray spectroscopy (EDS, micro-Raman spectroscopy, UV-Vis spectroscopy and laser photoluminescence spectroscopy. XRD analysis presents hexagonal wurtzite structure for the films. A reduction of crystallinity of the films is observed due to Ag incorporation. The Raman spectral analysis confirms the reduction of crystallinity and increase of strain due to the Ag incorporation. AFM analysis reveals a rough surface morphology for the undoped film and Ag incorporation makes the films uniform, dense and smooth. A blue shift of band gap energy with increase in Ag incorporation is observed due to quantum confinement effect. An absorption band (450-650 nm region due to surface plasmon resonance of the Ag clusters present in the ZnS matrix is observed for the samples with higher Ag incorporation. The complex dielectric constant, loss factor and distribution of volume and surface energy loss of the ZnS thin films are calculated. Laser photoluminescence measurements gives an intense bluish green emission from the ZnS films and a quenching of the PL emission is observed which can be due to the metal plasmonic absorption and non-radiative energy transfer due to Ag incorporation.

  16. Ferroelectric Thin Film Development

    Science.gov (United States)

    2003-12-10

    less. The film temper- ature is monitored by thermocouple sensors. Process gases pass through the chamber during the process. An advantage of RTP is the...semiconductor InSe ,” J. Appl. Phys., vol. 86, pp. 5687–5691, November 1999. 37. R. Mollers and R. Memming Ber. Bunsenges. Phys. Chem., vol. 76, 1972. 38. M

  17. Growth and Electronic Properties of Ag Nanoparticles on Reduced CeO2-x(111) Films

    Institute of Scientific and Technical Information of China (English)

    Dan-dan Kong; Yong-he Pan; Guo-dong Wang; Hai-bin Pan; Jun-fa Zhu

    2012-01-01

    Ag nanoparticles grown on reduced CeO2-x thin films have been studied by X-ray photoelectron spectroscopy and resonant photoelectron spectroscopy of the valence band to understand the effect of oxygen vacancies in the CeO2-x thin films on the growth and interfacial electronic properties of Ag.Ag grows as three-dimensional particles on the CeO2-x(111) surface at 300 K.Compared to the fully oxidized ceria substrate surface,Ag favors the growth of smaller particles with a larger particle density on the reduced ceria substrate surface,which can be attributed to the nucleation of Ag on oxygen vacancies.The binding energy of Ag3d increases when the Ag particle size decreases,which is mainly attributed to the final-state screening.The interfacial interaction between Ag and CeO2-x(111) is weak.The resonant enhancement of the 4f level of Ce3+ species in RPES indicates a partial Ce4+→Ce3+ reduction after Ag deposited on reduced ceria surface.The sintering temperature of Ag on CeO 1.85 (111) surface during annealing is a little higher than that of Ag on CeO2 (111) surface,indicating that Ag nanoparticles are more stable on the reduced ceria surface.

  18. PLD-grown thin film saturable absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Tellkamp, Friedjof

    2012-11-01

    The subject of this thesis is the preparation and characterization of thin films made of oxidic dielectrics which may find their application as saturable absorber in passively Q-switched lasers. The solely process applied for fabrication of the thin films was the pulsed laser deposition (PLD) which stands out against other processes by its flexibility considering the composition of the systems to be investigated. Within the scope of this thesis the applied saturable absorbers can be divided into two fundamentally different kinds of functional principles: On the one hand, saturable absorption can be achieved by ions embedded in a host medium. Most commonly applied bulk crystals are certain garnets like YAG (Y{sub 3}Al{sub 5}O{sub 12}) or the spinel forsterite (Mg{sub 2}SiO{sub 4}), in each case with chromium as dopant. Either of these media was investigated in terms of their behavior as PLD-grown saturable absorber. Moreover, experiments with Mg{sub 2}GeO{sub 4}, Ca{sub 2}GeO{sub 4}, Sc{sub 2}O{sub 3}, and further garnets like YSAG or GSGG took place. The absorption coefficients of the grown films of Cr{sup 4+}:YAG were determined by spectroscopic investigations to be one to two orders of magnitude higher compared to commercially available saturable absorbers. For the first time, passive Q-switching of a Nd:YAG laser at 1064 nm with Cr{sup 4+}:YAG thin films could be realized as well as with Cr:Sc{sub 2}O{sub 3} thin films. On the other hand, the desirable effect of saturable absorption can also be generated by quantum well structures. For this purpose, several layer system like YAG/LuAG, Cu{sub 2}O/MgO, and ZnO/corumdum were investigated. It turned out that layer systems with indium oxide (In{sub 2}O{sub 3}) did not only grew in an excellent way but also showed up a behavior regarding their photo luminescence which cannot be explained by classical considerations. The observed luminescence at roughly 3 eV (410 nm) was assumed to be of excitonic nature and its

  19. Low-temperature preparation of anatase thin films on tantalum.

    Science.gov (United States)

    Johnson, Scott E; Burgoon, Matthew W P; Wang, Qi; White, J M

    2006-07-18

    Titanium dioxide thin films were grown on oxidized Ta surfaces using a cyclic layer-by-layer wet chemistry method: successive-ionic-layer-adsorption-and-reaction (SILAR). Film thicknesses varied monotonically and approximately linearly with the number of cycles. As-grown (AG) films were amorphous and rougher (16.2 nm root-mean-square (rms)) than the Ta substrate (10.2 nm rms). After hydrothermal annealing (AN) at a remarkably low temperature of 393 K, the films exhibited anatase crystallites (10 nm dimensions) and reduced roughness (11.8 nm rms). The atomic composition of both AG and AN films was consistent with that of TiO2 containing no more than 4 atom % carbon. A small Si impurity (<1 atom %) was eliminated by using polypropylene beakers and sample holders in the SILAR steps.

  20. Thin-Film Metamaterials called Sculptured Thin Films

    CERN Document Server

    Lakhtakia, Akhlesh

    2010-01-01

    Morphology and performance are conjointed attributes of metamaterials, of which sculptured thin films (STFs) are examples. STFs are assemblies of nanowires that can be fabricated from many different materials, typically via physical vapor deposition onto rotating substrates. The curvilinear--nanowire morphology of STFs is determined by the substrate motions during fabrication. The optical properties, especially, can be tailored by varying the morphology of STFs. In many cases prototype devices have been fabricated for various optical, thermal, chemical, and biological applications.

  1. Antimicrobial activity of thin solid films of silver doped hydroxyapatite prepared by sol-gel method.

    Science.gov (United States)

    Iconaru, Simona Liliana; Chapon, Patrick; Le Coustumer, Philippe; Predoi, Daniela

    2014-01-01

    In this work, the preparation and characterization of silver doped hydroxyapatite thin films were reported and their antimicrobial activity was characterized. Silver doped hydroxyapatite (Ag:HAp) thin films coatings substrate was prepared on commercially pure Si disks by sol-gel method. The silver doped hydroxyapatite thin films were characterized by various techniques such as Scanning electron microscopy (SEM) with energy Dispersive X-ray attachment (X-EDS), Fourier transform infrared spectroscopy (FT-IR), and glow discharge optical emission spectroscopy (GDOES). These techniques have permitted the structural and chemical characterisation of the silver doped hydroxyapatite thin films. The antimicrobial effect of the Ag:HAp thin films on Escherichia coli and Staphylococcus aureus bacteria was then investigated. This is the first study on the antimicrobial effect of Ag:HAp thin films obtained by sol-gel method. The results of this study have shown that the Ag:HAp thin films with x(Ag) = 0.5 are effective against E. coli and S. aureus after 24 h.

  2. Antimicrobial Activity of Thin Solid Films of Silver Doped Hydroxyapatite Prepared by Sol-Gel Method

    Directory of Open Access Journals (Sweden)

    Simona Liliana Iconaru

    2014-01-01

    Full Text Available In this work, the preparation and characterization of silver doped hydroxyapatite thin films were reported and their antimicrobial activity was characterized. Silver doped hydroxyapatite (Ag:HAp thin films coatings substrate was prepared on commercially pure Si disks by sol-gel method. The silver doped hydroxyapatite thin films were characterized by various techniques such as Scanning electron microscopy (SEM with energy Dispersive X-ray attachment (X-EDS, Fourier transform infrared spectroscopy (FT-IR, and glow discharge optical emission spectroscopy (GDOES. These techniques have permitted the structural and chemical characterisation of the silver doped hydroxyapatite thin films. The antimicrobial effect of the Ag:HAp thin films on Escherichia coli and Staphylococcus aureus bacteria was then investigated. This is the first study on the antimicrobial effect of Ag:HAp thin films obtained by sol-gel method. The results of this study have shown that the Ag:HAp thin films with xAg=0.5 are effective against E. coli and S. aureus after 24 h.

  3. A novel P/Ag/Ag2O/Ag3PO4/TiO2 composite film for water purification and antibacterial application under solar light irradiation.

    Science.gov (United States)

    Zhu, Qi; Hu, Xiaohong; Stanislaus, Mishma S; Zhang, Nan; Xiao, Ruida; Liu, Na; Yang, Yingnan

    2017-01-15

    TiO2-based thin films have been intensively studied in recent years to develop efficient photocatalyst films to degrade refractory organics and inactivate bacteria for wastewater treatment. In the present work, P/Ag/Ag2O/Ag3PO4/TiO2 composite films on the inner-surface of glass tube were successfully prepared via sol-gel approach. P/Ag/Ag2O/Ag3PO4/TiO2 composite films with 3 coating layers, synthesized at 400°C for 2h, showed the optimal photocatalytic performance for rhodamine B (Rh B) degradation. The results indicated that degradation ratio of Rh B by P/Ag/Ag2O/Ag3PO4/TiO2 composite film reached 99.9% after 60min under simulated solar light, while just 67.9% of Rh B was degraded by pure TiO2 film. Moreover, repeatability experiments indicated that even after five recycling runs, the photodegradation ratio of Rh B over composite film maintained at 99.9%, demonstrating its high stability. Photocatalytic inactivation of E. coli with initial concentration of 10(7)CFU/mL also showed around 100% of sterilization ratio under simulated solar light irradiation in 5min by the composite film. The radical trapping experiments implied that the major active species of P/Ag/Ag2O/Ag3PO4/TiO2 composite films were photo-generated holes and O2(-) radicals. The proposed photocatalytic mechanism shows that the transfer of photo-induced electrons and holes may reduce the recombination efficiency of electron-hole pairs and potential photodecomposition of composite film, resulting in enhanced photocatalytic ability of P/Ag/Ag2O/Ag3PO4/TiO2 composite films.

  4. Selective inorganic thin films

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, M.L.F.; Pohl, P.I.; Brinker, C.J. [Sandia National Labs., Albuquerque, NM (United States)

    1997-04-01

    Separating light gases using membranes is a technology area for which there exists opportunities for significant energy savings. Examples of industrial needs for gas separation include hydrogen recovery, natural gas purification, and dehydration. A membrane capable of separating H{sub 2} from other gases at high temperatures could recover hydrogen from refinery waste streams, and facilitate catalytic dehydrogenation and the water gas shift (CO + H{sub 2}O {yields} H{sub 2} + CO{sub 2}) reaction. Natural gas purification requires separating CH{sub 4} from mixtures with CO{sub 2}, H{sub 2}S, H{sub 2}O, and higher alkanes. A dehydrating membrane would remove water vapor from gas streams in which water is a byproduct or a contaminant, such as refrigeration systems. Molecular sieve films offer the possibility of performing separations involving hydrogen, natural gas constituents, and water vapor at elevated temperatures with very high separation factors. It is in applications such as these that the authors expect inorganic molecular sieve membranes to compete most effectively with current gas separation technologies. Cryogenic separations are very energy intensive. Polymer membranes do not have the thermal stability appropriate for high temperature hydrogen recovery, and tend to swell in the presence of hydrocarbon natural gas constituents. The authors goal is to develop a family of microporous oxide films that offer permeability and selectivity exceeding those of polymer membranes, allowing gas membranes to compete with cryogenic and adsorption technologies for large-scale gas separation applications.

  5. Comparison of optical transients during the picosecond laser pulse-induced crystallization of GeSbTe and AgInSbTe phase-change thin films: Nucleation-driven versus growth-driven processes

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Guangfei [Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Li, Simian [State Key Laboratory of Optoelectronic Materials and Technology, Department of Physics, Sun Yat-Sen University, Guangzhou 510275 (China); Huang, Huan [Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Wang, Yang, E-mail: ywang@siom.ac.cn [Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Lai, Tianshu, E-mail: stslts@mail.sysu.edu.cn [State Key Laboratory of Optoelectronic Materials and Technology, Department of Physics, Sun Yat-Sen University, Guangzhou 510275 (China); Wu, Yiqun [Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2013-09-01

    Direct comparison of the real-time in-situ crystallization behavior of as-deposited amorphous Ge{sub 2}Sb{sub 2}Te{sub 5} (GeSbTe) and Ag{sub 8}In{sub 14}Sb{sub 55}Te{sub 23} (AgInSbTe) phase-change thin films driven by picosecond laser pulses was performed by a time-resolved optical pump-probe technique with nanosecond resolution. Different optical transients showed various crystallization processes because of the dissimilar nucleation- and growth-dominated mechanisms of the two materials. The effects of laser pulse fluence, thermal conductive structure, and successive pulse irradiation on their crystallization dynamics were also discussed. A schematic was then established to describe the different crystallization processes beginning from the as-deposited amorphous state. The results may provide further insight into the phase-change mechanism under extra-non-equilibrium conditions and aid the development of ultrafast phase-change memory materials.

  6. Thin films of soft matter

    CERN Document Server

    Kalliadasis, Serafim

    2007-01-01

    A detailed overview and comprehensive analysis of the main theoretical and experimental advances on free surface thin film and jet flows of soft matter is given. At the theoretical front the book outlines the basic equations and boundary conditions and the derivation of low-dimensional models for the evolution of the free surface. Such models include long-wave expansions and equations of the boundary layer type and are analyzed via linear stability analysis, weakly nonlinear theories and strongly nonlinear analysis including construction of stationary periodic and solitary wave and similarity solutions. At the experimental front a variety of very recent experimental developments is outlined and the link between theory and experiments is illustrated. Such experiments include spreading drops and bubbles, imbibitions, singularity formation at interfaces and experimental characterization of thin films using atomic force microscopy, ellipsometry and contact angle measurements and analysis of patterns using Minkows...

  7. Polycrystalline thin films : A review

    Energy Technology Data Exchange (ETDEWEB)

    Valvoda, V. [Charles Univ., Prague (Czech Republic). Faculty of Mathematics and Physics

    1996-09-01

    Polycrystalline thin films can be described in terms of grain morphology and in terms of their packing by the Thornton`s zone model as a function of temperature of deposition and as a function of energy of deposited atoms. Grain size and preferred grain orientation (texture) can be determined by X-ray diffraction (XRD) methods. A review of XRD analytical methods of texture analysis is given with main attention paid to simple empirical functions used for texture description and for structure analysis by joint texture refinement. To illustrate the methods of detailed structure analysis of thin polycrystalline films, examples of multilayers are used with the aim to show experiments and data evaluation to determine layer thickness, periodicity, interface roughness, lattice spacing, strain and the size of diffraction coherent volumes. The methods of low angle and high angle XRD are described and discussed with respect to their complementary information content.

  8. Thermal durability of AZO/Ag(Al)/AZO transparent conductive films

    Science.gov (United States)

    Sugimoto, Yukiko; Igarashi, Kanae; Shirasaki, Shinya; Kikuchi, Akihiko

    2016-04-01

    Effects of Al doping on surface morphology, sheet resistance, optical transmission spectra, and thermal durability of a thin Ag layer and AZO/Ag/AZO dielectric/metal/dielectric (DMD) transparent conductive films (TCFs) were investigated. The 1.7 at. % Al doping suppressed the initial island growth of a thin Ag layer and the plasmon resonant absorption dip in the optical transmission spectra. The threshold thickness of percolation conductivity was reduced from 9-10 (pure Al layer) to 5-6 nm (1.7 at. % Al-doped Ag layer). Al doping in the Ag layer improved the thermal durability of AZO/Ag/AZO-DMD TCFs. The threshold temperature for Ag void formation increased from 400 °C (DMD with pure Ag layer) to 600 °C (DMD with a 10.5 at. % Al-doped Ag layer). The optimum annealing temperature increased from 300 °C (DMD with a pure Ag layer) to 500 °C (DMD with a 10.5 at. % Al-doped Ag layer). Maximum figures of merit (FOM) were 0.5 × 10-2 and 1.1 × 10-2 Ω-1 for the DMD with a pure Ag layer and that with a 10.5 at. % Al-doped Ag layer, respectively.

  9. Photoconductivity of thin organic films

    Science.gov (United States)

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

    2010-04-01

    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 ( C60), 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 C60 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 × 10 3 Ω m and 3 × 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 × 10 8 Ω m in dark to 3.1 × 10 6 Ω m under the light.

  10. Photoconductivity of thin organic films

    Energy Technology Data Exchange (ETDEWEB)

    Tkachenko, Nikolai V. [Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FIN-33101 Tampere (Finland); Chukharev, Vladimir, E-mail: Vladimir.Chukharev@tut.fi [Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FIN-33101 Tampere (Finland); Kaplas, Petra; Tolkki, Antti; Efimov, Alexander [Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FIN-33101 Tampere (Finland); Haring, Kimmo; Viheriaelae, Jukka; Niemi, Tapio [Optoelectronics Research Centre, Tampere University of Technology, P.O. Box 692, FIN-33101 Tampere (Finland); Lemmetyinen, Helge [Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, FIN-33101 Tampere (Finland)

    2010-04-01

    Thin organic films were deposited on silicon oxide surfaces with golden interdigitated electrodes (interelectrode gap was 2 {mu}m), 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{sub 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{sub 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{sup 3} {Omega} m and 3 x 10{sup 4} {Omega} 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{sup 8} {Omega} m in dark to 3.1 x 10{sup 6} {Omega} m under the light.

  11. Flexible thin film magnetoimpedance sensors

    Energy Technology Data Exchange (ETDEWEB)

    Kurlyandskaya, G.V., E-mail: galina@we.lc.ehu.es [Universidad del País Vasco, UPV/EHU, Departamento de Electricidad y Electrónica, P.O. Box 644, Bilbao 48080 (Spain); Ural Federal University, Laboratory of Magnetic sensoric, Lenin Ave. 51, 620083 Ekaterinburg (Russian Federation); Fernández, E. [BCMaterials UPV-EHU, Vizcaya Science and Technology Park, 48160 Derio (Spain); Svalov, A. [Universidad del País Vasco, UPV/EHU, Departamento de Electricidad y Electrónica, P.O. Box 644, Bilbao 48080 (Spain); Ural Federal University, Laboratory of Magnetic sensoric, Lenin Ave. 51, 620083 Ekaterinburg (Russian Federation); Burgoa Beitia, A. [Universidad del País Vasco, UPV/EHU, Departamento de Electricidad y Electrónica, P.O. Box 644, Bilbao 48080 (Spain); García-Arribas, A. [Universidad del País Vasco, UPV/EHU, Departamento de Electricidad y Electrónica, P.O. Box 644, Bilbao 48080 (Spain); BCMaterials UPV-EHU, Vizcaya Science and Technology Park, 48160 Derio (Spain); Larrañaga, A. [SGIker, Servicios Generales de Investigación, Universidad del País Vasco (UPV/EHU), 48080 Bilbao (Spain)

    2016-10-01

    Magnetically soft thin film deposited onto polymer substrates is an attractive option for flexible electronics including magnetoimpedance (MI) applications. MI FeNi/Ti based thin film sensitive elements were designed and prepared using the sputtering technique by deposition onto rigid and flexible substrates at different deposition rates. Their structure, magnetic properties and MI were comparatively analyzed. The main structural features were sufficiently accurately reproduced in the case of deposition onto cyclo olefine polymer substrates compared to glass substrates for the same conditions. Although for the best condition (28 nm/min rate) of the deposition onto polymer a significant reduction of the MI field sensitivity was found satisfactory for sensor applications sensitivity: 45%/Oe was obtained for a frequency of 60 MHz. - Highlights: • [FeNi/Ti]{sub 3}/Cu/[FeNi/Ti]{sub 3} films were prepared by sputtering at different deposition rates. • Polymer substrates insure sufficiently accurate reproducibility of the film structure. • High deposition rate of 28 nm/min insures the highest values of the magnetoimpedance sensitivity. • Deposition onto polymer results in the satisfactory magnetoimpedance sensitivity of 45%/Oe.

  12. Optical properties and structures of silver thin films deposited by magnetron sputtering with different thicknesses

    Institute of Scientific and Technical Information of China (English)

    Xilian Sun; Ruijin Hong; Haihong Hou; Zhengxiu Fan; Jianda Shao

    2006-01-01

    A series of thin Ag films with different thicknesses grown under identical conditions are analyzed by means of spectrophotometer. From these measurements the values of refractive index and extinction coefficient are calculated. The films are deposited onto BK7 glass substrates by direct current (DC) magnetron sputtering. It is found that the optical properties of the Ag films can be affected by films thickness.Below critical thickness of 17 nm, which is the thickness at which Ag films form continuous films, the optical properties and constants vary significantly with thickness increasing and then tend to a stable value up to about 40 nm. At the same time, X-ray diffraction measurement is carried out to examine the microstructure evolution of Ag films as a function of films thickness. The relation between optical properties and microstructure is discussed.

  13. Selective epitaxial growth for YBCO thin films

    NARCIS (Netherlands)

    Damen, C.A.J.; Smilde, H.-J.H.; Blank, D.H.A.; Rogalla, H.

    1998-01-01

    A novel selective epitaxial growth (SEG) technique for (YBCO) thin films is presented. The method involves the deposition of a thin (about 10 nm) metal layer, in the desired pattern, on a substrate before the deposition of the superconducting thin film. During growth the metal reacts with the YBCO,

  14. Morphology and oxygen incorporation effect on antimicrobial activity of silver thin films

    Energy Technology Data Exchange (ETDEWEB)

    Rebelo, Rita, E-mail: ritarebelo@det.uminho.pt [2C2T, University of Minho, Campus de Azurém, 4800-058 Guimarães (Portugal); GRF-CFUM, University of Minho, Campus de Azurém, 4800-058 Guimarães (Portugal); CEB, Center for Biological Engineering, LIBRO—Laboratório de Biofilmes Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-335 Braga (Portugal); Manninen, N.K. [GRF-CFUM, University of Minho, Campus de Azurém, 4800-058 Guimarães (Portugal); SEG-CEMUC, University of Coimbra, 3030-788 Coimbra (Portugal); Fialho, Luísa [GRF-CFUM, University of Minho, Campus de Azurém, 4800-058 Guimarães (Portugal); Henriques, Mariana [CEB, Center for Biological Engineering, LIBRO—Laboratório de Biofilmes Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-335 Braga (Portugal); Carvalho, Sandra [GRF-CFUM, University of Minho, Campus de Azurém, 4800-058 Guimarães (Portugal); SEG-CEMUC, University of Coimbra, 3030-788 Coimbra (Portugal)

    2016-05-15

    Highlights: • Ag and Ag{sub x}O thin films were deposited by non-reactive and reactive pulsed DC magnetron sputtering. • Coatings were characterized chemically, physically and structurally. • In order to verify the antibacterial behavior of the coatings, halo inhibition zone tests were realized for Staphylococcus epidermidis and Staphylococcus aureus. • Ag{sub x}O coating presented antibacterial behavior. - Abstract: Ag and Ag{sub x}O thin films were deposited by non-reactive and reactive pulsed DC magnetron sputtering, respectively, with the final propose of functionalizing the SS316L substrate with antibacterial properties. The coatings were characterized chemically, physically and structurally. The coatings nanostructure was assessed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), while the coatings morphology was determined by scanning electron microscopy (SEM). The XRD and XPS analyses suggested that Ag thin film is composed by metallic Ag, which crystallizes in fcc-Ag phase, while the Ag{sub x}O thin film showed both metallic Ag and Ag−O bonds, which crystalize in fcc-Ag and silver oxide phases. The SEM results revealed that Ag thin film formed a continuous layer, while Ag{sub x}O layer was composed of islands with hundreds of nanometers surrounded by small nanoparticles with tens of nanometers. The surface wettability and surface tension parameters were determined by contact angle measurements, being found that Ag and Ag{sub x}O surfaces showed very similar behavior, with all the surfaces showing a hydrophobic character. In order to verify the antibacterial behavior of the coatings, halo inhibition zone tests were realized for Staphylococcus epidermidis and Staphylococcus aureus. Ag coatings did not show antibacterial behavior, contrarily to Ag{sub x}O coating, which presented antibacterial properties against the studied bacteria. The presence of silver oxide phase along with the development of different morphology was

  15. Biaxially textured Ag films by grazing ion beam assisted deposition

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, Daniel F., E-mail: foerster@ph2.uni-koeln.d [II. Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln (Germany); Bleikamp, Sebastian; Michely, Thomas [II. Physikalisches Institut, Universitaet zu Koeln, 50937 Koeln (Germany)

    2010-11-01

    The effect of grazing incidence 4 keV Ar{sup +} ion irradiation on the early stage of Ag thin film growth on amorphous Si was investigated. The double effect of axial and surface channeling resulted in grains oriented along the <110> axis in-plane, while the (111) out-of-plane texture was maintained. A slight average tilt of the (111) out-of-plane texture axis towards the ion beam direction is proposed to result from the difference between terrace and step edge sputtering yield. The observed tilt is consistent with a minimum erosion orientation of the surface profile.

  16. Evaluation of the Antimicrobial Activity of Different Antibiotics Enhanced with Silver-Doped Hydroxyapatite Thin Films

    Directory of Open Access Journals (Sweden)

    Daniela Predoi

    2016-09-01

    Full Text Available The inhibitory and antimicrobial effects of silver particles have been known since ancient times. In the last few years, a major health problem has arisen due to pathogenic bacteria resistance to antimicrobial agents. The antibacterial activities of new materials including hydroxyapatite (HAp, silver-doped hydroxyapatite (Ag:HAp and various types of antibiotics such as tetracycline (T-HAp and T-Ag:HAp or ciprofloxacin (C-HAp and C-Ag:HAp have not been studied so far. In this study we reported, for the first time, the preparation and characterization of various thin films based on hydroxyapatite and silver-doped hydroxyapatite combined with tetracycline or ciprofloxacin. The structural and chemical characterization of hydroxyapatite and silver-doped hydroxyapatite thin films has been evaluated by X-ray diffraction (XRD and Fourier transform infrared spectroscopy (FTIR. The morphological studies of the HAp, Ag:HAp, T-HAp, T-Ag:HAp, C-HAp and C-Ag:HAp thin solid films were performed using scanning electron microscopy (SEM. In order to study the chemical composition of the coatings, energy dispersive X-ray analysis (EDX and glow discharge optical emission spectroscopy (GDOES measurements have been used, obtaining information on the distribution of the elements throughout the film. These studies have confirmed the purity of the prepared hydroxyapatite and silver-doped hydroxyapatite thin films obtained from composite targets containing Ca10−xAgx(PO46(OH2 with xAg = 0 (HAp and xAg = 0.2 (Ag:HAp. On the other hand, the major aim of this study was the evaluation of the antibacterial activities of ciprofloxacin and tetracycline in the presence of HAp and Ag:HAp thin layers against Staphylococcus aureus and Escherichia coli strains. The antibacterial activities of ciprofloxacin and tetracycline against Staphylococcus aureus and Escherichia coli test strains increased in the presence of HAp and Ag:HAp thin layers.

  17. High-Jc YBa2Cu3O7-x-Ag superconducting thin films synthesized through a fluorine-free MOD method

    DEFF Research Database (Denmark)

    Tang, Xiao; Yue, Zhao; Wu, W.

    2015-01-01

    and ammonia, AgNO3 was initially mixed with YBCO carboxylate precursors dissolved in methanol. High-temperature in situ XRD measurements on the YBCO-Ag powders revealed that silver addition lowers the incongruent melting temperature of YBCO to 760°C and resulted in a smooth surface morphology of the YBCO...

  18. Microstructure and optical properties of nano Ag-ITO films

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Nano Ag-ITO films with Ag volume fraction of 0.3%-1.0% were prepared by radio-frequency magnetron co-sputtering and analyzed by X-ray diffraction,scanning electron microscopy and ultraviolet-visible spectroscopy.Microstructure analysis shows that the films are composed of polycrystalline ITO matrix embedded with Ag nanoparticles with a mean size of 60-100 nm.Transmissivity spectra of Ag-ITO films indicate that the visible light transmissivity of the films decreases with increasing the Ag fraction.The transmissivity of the annealed films is higher than that of the as-deposited films.The volume 0.3% Ag-ITO films have the highest light reflectance.The annealed films exhibit lower light absorptance than as-deposited films.A surface plasmon resonance(SPR) peak of volume 0.3% Ag-ITO films is located around 510 nm.Compared with the annealed ITO film,the annealed volume 0.3% Ag-ITO film shows 10% higher reflectivity,while its transmittance is almost the same as that of the annealed ITO film,indicating its potential application in new-type transflective displays.

  19. 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.

  20. Alloy formation during the electrochemical growth of a Ag-Cd ultrathin film on Au(1 1 1)

    Energy Technology Data Exchange (ETDEWEB)

    Barrio, M.C. del; Garcia, S.G. [Instituto de Ingenieria Electroquimica y Corrosion (INIEC), Departamento de Ingenieria Quimica, Universidad Nacional del Sur, Avda. Alem 1253, 8000 Bahia Blanca (Argentina); Salinas, D.R., E-mail: dsalinas@uns.edu.a [Instituto de Ingenieria Electroquimica y Corrosion (INIEC), Departamento de Ingenieria Quimica, Universidad Nacional del Sur, Avda. Alem 1253, 8000 Bahia Blanca (Argentina)

    2009-12-30

    The electrodeposition of a Ag/Cd ultrathin film on a Au(1 1 1) surface and the formation of a surface alloy during this process have been studied using classical electrochemical techniques and in situ Scanning Tunneling Microscopy (STM). The films were obtained from separate electrolytes containing Ag{sup +} or Cd{sup 2+} ions and from a multicomponent solution containing both ions. First, the polarization conditions were adjusted in order to form a Ag film by overpotential deposition. Afterwards, a Cd monolayer was formed onto this Au(1 1 1)/Ag modified surface by underpotential deposition. The voltammetric behavior of the Cd UPD and the in situ STM images indicated that the ultrathin Ag films were uniformly deposited and epitaxially oriented with respect to the Au(1 1 1) surface. Long time polarization experiments showed that a significant Ag-Cd surface alloying accompanied the formation of the Cd monolayer on the Au(1 1 1)/Ag modified surface, independent of the Ag film thickness. In the case of an extremely thin Ag layer (1 Ag ML) the STM images and long time polarization experiments revealed a solid state diffusion process of Cd, Ag, and Au atoms which can be responsible for the formation of different Ag-Cd or Au-Ag-Cd alloy phases.

  1. Thin film fuel cell electrodes.

    Science.gov (United States)

    Asher, W. J.; Batzold, J. S.

    1972-01-01

    Earlier work shows that fuel cell electrodes prepared by sputtering thin films of platinum on porous vycor substrates avoid diffusion limitations even at high current densities. The presented study shows that the specific activity of sputtered platinum is not unusually high. Performance limitations are found to be controlled by physical processes, even at low loadings. Catalyst activity is strongly influenced by platinum sputtering parameters, which seemingly change the surface area of the catalyst layer. The use of porous nickel as a substrate shows that pore size of the substrate is an important parameter. It is noted that electrode performance increases with increasing loading for catalyst layers up to two microns thick, thus showing the physical properties of the sputtered layer to be different from platinum foil. Electrode performance is also sensitive to changing differential pressure across the electrode. The application of sputtered catalyst layers to fuel cell matrices for the purpose of obtaining thin total cells appears feasible.

  2. Co-doping effects of Gd and Ag on YBCO films derived by metalorganic deposition

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Meijuan; Liu, Zhiyong; Bai, Chuanyi; Guo, Yanqun; Lu, Yuming; Fan, Feng; Cai, Chuanbing, E-mail: cbcai@t.shu.edu.cn

    2015-12-15

    Highlights: • MOD was employed to fabricate (YGd)BaCuO films together with Ag addition for the first time. • Better connectivity of grains was obtained by Ag addition. • Pyrolysis rate and surface morphology were able to be improved by Ag addition. • Gd substitution and relevant ion defects are emerged in the studied (YGd)BaCuO films. • Better c-axis orientation, superior surface microstructure and improved superconducting performance are obtained by co-doping of Gd and Ag. - Abstract: Y{sub 1–x}Gd{sub x}Ba{sub 2}Cu{sub 3}O{sub 7–δ}-Ag (x = 0, 0.25, 0.5, 0.75, 1) thin films were prepared on oxide buffered Hastelloy substrates by low fluorine metalorganic depostion (MOD) process. The effects of co-doping of Ag and Gd on the microstructures and superconducting properties of YBCO thin films are investigated with respect to improvement on texture and superconducting performance in case of optimized doping content. It is found that optimum addition of Ag and Gd may lead to better c-axis orientation, superior surface microstructure and finally give rise to much improvement of superconducting performance.

  3. A facile strategy to synthesize bimetallic Au/Ag nanocomposite film by layer-by-layer assembly technique

    Science.gov (United States)

    Zhang, Li; Wang, Cong; Zhang, Yi

    2012-05-01

    A facile strategy has been developed for the preparation of bimetallic gold-silver (Au-Ag) nanocomposite films by alternating absorption of poly-(ethyleneimine)-silver ions and Au onto substrates and subsequent reduction of the silver ions. The composition, micro-structure and properties of the {PEI-Ag/Au}n nanocomposite films were characterized by ultraviolet visible spectroscopy (UV-vis), transmisson electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), surface enhanced Raman scattering (SERS) and cyclic voltammetry (CV). The UV-vis characteristic absorbances of {PEI-Ag/Au}n nanocomposite thin film increase almost linear with the number of bilayers, which indicates a process of uniform assembling. Appearance of a double plasmon bands in the visible region and the lack of apparent core-shell structures in the TEM images confirm the formation of bimetallic Au-Ag nanoparticles. The result of XPS also demonstrates the existence of Ag and Au nanoparticles in the nanocomposite films. TEM and FESEM images show that these Ag and Au nanoparticles in the films possess sphere structure with the size of 20-25 nm. The resulting {PEI-Ag/Au}n films inherit the properties from both the metal Ag and Au, which exhibits a unique performance in SERS and electrocatalytic activities to the oxidation of dopamine. As a result, the {PEI-Ag/Au}n films are more attractive compared to {PEI-Ag/PSS}n and {PEI/Au}n films.

  4. 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...

  5. Thickness-dependent spontaneous dewetting morphology of ultrathin Ag films.

    Science.gov (United States)

    Krishna, H; Sachan, R; Strader, J; Favazza, C; Khenner, M; Kalyanaraman, R

    2010-04-16

    We show here that the morphological pathway of spontaneous dewetting of ultrathin Ag films on SiO2 under nanosecond laser melting is dependent on film thickness. For films with thickness h of 2 nm intermolecular forces, we have estimated the morphological transition thickness for the intermolecular forces for Ag on SiO2. The theory predictions agree well with observations for Ag. These results show that it is possible to form a variety of complex Ag nanomorphologies in a consistent manner, which could be useful in optical applications of Ag surfaces, such as in surface enhanced Raman sensing.

  6. Ellipsometric Studies on Silver Telluride Thin Films

    Directory of Open Access Journals (Sweden)

    M. Pandiaraman

    2011-01-01

    Full Text Available Silver telluride thin films of thickness between 45 nm and 145 nm were thermally evaporated on well cleaned glass substrates at high vacuum better than 10 – 5 mbar. Silver telluride thin films are polycrystalline with monoclinic structure was confirmed by X-ray diffractogram studies. AFM and SEM images of these films are also recorded. The phase ratio and amplitude ratio of these films were recorded in the wavelength range between 300 nm and 700 nm using spectroscopic ellipsometry and analysed to determine its optical band gap, refractive index, extinction coefficient, and dielectric functions. High absorption coefficient determined from the analysis of recorded spectra indicates the presence of direct band transition. The optical band gap of silver telluride thin films is thickness dependent and proportional to square of reciprocal of thickness. The dependence of optical band gap of silver telluride thin films on film thickness has been explained through quantum size effect.

  7. Electrostatic thin film chemical and biological sensor

    Science.gov (United States)

    Prelas, Mark A.; Ghosh, Tushar K.; Tompson, Jr., Robert V.; Viswanath, Dabir; Loyalka, Sudarshan K.

    2010-01-19

    A chemical and biological agent sensor includes an electrostatic thin film supported by a substrate. The film includes an electrostatic charged surface to attract predetermined biological and chemical agents of interest. A charge collector associated with said electrostatic thin film collects charge associated with surface defects in the electrostatic film induced by the predetermined biological and chemical agents of interest. A preferred sensing system includes a charge based deep level transient spectroscopy system to read out charges from the film and match responses to data sets regarding the agents of interest. A method for sensing biological and chemical agents includes providing a thin sensing film having a predetermined electrostatic charge. The film is exposed to an environment suspected of containing the biological and chemical agents. Quantum surface effects on the film are measured. Biological and/or chemical agents can be detected, identified and quantified based on the measured quantum surface effects.

  8. Effects of Ru and Ag cap layers on microstructure and magnetic properties of FePt ultrathin films.

    Science.gov (United States)

    Liu, Mingfeng; Jin, Tianli; Hao, Liang; Cao, Jiangwei; Wang, Ying; Wu, Dongping; Bai, Jianmin; Wei, Fulin

    2015-01-01

    The effects of Ru and Ag cap layers on the microstructure and magnetic properties of the FePt ultrathin films have been investigated. The results indicate that i) The Ag cap layer segregates from the FePt/Ag bilayer, lowers the FePt ordering temperature, promotes the FePt thin films to form island structure, and enhances the coercivity; ii) The Ru cap layer increases the FePt ordering temperature, helps to maintain smooth continuous structure film, and restrains the FePt (001) orientation and perpendicular magnetic anisotropy (PMA). The effects become more pronounced for the 3-nm-thick FePt thin films. The effects can be mainly attributed to the different melting point and thermal expansion stress between the cap layer and FePt thin films.

  9. Effects of Ru and Ag cap layers on microstructure and magnetic properties of FePt ultrathin films

    Science.gov (United States)

    Liu, Mingfeng; Jin, Tianli; Hao, Liang; Cao, Jiangwei; Wang, Ying; Wu, Dongping; Bai, Jianmin; Wei, Fulin

    2015-04-01

    The effects of Ru and Ag cap layers on the microstructure and magnetic properties of the FePt ultrathin films have been investigated. The results indicate that i) The Ag cap layer segregates from the FePt/Ag bilayer, lowers the FePt ordering temperature, promotes the FePt thin films to form island structure, and enhances the coercivity; ii) The Ru cap layer increases the FePt ordering temperature, helps to maintain smooth continuous structure film, and restrains the FePt (001) orientation and perpendicular magnetic anisotropy (PMA). The effects become more pronounced for the 3-nm-thick FePt thin films. The effects can be mainly attributed to the different melting point and thermal expansion stress between the cap layer and FePt thin films.

  10. 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...

  11. Epitaxial Cu(001) films grown on a Cr/Ag/Fe/GaAs(001) buffer system

    Energy Technology Data Exchange (ETDEWEB)

    Gottlob, Daniel M., E-mail: d.gottlob@fz-juelich.de [Peter Grünberg Institut, Electronic Properties (PGI-6), Forschungszentrum Jülich, 52425 Jülich (Germany); Fakultät für Physik and Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen, 47048 Duisburg (Germany); Jansen, Thomas [Peter Grünberg Institut, Electronic Properties (PGI-6), Forschungszentrum Jülich, 52425 Jülich (Germany); Jülich-Aachen Research Alliance, Fundamentals for Future Information Technology (JARA-FIT), Forschungszentrum Jülich, 52425 Jülich (Germany); Hoppe, Michael [Peter Grünberg Institut, Electronic Properties (PGI-6), Forschungszentrum Jülich, 52425 Jülich (Germany); Bürgler, Daniel E. [Peter Grünberg Institut, Electronic Properties (PGI-6), Forschungszentrum Jülich, 52425 Jülich (Germany); Jülich-Aachen Research Alliance, Fundamentals for Future Information Technology (JARA-FIT), Forschungszentrum Jülich, 52425 Jülich (Germany); and others

    2014-07-01

    We present a procedure to prepare single-crystalline, high-purity Cu(001) films (templates) suitable as substrates for subsequent epitaxial thin-film growth. The template films were grown in a dedicated molecular-beam epitaxy system on a Cr/Ag/Fe/GaAs(001) buffer layer system. Low-energy electron diffraction and X-ray diffraction were applied to determine the surface orientation and the epitaxial relationship between all layers of the stack. Post-annealing at moderate temperatures enhances the quality of the film as shown by low-energy electron diffraction and atomic force microscopy. X-ray photoemission and Auger electron spectroscopy confirm that no atoms of the buffer layers diffuse into the Cu film during the initial preparation and the post-annealing treatment. The completed Cu(001) template system can be exposed to air and afterwards refurbished by Ar{sup +}-ion bombardment and annealing, enabling the transfer between vacuum systems. The procedure provides suitable conductive thin film templates for studies of epitaxial thin films, e.g. on the magnetic and magnetotransport properties of Co and Ni based films and multilayers. - Highlights: • Preparation of epitaxial Cu(001) template films on an insulating substrate • Characterization of template structure, orientation, cleanness, and roughness • Template films can be exposed to air and refurbished in different vacuum system. • Template films are suitable for further thin film growth at up to 570 K.

  12. A monolithic thin film electrochromic window

    Energy Technology Data Exchange (ETDEWEB)

    Goldner, R.B.; Arntz, F.O.; Berera, G.; Haas, T.E.; Wong, K.K. (Tufts Univ., Medford, MA (United States). Electro-Optics Technology Center); Wei, G. (Mobil Solar Energy Corp., Billerica, MA (United States)); Yu, P.C. (PPG Industries, Inc., Monroeville, PA (United States))

    1991-01-01

    Three closely related thin film solid state ionic devices that are potentially important for applications are: electrochromic smart windows, high energy density thin film rechargeable batteries, and thin film electrochemical sensors. Each usually has at least on mixed ion/electron conductor, an electron-blocking ion conductor, and an ion-blocking electron conductor, and many of the technical issues associated with thin film solid state ionics are common to all three devices. Since the electrochromic window has the added technical requirement of electrically-controlled optical modulation, (over the solar spectrum), and since research at the authors' institution has focused primarily on the window structure, this paper will address the electrochromic window, and particularly a monolithic variable reflectivity electrochromic window, as an illustrative example of some of the challenges and opportunities that are confronting the thin film solid state ionics community. 33 refs.

  13. A monolithic thin film electrochromic window

    Energy Technology Data Exchange (ETDEWEB)

    Goldner, R.B.; Arntz, F.O.; Berera, G.; Haas, T.E.; Wong, K.K. [Tufts Univ., Medford, MA (United States). Electro-Optics Technology Center; Wei, G. [Mobil Solar Energy Corp., Billerica, MA (United States); Yu, P.C. [PPG Industries, Inc., Monroeville, PA (United States)

    1991-12-31

    Three closely related thin film solid state ionic devices that are potentially important for applications are: electrochromic smart windows, high energy density thin film rechargeable batteries, and thin film electrochemical sensors. Each usually has at least on mixed ion/electron conductor, an electron-blocking ion conductor, and an ion-blocking electron conductor, and many of the technical issues associated with thin film solid state ionics are common to all three devices. Since the electrochromic window has the added technical requirement of electrically-controlled optical modulation, (over the solar spectrum), and since research at the authors` institution has focused primarily on the window structure, this paper will address the electrochromic window, and particularly a monolithic variable reflectivity electrochromic window, as an illustrative example of some of the challenges and opportunities that are confronting the thin film solid state ionics community. 33 refs.

  14. Magnetostrictive thin films for microwave spintronics.

    Science.gov (United States)

    Parkes, D E; Shelford, L R; Wadley, P; Holý, V; Wang, M; Hindmarch, A T; van der Laan, G; Campion, R P; Edmonds, K W; Cavill, S A; Rushforth, A W

    2013-01-01

    Multiferroic composite materials, consisting of coupled ferromagnetic and piezoelectric phases, are of great importance in the drive towards creating faster, smaller and more energy efficient devices for information and communications technologies. Such devices require thin ferromagnetic films with large magnetostriction and narrow microwave resonance linewidths. Both properties are often degraded, compared to bulk materials, due to structural imperfections and interface effects in the thin films. We report the development of epitaxial thin films of Galfenol (Fe81Ga19) with magnetostriction as large as the best reported values for bulk material. This allows the magnetic anisotropy and microwave resonant frequency to be tuned by voltage-induced strain, with a larger magnetoelectric response and a narrower linewidth than any previously reported Galfenol thin films. The combination of these properties make epitaxial thin films excellent candidates for developing tunable devices for magnetic information storage, processing and microwave communications.

  15. Nanostructured thin films and coatings functional properties

    CERN Document Server

    Zhang, Sam

    2010-01-01

    The second volume in ""The Handbook of Nanostructured Thin Films and Coatings"" set, this book focuses on functional properties, including optical, electronic, and electrical properties, as well as related devices and applications. It explores the large-scale fabrication of functional thin films with nanoarchitecture via chemical routes, the fabrication and characterization of SiC nanostructured/nanocomposite films, and low-dimensional nanocomposite fabrication and applications. The book also presents the properties of sol-gel-derived nanostructured thin films as well as silicon nanocrystals e

  16. Carbon nanotube based transparent conductive thin films.

    Science.gov (United States)

    Yu, X; Rajamani, R; Stelson, K A; Cui, T

    2006-07-01

    Carbon nanotube (CNT) based optically transparent and electrically conductive thin films are fabricated on plastic substrates in this study. Single-walled carbon nanotubes (SWNTs) are chemically treated with a mixture of concentrated sulfuric acid and nitric acid before being dispersed in aqueous surfactant-contained solutions. SWNT thin films are prepared from the stable SWNT solutions using wet coating techniques. The 100 nm thick SWNT thin film exhibits a surface resistivity of 6 kohms/square nanometer with an average transmittance of 88% on the visible light range, which is three times better than the films prepared from the high purity as-received SWNTs.

  17. Quantum-well-driven magnetism in thin films

    DEFF Research Database (Denmark)

    Mirbt, S.; Johansson, B.; Skriver, Hans Lomholt

    1996-01-01

    We have performed local spin-density calculations for an fee (100) Ag substrate covered by 1 to 16 monolayers (ML) of Pd. We find that thin films of Pd are magnetic with a moment of the order of 0.3 mu(B) except for films of 1-2 ML and 5-7 ML where magnetism is completely suppressed. We present...... a physically transparent explanation of this behavior in terms of the Stoner picture and magnetic quantum-well states....

  18. PREPARATION AND CHARACTERIZATION OF POLY-CRYSTALLINE SILICON THIN FILM

    Institute of Scientific and Technical Information of China (English)

    Y.F. Hu; H. Shen; Z.Y. Liu; L.S. Wen

    2003-01-01

    Poly-crystalline silicon thin film has big potential of reducing the cost of solar cells.In this paper the preparation of thin film is introduced, and then the morphology of poly-crystalline thin film is discussed. On the film we developed poly-crystalline silicon thin film solar cells with efficiency up to 6. 05% without anti-reflection coating.

  19. Thermal Expansion Coefficients of Thin Crystal Films

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The formulas for atomic displacements and Hamiltonian of a thin crystal film in phonon occupation number representation are obtained with the aid of Green's function theory. On the basis of these results, the formulas for thermal expansion coefficients of the thin crystal film are derived with the perturbation theory, and the numerical calculations are carried out. The results show that the thinner films have larger thermal expansion coefficients.

  20. BDS thin film damage competition

    Energy Technology Data Exchange (ETDEWEB)

    Stolz, C J; Thomas, M D; Griffin, A J

    2008-10-24

    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.

  1. Thin film bioreactors in space

    Science.gov (United States)

    Hughes-Fulford, M.; Scheld, H. W.

    Studies from the Skylab, SL-3 and D-1 missions have demonstrated that biological organisms grown in microgravity have changes in basic cellular functions such as DNA, mRNA and protein synthesis, cytoskeleton synthesis, glucose utilization and cellular differentiation. Since microgravity could affect prokaryotic and eukaryotic cells at a subcellular and molecular level, space offers us an opportunity to learn more about basic biological systems with one important variable removed. The thin film bioreactor will facilitate the handling of fluids in microgravity, under constant temperature and will allow multiple samples of cells to be grown with variable conditions. Studies on cell cultures grown in microgravity would enable us to identify and quantify changes in basic biological function in microgravity which are needed to develop new applications of orbital research and future biotechnology.

  2. Thin film bioreactors in space

    Science.gov (United States)

    Hughes-Fulford, M.; Scheld, H. W.

    1989-01-01

    Studies from the Skylab, SL-3 and D-1 missions have demonstrated that biological organisms grown in microgravity have changes in basic cellular functions such as DNA, mRNA and protein synthesis, cytoskeleton synthesis, glucose utilization, and cellular differentiation. Since microgravity could affect prokaryotic and eukaryotic cells at a subcellular and molecular level, space offers an opportunity to learn more about basic biological systems with one inmportant variable removed. The thin film bioreactor will facilitate the handling of fluids in microgravity, under constant temperature and will allow multiple samples of cells to be grown with variable conditions. Studies on cell cultures grown in microgravity would make it possible to identify and quantify changes in basic biological function in microgravity which are needed to develop new applications of orbital research and future biotechnology.

  3. Silver: high performance anode for thin film lithium ion batteries

    Science.gov (United States)

    Taillades, G.; Sarradin, J.

    Among metals and intermetallic compounds, silver exhibits a high specific capacity according to the formation of different Ag-Li alloys (up to AgLi 12) in a very low voltage range versus lithium (0.250-0 V). Electrochemical results including Galvanostatic Intermittent Titration Technique (GITT) as well as cycling behaviour experiments confirmed the interesting characteristics of silver thin film electrodes prepared by radio frequency (r.f.) sputtering. XRD patterns recorded at different electrochemical stages of the alloying/de-alloying processes showed the complexity of the silver-lithium system under dynamic conditions. Cycling life depends on several parameters and particularly of the careful choice of cut-off voltages. In very well monitored conditions, galvanostatic cycles exhibited flat reversible plateaus with a minimal voltage value (0.050 V) between charge and discharge, a feature of great interest in the use of an electrode. The first results of a lithium ion battery with both silver and LiMn 1.5Ni 0.5O 4 thin films are presented.

  4. Morphology and oxygen incorporation effect on antimicrobial activity of silver thin films

    Science.gov (United States)

    Rebelo, Rita; Manninen, N. K.; Fialho, Luísa; Henriques, Mariana; Carvalho, Sandra

    2016-05-01

    Ag and AgxO thin films were deposited by non-reactive and reactive pulsed DC magnetron sputtering, respectively, with the final propose of functionalizing the SS316L substrate with antibacterial properties. The coatings were characterized chemically, physically and structurally. The coatings nanostructure was assessed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), while the coatings morphology was determined by scanning electron microscopy (SEM). The XRD and XPS analyses suggested that Ag thin film is composed by metallic Ag, which crystallizes in fcc-Ag phase, while the AgxO thin film showed both metallic Ag and Agsbnd O bonds, which crystalize in fcc-Ag and silver oxide phases. The SEM results revealed that Ag thin film formed a continuous layer, while AgxO layer was composed of islands with hundreds of nanometers surrounded by small nanoparticles with tens of nanometers. The surface wettability and surface tension parameters were determined by contact angle measurements, being found that Ag and AgxO surfaces showed very similar behavior, with all the surfaces showing a hydrophobic character. In order to verify the antibacterial behavior of the coatings, halo inhibition zone tests were realized for Staphylococcus epidermidis and Staphylococcus aureus. Ag coatings did not show antibacterial behavior, contrarily to AgxO coating, which presented antibacterial properties against the studied bacteria. The presence of silver oxide phase along with the development of different morphology was pointed as the main factors in the origin of the antibacterial effect found in AgxO thin film. The present study demonstrated that AgxO coating presented antibacterial behavior and its application in cardiovascular stents is promising.

  5. Stress evolution in copper-silver thin films during thermal-cycling

    Energy Technology Data Exchange (ETDEWEB)

    Chama, C.C., E-mail: ccchama1@yahoo.com [Department of Metallurgy and Mineral Processing, University of Zambia, P.O. Box 32379, Lusaka (Zambia); Vlassak, J.J. [School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138 (United States); Soboyejo, W.O. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer Stress in Cu and Cu-Ag films determined from -197 to 0 Degree-Sign C and RT to 400 Degree-Sign C. Black-Right-Pointing-Pointer Heating to 400 Degree-Sign C, films elastically and plastically deformed. Black-Right-Pointing-Pointer Cooling, Cu plastically deformed; Cu-Ag films plastic/elastic deformation. Black-Right-Pointing-Pointer At -197 to 0 Degree-Sign C, yielding did not occur in any Cu-6 at% Ag film. Black-Right-Pointing-Pointer Cu and Ag existed; grain growth and Ag coarsening occurred. - Abstract: Stress evolution in Cu, Cu-1.4 at% Ag, Cu-3 at% Ag and Cu-6 at% Ag thin films was determined by substrate curvature measurements from room temperature to 400 Degree-Sign C in two cycles, each involving a heating and a cooling stage. Stress hysteresis curves for the Cu-Ag films changed slope significantly within the temperature range 220-250 Degree-Sign C and stress range 100-200 MPa during the heating stage of the first cycle; this occurred at 175 Degree-Sign C and 100 MPa for the Cu film. This was followed by stress relaxation in all the films at about 300 Degree-Sign C. For the as-deposited, annealed and thermally cycled films exposed to low temperatures (-197 to 0 Degree-Sign C), instances of yielding occurred in Cu, Cu-1.4 at% Ag and Cu-3 at% Ag films. However, the as-deposited, annealed and thermally cycled Cu-6 at% Ag film was always elastic and there was no yielding when exposed to low temperatures. Microstructural analyses revealed the presence of Cu and Ag phases in all the Cu-Ag films, irrespective of the thermal history. Despite electron diffraction revealing their existence, Ag particles were not so apparent in the microstructures of the as-deposited and annealed films probably because of their fine sizes. However, after thermal-cycling Ag particles were observed at grain boundaries and inside grains in addition to significant grain growth.

  6. Broadband THz pulse emission and transmission properties of nanostructured Pt thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Mingzhe [Department of Physics and Electronics, Liupanshui Normal University, Liupanshui, Guizhou 553004 (China); College of Electronics and Information, Guizhou University, Huaxi 550025, Guiyang, Guizhou (China); Mu, Kaijun; Zhang, Cunlin [Department of Physics, Capital Normal University, Yuquan Road 100082, Beijing (China); Gu, Haoshuang, E-mail: guhs@hubu.edu.cn [Department of Electronic Sci& Tech, Hubei University, Xueyuan Road 430062, Wuhan, Hubei (China); Ding, Zhao [College of Electronics and Information, Guizhou University, Huaxi 550025, Guiyang, Guizhou (China)

    2015-10-01

    The THz transmission and emitting properties of a composite metallic nanostructure, composed of Ag nanowires electrodeposited in an anodic aluminum oxide (AAO) template and a Pt thin film, were investigated by using a femtosecond pulse laser irradiation. The microstructure of the above sub-wavelength nanostructure was investigated by XRD, SEM, AFM and TEM. The results indicated that the thickness of the Pt thin film was about 200 nm and the Ag nanowire array had a sparse and random distribution inside the AAO template, with a length distribution in the range of 10–25 μm. The THz radiation properties of above sub-wavelength nanostructure indicated that the generated THz fluence from the Pt film was a magnitude of μW scale with a broadband frequency range and its subsequent transmission could be significantly improved by the better impedance matching property of the Ag nanowire embedded AAO film compared with that of the empty AAO film.

  7. Magnetization in permalloy thin films

    Indian Academy of Sciences (India)

    Rachana Gupta; Mukul Gupta; Thomas Gutberlet

    2008-11-01

    Thin films of permalloy (Ni80Fe20) were prepared using an Ar+N2 mixture with magnetron sputtering technique at ambient temperature. The film prepared with only Ar gas shows reflections corresponding to the permalloy phase in X-ray diffraction (XRD) pattern. The addition of nitrogen during sputtering results in broadening of the peaks in XRD pattern, which finally leads to an amorphous phase. The - loop for the sample prepared with only Ar gas is matching well with the values obtained for the permalloy. For the samples prepared with increased nitrogen partial pressure the magnetic moment decreased rapidly and the values of coercivity increased. The polarized neutron reflectivity measurements (PNR) were performed in the sample prepared with only Ar gas and with nitrogen partial pressure of 5 and 10%. It was found that the spin-up and spin-down reflectivities show exactly similar reflectivity for the sample prepared with Ar gas alone, while PNR measurements on 5 and 10% sample show splitting in the spin-up and spin-down reflectivity.

  8. Micromotors using magnetostrictive thin films

    Science.gov (United States)

    Claeyssen, Frank; Le Letty, Ronan; Barillot, Francois; Betz, Jochen; MacKay, Ken; Givord, Dominique; Bouchilloux, Philippe

    1998-07-01

    This study deals with a micromotor based on the use of magnetostrictive thin films. This motor belongs to the category of the Standing Wave Ultrasonic Motors. The active part of the motor is the rotor, which is a 100 micrometers thick ring vibrating in a flexural mode. Teeth (300 micrometers high) are placed on special positions of the rotor and produce an oblique motion which can induce the relative motion of any object in contact with them. The magnetic excitation field is radial and uses the transverse coupling of the 4 micrometers thick magnetostrictive film. The film, deposited by sputtering on the ring, consists of layers of different rare-earth/iron alloys and was developed during a European Brite-Euram project. The finite element technique was used in order to design a prototype of the motor and to optimize the active rotor and the energizer coil. The prototype we built delivered a speed of 30 turns per minute with a torque of 2 (mu) N.m (without prestress applied on the rotor). Our experimental results show that the performance of this motor could easily be increased by a factor of 5. The main advantage of this motor is the fact that it is remotely powered and controlled. The excitation coil, which provides both power and control, can be placed away from the active rotor. Moreover, the rotor is completely wireless and is not connected to its support or to any other part. It is interesting to note that it would not be possible to build this type of motor using piezoelectric technology. Medical applications of magnetostrictive micromotors could be found for internal microdistributors of medication (the coil staying outside the body). Other applications include remote control micropositioning, micropositioning of optical components, and for the actuation of systems such as valves, electrical switches, and relays.

  9. Modification of polyamide-CdS-CdSe composite material films with Ag using a cation–cation exchange reaction

    Energy Technology Data Exchange (ETDEWEB)

    Krylova, V.; Žalenkienė, S.; Dukstienė, N. [Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Radvilenu st. 19, LT-50254, Kaunas (Lithuania); Baltrusaitis, J., E-mail: job314@lehigh.edu [Department of Chemical and Biomolecular Engineering, Lehigh University, B336 Iacocca Hall, 111 Research Drive, Bethlehem, PA 18015 (United States)

    2015-10-01

    Highlights: • We investigated deposition of a mixed CdSe-CdS-Ag{sub 2}Se-Ag{sub 2}S on polyamide. • A single chalcogen precursor – K{sub 2}SeS{sub 2}O{sub 6} – was used. • AAS showed five- to ten-fold excess of chalcogens diffused into PA. • Addition of AgNO{sub 3} resulted in subsurface Ag{sub 2}Se–Ag{sub 2}S formation. - Abstract: Thin mixed CdSe-CdS-Ag{sub 2}Se-Ag{sub 2}S films were deposited on a polyamide 6 (PA) surface by successfully using a cation-exchange reaction between Cd{sup 2+} and Ag{sup +} to convert CdSe-CdS into Ag{sub 2}Se-Ag{sub 2}S. These were deposited using a K{sub 2}SeS{sub 2}O{sub 6} precursor solution at 60 °C followed by cadmium acetate (Cd(CH{sub 3}COO){sub 2}). An aqueous AgNO{sub 3} solution was used as the Ag source. XRD patterns showed a complex PA-Cd-S-Se-Ag film crystalline composition with CdS, CdSe, Ag{sub 2}S and Ag{sub 2}Se peaks. Calculated dislocation density ranged within 5–15 × 10{sup 13} lines·m{sup −2} indicating high quality atomic layers. Atomic Absorption Spectroscopy (AAS) showed five- to ten-fold excess of chalcogens to metals in the thin films formed. No chalcogenides were observed on the sample surface during XPS analysis after Ag exchange due to the desorption of CdS and CdSe layers, not diffused into the bulk of the polymer suggesting that silver chalcogenides were located subsurface, as opposed to the outermost layer, likely comprised of Ag{sub 2}O.

  10. TiO2 thin film photocatalyst

    Institute of Scientific and Technical Information of China (English)

    YU Jiaguo

    2004-01-01

    It is well known that the photocatalytic activity of TiO2 thin films strongly depends on the preparing methods and post-treatment conditions, since they have a decisive influence on the chemical and physical properties of TiO2 thin films.Therefore, it is necessary to elucidate the influence of the preparation process and post-treatment conditions on the photocatalytic activity and surface microstructures of the films. This review deals with the preparation of TiO2 thin film photocatalysts by wet-chemical methods (such as sol-gel, reverse micellar and liquid phase deposition) and the comparison of various preparation methods as well as their advantage and disadvantage. Furthermore, it is discussed that the advancement of photocatalytic activity, super-hydrophilicity and bactericidal activity of TiO2 thin film photocatalyst in recent years.

  11. Surface plasmon exciton transition in ultra-thin silver and silver iodide films

    Science.gov (United States)

    Bharathi Mohan, D.; Sreejith, K.; Sunandana, C. S.

    2007-10-01

    Silver thin films in the thickness range 2 10 nm produced by thermal evaporation onto glass substrates were systematically iodized and carefully characterized by X-ray diffraction, atomic force microscopy (AFM) and optical absorption spectroscopy. While the uniodized films are X-ray amorphous in keeping with their quasi-continuous nature and 2D islanded structure, briefly iodized films showed characteristic beta AgI structure. Most interestingly, AFM of Ag films revealed uniform triangle-shaped embryos whose shape does not change appreciably upon iodization. Optical absorption spectra of uniodized Ag films show intense surface plasmon resonance (SPR) features with maxima at 440, 484 and 498 nm for the films of thicknesses 2, 5 and 10 nm, respectively, with 5 nm films showing properties characteristic of optimally matched dielectric and electronic properties of the substrate and sample, respectively. Finally, an interesting and unique SPR exciton phase transition is observed as the ultra-thin films are progressively iodized. These Ag and AgI films could be promising candidates for plasmonic and nanophotonic applications.

  12. Interfacial Effects on Pentablock Ionomer Thin Films

    Science.gov (United States)

    Etampawala, Thusitha; Ratnaweera, Dilru; Osti, Naresh; Shrestha, Umesh; Perahia, Dvora; Majewski, Jaroslaw

    2011-03-01

    The interfacial behavior of multi block copolymer thin films results from a delicate balance between inherent phase segregation due to incompatibility of the blocks and the interactions of the individual blocks with the interfaces. Here in we report a study of thin films of ABCBA penta block copolymers, anionically synthesized, comprising of centered randomly sulfonated polystyrene block to which rubbery poly-ethylenebutalene is connected, terminated by blocks of poly-t-butylstyrene, kindly provided by Kraton. AFM and neutron reflectometry studies have shown that the surface structure of pristine films depends on film thickness and ranges from trapped micelles to thin layered films. Annealing above Tg for the styrene block results in rearrangements into relatively featureless air interface. Neutron reflectivity studies have shown that annealed films forms layers whose plane are parallel to the solid substrate with the bulky block at the air interface and the ionic block at the solid interface.

  13. Optical and Short-wavelength Recording Properties of Ag8In14Sb55Te23 Phase-change Films

    Institute of Scientific and Technical Information of China (English)

    LI Jinyan; HOU Lisong; GAN Fuxi

    2001-01-01

    The Ag-In-Sb-Te phase-change films were deposited on K9 glass substrates by RF magnetron sputtering technology with an Ag-In-Sb-Te alloy target. The spectral properties and short-wavelength optical storage properties of Ag8In13Sb55Te23 films were studied. X-ray diffraction results have indicated that the crystallization compounds include mainly AgSbTe2 with small amounts of Sb and AgInTe2. A comparatively large absorption has been observed in the visible wavelength range. The optical storage characteristics of Ag8In13Sb55Te23 thin films indicated that larger reflectivity contrast can be obtained at lower writing power and shorter writing pulse width.

  14. Anisotropic Heisenberg model in thin film geometry

    Energy Technology Data Exchange (ETDEWEB)

    Akıncı, Ümit

    2014-01-01

    The effect of the anisotropy in the exchange interaction on the phase diagrams and magnetization behavior of the Heisenberg thin film has been investigated with effective field formulation in a two spin cluster using the decoupling approximation. Phase diagrams and magnetization behaviors have been obtained for several different cases, by grouping the systems in accordance with, whether the surfaces/interior of the film has anisotropic exchange interaction or not. - Highlights: • Phase diagrams of the anisotropic Heisenberg model on the thin film obtained • Dependence of the critical properties on the film thickness obtained • Effect of the anisotropy on the magnetic properties obtained.

  15. Insect thin films as solar collectors.

    Science.gov (United States)

    Heilman, B D; Miaoulis, L N

    1994-10-01

    A numerical method for simulation of microscale radiation effects in insect thin-film structures is described. Accounting for solar beam and diffuse radiation, the model calculates the reflectivity and emissivity of such structures. A case study examines microscale radiation effects in butterfuly wings, and results reveal a new function of these multilayer thin films: thermal regulation. For film thicknesses of the order of 0.10 µm, solar absorption levels vary by as much as 25% with small changes in film thickness; for certain existing structures, absorption levels reach 96%., This is attributed to the spectral distribution of the reflected radiation, which consists of a singular reflectance peak within the solar spectrum.

  16. Magnetic Surfaces, Thin Films, and Multilayers

    Science.gov (United States)

    1992-01-01

    PERPENDICULAR MAGNETIC ANISOTROPY AND MAGNETO-OPTICS * PERPENDICULAR MAGNETIC ANISOTROPY OF Pd/Co AND RELATED MULTILAYERS 441 S...THE PERPENDICULAR MAGNETIC ANISOTROPY AND STRUCTURE OF SPUTTERED Ag/Co, Pd/Co, AND AgPd/Co MULTILAYERED FILMS 473 Akira Yamaguchi, We-Hyo Soe, Ryoichi...the magnetic phase transi- tion and magnetic anisotropy, has attracted considerable interest. Theoretical predictions on perpendicular magnetic anisotropy

  17. Characterization of nanostructured TiO2:Ag films: structural and optical properties

    Science.gov (United States)

    Ivanova, T.; Harizanova, A.; Koutzarova, T.; Vertruyen, B.

    2016-10-01

    TiO2:Ag nanocomposites have been prepared by sol-gel method with varying silver concentration. Different technological approaches are employed to study the formation of Ag nanoparticles in titanium dioxide matrix. The obtained thin films are either thermally treated at temperatures from 300 to 600oC or UV irradiated for 15 minutes between layer deposition. XRD and FTIR studies reveal that Ag is incorporated in TiO2 films as nanoparticles and no Ag oxide phases are detected. Optical characterization performed by UV-VIS spectroscopy confirms the formation of silver nanoparticles. The influence of thermal treatment and UV radiation on the optical and structural properties is studied.

  18. Ferromagnetic properties of fcc Gd thin films

    Energy Technology Data Exchange (ETDEWEB)

    Bertelli, T. P., E-mail: tambauh@gmail.com; Passamani, E. C.; Larica, C.; Nascimento, V. P.; Takeuchi, A. Y. [Universidade Federal do Espírito Santo, Departamento de Física, Vitória/ES 29075-910 (Brazil); Pessoa, M. S. [Universidade Federal do Espírito Santo, Departamento de Ciências Naturais, São Mateus/ES 29932-540 (Brazil)

    2015-05-28

    Magnetic properties of sputtered Gd thin films grown on Si (100) substrates kept at two different temperatures were investigated using X-ray diffraction, ac magnetic susceptibility, and dc magnetization measurements. The obtained Gd thin films have a mixture of hcp and fcc structures, but with their fractions depending on the substrate temperature T{sub S} and film thickness x. Gd fcc samples were obtained when T{sub S} = 763 K and x = 10 nm, while the hcp structure was stabilized for lower T{sub S} (300 K) and thicker film (20 nm). The fcc structure is formed on the Ta buffer layer, while the hcp phase grows on the fcc Gd layer as a consequence of the lattice relaxation process. Spin reorientation phenomenon, commonly found in bulk Gd species, was also observed in the hcp Gd thin film. This phenomenon is assumed to cause the magnetization anomalous increase observed below 50 K in stressed Gd films. Magnetic properties of fcc Gd thin films are: Curie temperature above 300 K, saturation magnetization value of about 175 emu/cm{sup 3}, and coercive field of about 100 Oe at 300 K; features that allow us to classify Gd thin films, with fcc structure, as a soft ferromagnetic material.

  19. Enhanced photocatalytic activity of silver nanoparticles modified TiO{sub 2} thin films prepared by RF magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Meng Fanming, E-mail: mrmeng@ahu.edu.cn [School of Physics and Materials Science, Anhui University, Hefei 230039 (China); State Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Dalian 116024 (China); Anhui Key Laboratory of Information Materials and Devices, Anhui University, Hefei 230039 (China); Sun Zhaoqi [School of Physics and Materials Science, Anhui University, Hefei 230039 (China); Anhui Key Laboratory of Information Materials and Devices, Anhui University, Hefei 230039 (China)

    2009-12-15

    Ag-TiO{sub 2} nanostructured thin films with silver volume fraction of 0-40% were prepared by RF magnetron sputtering. The microstructure, surface topography, and optical properties of the films were characterized by X-ray diffractometer, transmission electron microscope, and ultraviolet-visible spectrophotometer. Photocatalytic activity of the films was evaluated by light-induced degradation of methyl orange (C{sub 14}H{sub 14}N{sub 3}NaO{sub 3}S) solution using a high pressure mercury lamp as lamp-house. The relation of photocatalytic activity and silver content was studied in detail. It is found that silver content influences microstructure of TiO{sub 2} thin films, and silver in the films is metallic Ag (Ag{sup 0}). Photocatalytic activity of the films increases with increasing silver content up to 5 vol.% Ag and then decreases to values significantly still bigger than that of pure TiO{sub 2} thin films. Silver nanoparticles significantly enhance the photocatalytic activity of TiO{sub 2} films. The better separation between electrons and holes on silver modified TiO{sub 2} thin films surface allowed more efficiency for the oxidation and reduction reactions. The enhanced photocatalytic activity was mainly attributed to the decrease of energy gap of the films and the increase of oxygen anion radicals O{sub 2}{sup -} and reactive center of surface Ti{sup 3+} on silver modified TiO{sub 2} thin films surface.

  20. Effect of different substrate on optical properties of Se92Te4Ag4 films

    Science.gov (United States)

    Singh, D.; Kumar, S.; Thangaraj, R.

    2014-01-01

    Present work reports the effect of substrate on the optical properties of Se92Te4Ag4 thin films. Thin films of thickness 2500 Å were prepared by the thermal evaporation of the bulk samples. Amorphous nature of thin films is confirmed by the X-ray diffraction spectra. The transmittance spectra of Se92Te4Ag4 thin films were obtained in the spectral region in the range 300-1100 nm. The optical band gap (Eg) and extinction coefficient (k) has been calculated from the absorbance data. The value of refractive index (n) has been determined from Swanepoel's method. The band gap of the film deposited on mica substrate (1.24 eV) is smallest as compared to the band gap of the films deposited on microscopic glass (1.29 eV) and quartz (1.26 eV). The change in value of optical parameters with change in substrate is explained in terms of disorder and defects, which confirms the dependence of optical parameters on types of substrates.

  1. Laser nanostructuring of Au/Ag and Au/Ni films for application in SERS

    Science.gov (United States)

    Nikov, Ru. G.; Nedyalkov, N. N.; Atanasov, P. A.; Grochowska, K.; Iwulska, A.; Sliwinski, G.

    2013-03-01

    In this paper results on laser nanostructuring of Au/Ag and Au/Ni thin films are presented. The nanostructuring leads to formation of arrays of bimetallic nanoparticles. The fabrication of the these structures is made using a two step procedure. Initially, thin films are deposited on quartz substrates by classical pulsed laser deposition method. In order to produce Au/Ag or Au/Ni thin films, targets with two sections consist the different metals are used. Thin films with different concentrations of the two metals are obtained by changing the area of the different sections in the target. The as prepared films are then annealed by nanosecond laser pulses delivered by Nd:YAG laser system operated at λ = 355 nm. It is found that the laser annealing may lead to nanostructuring of the deposited films as at certain conditions decomposition into monolayers of nanoparticles with narrow size distribution is obtained. The performed EDX analyses indicate that the fabricated particles are composed by a bimetallic system of the basic metals used. The transmission spectra of the obtained structures show evidences of plasmon excitations. The bimetal nanostructures are covered with Rhodamine 6G and then tested as active substrates for Surface Enhanced Raman Spectroscopy (SERS).

  2. Highly stretchable wrinkled gold thin film wires

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Joshua, E-mail: joshuk7@uci.edu; Park, Sun-Jun; Nguyen, Thao [Department of Chemical Engineering and Materials Science, University of California, Irvine, California 92697 (United States); Chu, Michael [Department of Biomedical Engineering, University of California, Irvine, California 92697 (United States); Pegan, Jonathan D. [Department of Materials and Manufacturing Technology, University of California, Irvine, California 92697 (United States); Khine, Michelle, E-mail: mkhine@uci.edu [Department of Chemical Engineering and Materials Science, University of California, Irvine, California 92697 (United States); Department of Biomedical Engineering, University of California, Irvine, California 92697 (United States)

    2016-02-08

    With the growing prominence of wearable electronic technology, there is a need to improve the mechanical reliability of electronics for more demanding applications. Conductive wires represent a vital component present in all electronics. Unlike traditional planar and rigid electronics, these new wearable electrical components must conform to curvilinear surfaces, stretch with the body, and remain unobtrusive and low profile. In this paper, the piezoresistive response of shrink induced wrinkled gold thin films under strain demonstrates robust conductive performance in excess of 200% strain. Importantly, the wrinkled metallic thin films displayed negligible change in resistance of up to 100% strain. The wrinkled metallic wires exhibited consistent performance after repetitive strain. Importantly, these wrinkled thin films are inexpensive to fabricate and are compatible with roll to roll manufacturing processes. We propose that these wrinkled metal thin film wires are an attractive alternative to conventional wires for wearable applications.

  3. Thin films for geothermal sensing: Final report

    Energy Technology Data Exchange (ETDEWEB)

    1987-09-01

    The report discusses progress in three components of the geothermal measurement problem: (1) developing appropriate chemically sensitive thin films; (2) discovering suitably rugged and effective encapsulation schemes; and (3) conducting high temperature, in-situ electrochemical measurements. (ACR)

  4. Manganese ferrite thin films Part II: Properties

    NARCIS (Netherlands)

    Hulscher, W.S.

    1972-01-01

    Some properties of evaporated manganese ferrite thin films are investigated, e.g. resistivity, magnetization reversal, Curie temperature, Faraday rotation and optical absorption. The properties are partly related to the partial oxygen pressure present during a preceding annealing process.

  5. Photocatalytic Ag-TiO2 Thin Films Prepared by RF Magnetron Co-Sputtering%射频磁控共溅射制备光催化Ag-TiO2薄膜

    Institute of Scientific and Technical Information of China (English)

    沈杰; 蔡臻炜; 沃松涛; 崔晓莉; 任达森; 杨锡良; 章壮健

    2005-01-01

    采用射频磁控共溅射法制备Ag-TiO2复合薄膜,通过控制Ag靶的溅射时间可调节Ag与TiO2的比例.所制备的Ag-TiO2薄膜为锐钛矿结构.通过紫外光照降解亚甲基蓝溶液和循环伏安法研究Ag-TiO2薄膜光催化及光电化学特性.实验结果表明:掺1.5% Ag的Ag-TiO2薄膜在紫外光照射下能增强亚甲基蓝溶液的降解并得到更大的光生电流.这种光催化的增强主要是由于光生电子-空穴对的复合被抑制的结果.

  6. Scattering of long wavelengths into thin silicon photovoltaic films by plasmonic silver nanoparticles

    Science.gov (United States)

    Osgood, R. M.; Bullion, K. M.; Giardini, S. A.; Carlson, J. B.; Stenhouse, P.; Kingsborough, R.; Liberman, V.; Parameswaran, L.; Rothschild, M.; Miller, O.; Kooi, S.; Joannopoulos, J.; Jeffrey, F.; Braymen, S.; Gill, H. Singh; Kumar, J.

    2014-10-01

    Nanoparticles and nanostructures with plasmonic resonances are currently being employed to enhance the efficiency of solar cells. 1-3 Ag stripe arrays have been shown theoretically to enhance the short-circuit current of thin silicon layers. 4 Monolayers of Ag nanoparticles with diameter d thin polymer layers with thicknesses thin (100 nm films deposited on glass and flexible polymer substrates, the latter originating in a roll-to-roll manufacturing process. Ag nanoparticles are held in place and aggregation is prevented with a polymer overcoat. We observe interesting wavelength shifts between maxima in specular and diffuse scattering that depend on particle size and shape, indicating that the nanoparticles substantially modify the scattering into the thin silicon film.

  7. Thin solid-lubricant films in space

    Science.gov (United States)

    Roberts, E. W.

    Low-friction films of thickness as low as 1 micron, created through sputter-deposition of low shear strength materials, are required in spacecraft applications requiring low power dissipation, such as cryogenic devices, and low torque noise, such as precision-pointing mechanisms. Due to their thinness, these coatings can be applied to high precision-machined tribological components without compromising their functional accuracy. Attention is here given to the cases of thin solid films for ball bearings, gears, and journal bearings.

  8. Studies in thin film flows

    CERN Document Server

    McKinley, I S

    2000-01-01

    the general case of non-zero capillary number numerically. Using the lubrication approximation to the Navier-Stokes equations we investigate the evolution and stability of a thin film of incompressible Newtonian fluid on a planar substrate subjected to a jet of air blowing normally to the substrate. For the simple model of the air jet we adopt, the initially axisymmetric problems we study are identical to those of a drop spreading on a turntable rotating at constant angular velocity (the simplest model for spin coating). We consider both drops without a dry patch (referred to as 'non-annular') and drops with a dry patch at their centre (referred to as 'annular'). First, both symmetric two-dimensional and axisymmetric three-dimensional drops are considered in the quasi-static limit of small capillary number. The evolution of both non-annular and annular drops and the stability of equilibrium solutions to small perturbations with zero wavenumber are determined. Using a specially developed finite-difference code...

  9. Epitaxy, thin films and superlattices

    Energy Technology Data Exchange (ETDEWEB)

    Jagd Christensen, Morten

    1997-05-01

    This report is the result of structural investigations of 3d transition metal superlattices consisting of Fe/V, Cr/Mn, V/Mn and Fe/Mn, and a structural and magnetic study of a series of Ho/Pr alloys. The work includes preparation and characterization of substrates as well as growth of thin films and Fe/V superlattices by molecular beam epitaxy, including in-situ characterization by reflection high energy electron diffraction and Auger electron spectroscopy. Structural characterization has been done by x-ray diffraction and neutron diffraction. The x-ray diffraction experiments have been performed on the rotating copper anode at Risoe, and at synchrotron facilities in Hamburg and Brookhaven, and the neutron scattering was done at the Danish research reactor DR3 at Risoe. In addition to longitudinal scans, giving information about the structural parameters in the modulation direction, non-specular scans were also performed. This type of scans gives information about in-plane orientation and lattice parameters. From the analysis, structural information is obtained about lattice parameters, epitaxial strain, coherence lengths and crystallographic orientation for the superlattice systems, except Fe/Mn superlattices, which could not be modelled. For the Ho/Pr alloys, x-ray magnetic scattering was performed, and the crystal and magnetic structure was investigated. (au) 14 tabs.; 58 ills., 96 refs.

  10. Ag films grown by remote plasma enhanced atomic layer deposition on different substrates

    Energy Technology Data Exchange (ETDEWEB)

    Amusan, Akinwumi A., E-mail: akinwumi.amusan@ovgu.de; Kalkofen, Bodo; Burte, Edmund P. [Institute of Micro and Sensor Systems, Otto-von-Guericke University, Universitätsplatz 2, 39106 Magdeburg (Germany); Gargouri, Hassan; Wandel, Klaus; Pinnow, Cay [SENTECH Instruments GmbH, Schwarzschildstraße 2, 12489 Berlin (Germany); Lisker, Marco [IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany)

    2016-01-15

    Silver (Ag) layers were deposited by remote plasma enhanced atomic layer deposition (PALD) using Ag(fod)(PEt{sub 3}) (fod = 2,2-dimethyl-6,6,7,7,8,8,8-heptafluorooctane-3,5-dionato) as precursor and hydrogen plasma on silicon substrate covered with thin films of SiO{sub 2}, TiN, Ti/TiN, Co, Ni, and W at different deposition temperatures from 70  to 200 °C. The deposited silver films were analyzed by x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) with energy dispersive x-ray spectroscopy, four point probe measurement, ellipsometric measurement, x-ray fluorescence (XRF), and x-ray diffraction (XRD). XPS revealed pure Ag with carbon and oxygen contamination close to the detection limit after 30 s argon sputtering for depositions made at 120 and 200 °C substrate temperatures. However, an oxygen contamination was detected in the Ag film deposited at 70 °C after 12 s argon sputtering. A resistivity of 5.7 × 10{sup −6} Ω cm was obtained for approximately 97 nm Ag film on SiO{sub 2}/Si substrate. The thickness was determined from the SEM cross section on the SiO{sub 2}/Si substrate and also compared with XRF measurements. Polycrystalline cubic Ag reflections were identified from XRD for PALD Ag films deposited at 120 and 200 °C. Compared to W surface, where poor adhesion of the films was found, Co, Ni, TiN, Ti/TiN and SiO{sub 2} surfaces had better adhesion for silver films as revealed by SEM, TEM, and AFM images.

  11. Synthesis of Photochromic AgCl-Urethane Resin Composite Films

    Directory of Open Access Journals (Sweden)

    Hidetoshi Miyazaki

    2012-01-01

    Full Text Available AgCl-resin photochromic composite films were prepared using AgNO3, HCl-EtOH, CuCl2 solution, and a liquid-state urethane resin as starting materials. The obtained composite films showed a photochromic property. The rate of darkening of the composite film increased after mixing with CuCl2. The AgCl particle size in the film without heat treatment was 6–20 nm, and that of the heat-treated film was 25–80 nm; these results were confirmed using TEM observations. The fading rate of the film without heat treatment was higher than that of the heat-treated films.

  12. Carbon Nanotube Thin-Film Antennas.

    Science.gov (United States)

    Puchades, Ivan; Rossi, Jamie E; Cress, Cory D; Naglich, Eric; Landi, Brian J

    2016-08-17

    Multiwalled carbon nanotube (MWCNT) and single-walled carbon nanotube (SWCNT) dipole antennas have been successfully designed, fabricated, and tested. Antennas of varying lengths were fabricated using flexible bulk MWCNT sheet material and evaluated to confirm the validity of a full-wave antenna design equation. The ∼20× improvement in electrical conductivity provided by chemically doped SWCNT thin films over MWCNT sheets presents an opportunity for the fabrication of thin-film antennas, leading to potentially simplified system integration and optical transparency. The resonance characteristics of a fabricated chlorosulfonic acid-doped SWCNT thin-film antenna demonstrate the feasibility of the technology and indicate that when the sheet resistance of the thin film is >40 ohm/sq no power is absorbed by the antenna and that a sheet resistance of antenna. The dependence of the return loss performance on the SWCNT sheet resistance is consistent with unbalanced metal, metal oxide, and other CNT-based thin-film antennas, and it provides a framework for which other thin-film antennas can be designed.

  13. Photophysical properties of Alq3 thin films

    Science.gov (United States)

    Zawadzka, A.; Płóciennik, P.; Strzelecki, J.; Łukasiak, Z.; Sahraoui, B.

    2013-11-01

    This work contains investigation results of the photophysical properties of aluminum (III) tris(8-hydroxyquinoline) thin films. The Alq3 thin films were successfully fabricated by Physical Vapor Deposition technique. The films were grown on transparent: (quartz and glass) and semiconductor (n-type silica) substrates kept at room temperature during the deposition process. Selected films were annealed after fabrication in ambient atmosphere for 12 h at the temperature equal to 100 °C and 150 °C. Morphology of the films was investigated by AFM technique. Photophysical properties were characterized via photoluminescence, transmission, second and third harmonic generation measurements. The thin films exhibit high structural quality regardless of the annealing process, but the stability of the film can be improved by using an appropriate temperature during the annealing process. Photoluminescence of Alq3 films obtained in air were efficient and stable. The measurements of transmission, SHG and THG spectra allowed us to determine optical constant of the films. We find that the photophysical properties were strictly connected with the morphology and the annealing process significantly changes the structural properties of the films.

  14. Thin-film crystalline silicon solar cells

    CERN Document Server

    Brendel, Rolf

    2011-01-01

    This introduction to the physics of silicon solar cells focuses on thin cells, while reviewing and discussing the current status of the important technology. An analysis of the spectral quantum efficiency of thin solar cells is given as well as a full set of analytical models. This is the first comprehensive treatment of light trapping techniques for the enhancement of the optical absorption in thin silicon films.

  15. Study on the photocatalytic decomposing ethylene by Ag/TiO2 thin film%Ag/TiO2光催化薄膜清除乙烯气体的研究

    Institute of Scientific and Technical Information of China (English)

    梁晓娟; 杨昕宇; 向卫东

    2005-01-01

    乙烯对果蔬的生长有积极的作用,它可以促进果蔬的成熟,使其变得香甜可口.但果蔬成熟后乙烯的存在又可以加速果蔬的熟化程度,使其变得脆弱、易腐烂.因此,清除乙烯将对果蔬保鲜产生积极的影响.本文采用溶胶-凝胶方法制备了TiO2及Ag/TiO2薄膜.利用气相色谱法通过在自制的反应器内进行检测清除乙烯的实验,比较了TiO2薄膜和Ag/TiO2薄膜的光催化清除乙烯性能.结果发现,TiO2薄膜有较好的光催化清除乙烯性能,掺杂适量的Ag后,Ag/TiO2薄膜有更好的清除乙烯性能.本文还用XRD、SEM对TiO2及Ag/TiO2薄膜的形貌、物相结构、颗粒尺寸进行了表征分析并对实验结果进行了讨论.

  16. A thin-film magnetoresistive angle detector

    NARCIS (Netherlands)

    Eijkel, Kees J.M.; Wieberdink, Johan W.; Fluitman, Jan H.J; Popma, Theo J.A.; Groot, Peter; Leeuwis, Henk

    1990-01-01

    An overview is given of the results of our research on a contactless angle detector based on the anisotropic magnetoresistance effect (AMR effect) in a permalloy thin film. The results of high-temperature annealing treatment of the pemalloy film are discussed. Such a treatment suppresses the effects

  17. Liquid phase deposition of electrochromic thin films

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Thomas J.; Rubin, Michael D.

    2000-08-18

    Thin films of titanium, zirconium and nickel oxides were deposited on conductive SnO2:F glass substrates by immersion in aqueous solutions. The films are transparent, conformal, of uniform thickness and appearance, and adhere strongly to the substrates. On electrochemical cycling, TiO2, mixed TiO2-ZrO2, and NiOx films exhibited stable electrochromism with high coloration efficiencies. These nickel oxide films were particularly stable compared with films prepared by other non-vacuum techniques. The method is simple, inexpensive, energy efficient, and readily scalable to larger substrates.

  18. Adhesion and friction of thin metal films

    Science.gov (United States)

    Buckley, D. H.

    1976-01-01

    Sliding friction experiments were conducted in vacuum with thin films of titanium, chromium, iron, and platinum sputter deposited on quartz or mica substrates. A single crystal hemispherically tipped gold slider was used in contact with the films at loads of 1.0 to 30.0 and at a sliding velocity of 0.7 mm/min at 23 C. Test results indicate that the friction coefficient is dependent on the adhesion of two interfaces, that between the film and its substrate and the slider and the film. There exists a relationship between the percent d bond character of metals in bulk and in thin film form and the friction coefficient. Oxygen can increase adhesive bonding of a metal film (platinum) to a substrate.

  19. Polymer surfaces, interfaces and thin films

    Energy Technology Data Exchange (ETDEWEB)

    Stamm, M. [Max-Planck-Institut fuer Polymerforschung, Mainz (Germany)

    1996-11-01

    Neutron reflectometry can be used in various ways to investigate surfaces, interfaces and thin films of polymers. Its potential comes mostly from the possibilities offered by selective deuteration, where a particular component can be made visible with respect to its activity at the interface. In addition the depth resolution is much better than with most other direct techniques, and details of the profiles may be resolved. Several examples will be discussed including the segment diffusion at the interface between two polymer films, the determination of the narrow interfaces between incompatible polymer blends and the development of order in thin diblock copolymer films. (author) 10 figs., 2 tabs., 38 refs.

  20. NLO properties of functionalized DNA thin films

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, Oksana [University d' Angers, Laboratoire POMA CNRS UMR 6136, France, 2 Bd. Lavoisier, 49045 (France)], E-mail: okrupka@mail.ru; El-ghayoury, Abdelkrim [University d' Angers, UFR Sciences, Laboratoire CIMMA UMR CNRS 6200, 2 Bd. Lavoisier, 49045 (France); Rau, Ileana; Sahraoui, Bouchta [University d' Angers, Laboratoire POMA CNRS UMR 6136, France, 2 Bd. Lavoisier, 49045 (France); Grote, James G. [Air Force Research Laboratory Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, 3005 Hobson Way, Dayton, OH 45433-7707 (United States); Kajzar, Francois [University d' Angers, Laboratoire POMA CNRS UMR 6136, France, 2 Bd. Lavoisier, 49045 (France)

    2008-10-31

    In this paper we investigate the third-order nonlinear optical properties of spin deposited thin films of DNA-based complexes using the optical third harmonic generation (THG) technique at a fundamental wavelength of 1064 nm. We found that the third-order susceptibility, {chi}{sup (3)}(- 3{omega};{omega},{omega},{omega}), of DNA-based films was about one order of magnitude larger than that of our reference, a pure silica slab. In thin films doped with 5% of the chromophore disperse red 1 (DR1), a two order of magnitude larger value of {chi}{sup (3)}(- 3{omega};{omega},{omega},{omega}) was observed.

  1. Autophagy induction by silver nanowires: A new aspect in the biocompatibility assessment of nanocomposite thin films

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Navin K. [Institute of Molecular Medicine, Trinity College Dublin (Ireland); Centre for Research on Adaptive Nanostructures and Nanodevices, Trinity College Dublin (Ireland); Conroy, Jennifer [Institute of Molecular Medicine, Trinity College Dublin (Ireland); Lyons, Philip E.; Coleman, Jonathan [Centre for Research on Adaptive Nanostructures and Nanodevices, Trinity College Dublin (Ireland); O' Sullivan, Mary P. [Institute of Molecular Medicine, Trinity College Dublin (Ireland); Kornfeld, Hardy [University of Massachusetts Medical School, Massachusetts (United States); Kelleher, Dermot [Institute of Molecular Medicine, Trinity College Dublin (Ireland); Volkov, Yuri, E-mail: yvolkov@tcd.ie [Institute of Molecular Medicine, Trinity College Dublin (Ireland); Centre for Research on Adaptive Nanostructures and Nanodevices, Trinity College Dublin (Ireland)

    2012-11-01

    Nanomaterials and their enabled products have increasingly been attracting global attention due to their unique physicochemical properties. Among these emerging products, silver nanowire (AgNW)-based thin films are being developed for their promising applications in next generation nanoelectronics and nanodevices. However, serious concerns remain about possible health and safety risks they may pose. Here, we employed a multi-modal systematic biocompatibility assessment of thin films incorporating AgNW. To represent the possible routes of nanomaterial entry during occupational or environmental exposure, we employed four different cell lines of epithelial, endothelial, gastric, and phagocytic origin. Utilizing a cell-based automated image acquisition and analysis procedure in combination with real-time impedance sensing, we observed a low level of cytotoxicity of AgNW, which was dependent on cell type, nanowire lengths, doses and incubation times. Similarly, no major cytotoxic effects were induced by AgNW-containing thin films, as detected by conventional cell viability and imaging assays. However, transmission electron microscopy and Western immunoblotting analysis revealed AgNW-induced autophasosome accumulation together with an upregulation of the autophagy marker protein LC3. Autophagy represents a crucial mechanism in maintaining cellular homeostasis, and our data for the first time demonstrate triggering of such mechanism by AgNW in human phagocytic cells. Finally, atomic force microscopy revealed significant changes in the topology of cells attaching and growing on these films as substrates. Our findings thus emphasize the necessity of comprehensive biohazard assessment of nanomaterials in modern applications and devices and a thorough analysis of risks associated with their possible contact with humans through occupational or environmental exposure. Highlights: ► Thin films containing nanomaterials are subject to increasing contact with humans. ► This

  2. Thin Ice Films at Mineral Surfaces.

    Science.gov (United States)

    Yeşilbaş, Merve; Boily, Jean-François

    2016-07-21

    Ice films formed at mineral surfaces are of widespread occurrence in nature and are involved in numerous atmospheric and terrestrial processes. In this study, we studied thin ice films at surfaces of 19 synthetic and natural mineral samples of varied structure and composition. These thin films were formed by sublimation of thicker hexagonal ice overlayers mostly produced by freezing wet pastes of mineral particles at -10 and -50 °C. Vibration spectroscopy revealed that thin ice films contained smaller populations of strongly hydrogen-bonded water molecules than in hexagonal ice and liquid water. Thin ice films at the surfaces of the majority of minerals considered in this work [i.e., metal (oxy)(hydr)oxides, phyllosilicates, silicates, volcanic ash, Arizona Test Dust] produced intense O-H stretching bands at ∼3400 cm(-1), attenuated bands at ∼3200 cm(-1), and liquid-water-like bending band at ∼1640 cm(-1) irrespective of structure and composition. Illite, a nonexpandable phyllosilicate, is the only mineral that stabilized a form of ice that was strongly resilient to sublimation in temperatures as low as -50 °C. As mineral-bound thin ice films are the substrates upon which ice grows from water vapor or aqueous solutions, this study provides new constraints from which their natural occurrences can be understood.

  3. 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.

  4. Carrier lifetimes in thin-film photovoltaics

    Science.gov (United States)

    Baek, Dohyun

    2015-09-01

    The carrier lifetimes in thin-film solar cells are reviewed and discussed. Shockley-Read-Hall recombination is dominant at low carrier density, Auger recombination is dominant under a high injection condition and high carrier density, and surface recombination is dominant under any conditions. Because the surface photovoltage technique is insensitive to the surface condition, it is useful for bulk lifetime measurements. The photoconductance decay technique measures the effective recombination lifetime. The time-resolved photoluminescence technique is very useful for measuring thin-film semiconductor or solar-cell materials lifetime, because the sample is thin, other techniques are not suitable for measuring the lifetime. Many papers have provided time-resolved photoluminescence (TRPL) lifetimes for copper-indium-gallium-selenide (CIGS) and CdTe thin-film solar cell. The TRPL lifetime strongly depends on open-circuit voltage and conversion efficiency; however, the TRPL life time is insensitive to the short-circuit current.

  5. Study of the Thin Film Pulse Transformer

    Institute of Scientific and Technical Information of China (English)

    LIU Bao-yuan; SHI Yu; WEN Qi-ye

    2005-01-01

    A new thin film pulse transformer for using in ISND and model systems is fabricated by a mask sputtering process. This novel pulse transformer consists of four I-shaped CoZrRe nanometer crystal magnetic-film cores and a Cu thin film coil, deposited on the micro-crystal glass substrate directly. The thickness of thin film core is between 1 and 3 μm, and the area is between 4mm×6 mm and 12mm×6 mm. The coils provide a relatively high induce of 0.8 μm and can be well operated in a frequency range of 0.001~20 MHz.

  6. Magnetoelectric thin film composites with interdigital electrodes

    Science.gov (United States)

    Piorra, A.; Jahns, R.; Teliban, I.; Gugat, J. L.; Gerken, M.; Knöchel, R.; Quandt, E.

    2013-07-01

    Magnetoelectric (ME) thin film composites on silicon cantilevers are fabricated using Pb(Zr0.52Ti0.45)O3 (PZT) films with interdigital transducer electrodes on the top side and FeCoSiB amorphous magnetostrictive thin films on the backside. These composites without any direct interface between the piezoelectric and magnetostrictive phase are superior to conventional plate capacitor-type thin film ME composites. A limit of detection of 2.6 pT/Hz1/2 at the mechanical resonance is determined which corresponds to an improvement of a factor of approximately 2.8 compared to the best plate type sensor using AlN as the piezoelectric phase and even a factor of approximately 4 for a PZT plate capacitor.

  7. Tungsten-doped thin film materials

    Science.gov (United States)

    Xiang, Xiao-Dong; Chang, Hauyee; Gao, Chen; Takeuchi, Ichiro; Schultz, Peter G.

    2003-12-09

    A dielectric thin film material for high frequency use, including use as a capacitor, and having a low dielectric loss factor is provided, the film comprising a composition of tungsten-doped barium strontium titanate of the general formula (Ba.sub.x Sr.sub.1-x)TiO.sub.3, where X is between about 0.5 and about 1.0. Also provided is a method for making a dielectric thin film of the general formula (Ba.sub.x Sr.sub.1-x)TiO.sub.3 and doped with W, where X is between about 0.5 and about 1.0, a substrate is provided, TiO.sub.2, the W dopant, Ba, and optionally Sr are deposited on the substrate, and the substrate containing TiO.sub.2, the W dopant, Ba, and optionally Sr is heated to form a low loss dielectric thin film.

  8. Antibacterial and Photodegradative Properties of Metal Doped TiO2 thin Films Under Visible Light.

    Science.gov (United States)

    Ogorevc, Jerneja Šauta; Tratar-Pirc, Elizabeta; Matoh, Lev; Peter, Bukovec

    2012-06-01

    Doped (Au, Ag) and undoped TiO2 thin films were prepared on soda-lime glass via the sol-gel method by dip-coating from TiCl4 precursor, followed by 30 minutes calcination at 500 °C to obtain transparent thin films with good adhesion to the substrate. XRD analysis showed that the particle size of samples heat treated at 500 °C was ~10 nm for all of the samples prepared, both doped and undoped ones. SEM images revealed that the thin film surface was homogeneous and nano-porous. The hydrophilicity of the thin films was estimated by contact angle measurements. The photodegradation rate of an aqueous solution of the azo dye Plasmocorinth B on the thin films was tested by in-situ UV-Vis spectroscopic measurements of the dye solution. The best photocatalytic activity under visible and UVA light was exhibited by undoped TiO2 thin films, whereas Au doped thin films were slightly less active. On the other hand, the best antimicrobial activity toward the E. coli strain DH5a under visible light was displayed by the Au/TiO2 thin films.

  9. MOF thin films: existing and future applications.

    Science.gov (United States)

    Shekhah, O; Liu, J; Fischer, R A; Wöll, Ch

    2011-02-01

    The applications and potentials of thin film coatings of metal-organic frameworks (MOFs) supported on various substrates are discussed in this critical review. Because the demand for fabricating such porous coatings is rather obvious, in the past years several synthesis schemes have been developed for the preparation of thin porous MOF films. Interestingly, although this is an emerging field seeing a rapid development a number of different applications on MOF films were either already demonstrated or have been proposed. This review focuses on the fabrication of continuous, thin porous films, either supported on solid substrates or as free-standing membranes. The availability of such two-dimensional types of porous coatings opened the door for a number of new perspectives for functionalizing surfaces. Also for the porous materials themselves, the availability of a solid support to which the MOF-films are rigidly (in a mechanical sense) anchored provides access to applications not available for the typical MOF powders with particle sizes of a few μm. We will also address some of the potential and applications of thin films in different fields like luminescence, QCM-based sensors, optoelectronics, gas separation and catalysis. A separate chapter has been devoted to the delamination of MOF thin films and discusses the potential to use them as free-standing membranes or as nano-containers. The review also demonstrates the possibility of using MOF thin films as model systems for detailed studies on MOF-related phenomena, e.g. adsorption and diffusion of small molecules into MOFs as well as the formation mechanism of MOFs (101 references).

  10. Photodegradation properties and optics of Ag/TiO{sub 2} films; Propiedades de fotodegradacion y opticas de peliculas Ag/TiO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Tirado G, S. [IPN, Escuela Superior de Fisica y Matematicas, San Pedro Zacatenco, 07738 Ciudad de Mexico (Mexico); Valenzuela Z, M. A., E-mail: tirado@esfm.ipn.mx [IPN, Escuela Superior de Ingenieria Quimica e Industrias Extractivas, Laboratorio de Catalisis y Materiales, San Pedro Zacatenco, 07738 Ciudad de Mexico (Mexico)

    2016-10-15

    In the thin semiconductor films of Ag/TiO{sub 2} the topographic properties were recorded by atomic force microscopy and the main parameters of roughness were determined; the optical properties were also recorded when determining their transmittance degree, their refractive indexes, their thickness and the bandwidth of the semiconductor Eg, both for pure TiO{sub 2} films and the modified Ag/TiO{sub 2} films with various layers of the Ag catalyst. The Ag/TiO{sub 2} films that were grown by sol-gel and repeated immersion, chemical technique that has been used in the development of thin film technology, were carried out in photo catalysis, when are used in photo degradation of methyl orange at an aqueous concentration of 14 ppm, once they are characterized with several techniques required to be able to explain the possible photo catalytic reactions at the solid-aqueous interface, when irradiated with UV; with the possible application in water treatment. The photoluminescence spectra of the prepared Ag/TiO{sub 2} samples are reported, which resulted in a green emission, characteristic of the visible, in addition to emissions in the UV range. (Author)

  11. Sprayed lanthanum doped zinc oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Bouznit, Y., E-mail: Bouznit80@gmail.com [Laboratory of Materials Study, Jijel University, Jijel 18000 (Algeria); Beggah, Y. [Laboratory of Materials Study, Jijel University, Jijel 18000 (Algeria); Ynineb, F. [Laboratory of Thin Films and Interface, University Mentouri, Constantine 25000 (Algeria)

    2012-01-15

    Lanthanum doped zinc oxide thin films were deposited on soda-lime glass substrates using a pneumatic spray pyrolysis technique. The films were prepared using different lanthanum concentrations at optimum deposition parameters. We studied the variations in structural, morphological and optical properties of the samples due to the change of doping concentration in precursor solutions. X-ray diffraction (XRD) patterns show that pure and La-doped ZnO thin films are highly textured along c-axis perpendicular to the surface of the substrate. Scanning electron micrographs show that surface morphology of ZnO films undergoes a significant change according to lanthanum doping. All films exhibit a transmittance higher than 80% in the visible region.

  12. Sprayed lanthanum doped zinc oxide thin films

    Science.gov (United States)

    Bouznit, Y.; Beggah, Y.; Ynineb, F.

    2012-01-01

    Lanthanum doped zinc oxide thin films were deposited on soda-lime glass substrates using a pneumatic spray pyrolysis technique. The films were prepared using different lanthanum concentrations at optimum deposition parameters. We studied the variations in structural, morphological and optical properties of the samples due to the change of doping concentration in precursor solutions. X-ray diffraction (XRD) patterns show that pure and La-doped ZnO thin films are highly textured along c-axis perpendicular to the surface of the substrate. Scanning electron micrographs show that surface morphology of ZnO films undergoes a significant change according to lanthanum doping. All films exhibit a transmittance higher than 80% in the visible region.

  13. Thermal conductivity of nanoscale thin nickel films

    Institute of Scientific and Technical Information of China (English)

    YUAN Shiping; JIANG Peixue

    2005-01-01

    The inhomogeneous non-equilibrium molecular dynamics (NEMD) scheme is applied to model phonon heat conduction in thin nickel films. The electronic contribution to the thermal conductivity of the film is deduced from the electrical conductivity through the use of the Wiedemann-Franz law. At the average temperature of T = 300 K, which is lower than the Debye temperature ()D = 450 K,the results show that in a film thickness range of about 1-11 nm, the calculated cross-plane thermal conductivity decreases almost linearly with the decreasing film thickness, exhibiting a remarkable reduction compared with the bulk value. The electrical and thermal conductivities are anisotropic in thin nickel films for the thickness under about 10 nm. The phonon mean free path is estimated and the size effect on the thermal conductivity is attributed to the reduction of the phonon mean free path according to the kinetic theory.

  14. Magnetowetting of Ferrofluidic Thin Liquid Films

    Science.gov (United States)

    Tenneti, Srinivas; Subramanian, Sri Ganesh; Chakraborty, Monojit; Soni, Gaurav; Dasgupta, Sunando

    2017-03-01

    An extended meniscus of a ferrofluid solution on a silicon surface is subjected to axisymmetric, non-uniform magnetic field resulting in significant forward movement of the thin liquid film. Image analyzing interferometry is used for accurate measurement of the film thickness profile, which in turn, is used to determine the instantaneous slope and the curvature of the moving film. The recorded video, depicting the motion of the film in the Lagrangian frame of reference, is analyzed frame by frame, eliciting accurate information about the velocity and acceleration of the film at any instant of time. The application of the magnetic field has resulted in unique changes of the film profile in terms of significant non-uniform increase in the local film curvature. This was further analyzed by developing a model, taking into account the effect of changes in the magnetic and shape-dependent interfacial force fields.

  15. Optical Constants of Cadmium Telluride Thin Film

    Science.gov (United States)

    Nithyakalyani, P.; Pandiaraman, M.; Pannir, P.; Sanjeeviraja, C.; Soundararajan, N.

    2008-04-01

    Cadmium Telluride (CdTe) is II-VI direct band gap semiconductor compound with potential application in Solar Energy conversion process. CdTe thin film of thickness 220 mn was prepared by thermal evaporation technique at a high vacuum better than 10-5 m.bar on well cleaned glass substrates of dimensions (l cm×3 cm). The transmittance spectrum and the reflectance spectrum of the prepared CdTc thin film was recorded using UV-Vis Spectrophotometer in the wavelength range between 300 nm and 900 nm. These spectral data were analyzed and the optical band and optical constants of CdTe Thin film have been determined by adopting suitable relations. The optical band gap of CdTe thin film is found to be 1.56 eV and this value is also agreeing with the published works of CdTe thin film prepared by various techniques. The absorption coefficient (α) has been higher than 106 cm-1. The Refractive index (n) and the Extinction Coefficient (k) are found to be varying from 3.0 to 4.0 and 0.1 Cm-1 to 0.5 Cm-1 respectively by varying the energy from l.0 eV to 4.0 eV. These results are also compared with the literature.

  16. Pulsed laser deposition of ferroelectric thin films

    Science.gov (United States)

    Sengupta, Somnath; McKnight, Steven H.; Sengupta, Louise C.

    1997-05-01

    It has been shown that in bulk ceramic form, the barium to strontium ratio in barium strontium titanium oxide (Ba1- xSrxTiO3, BSTO) affects the voltage tunability and electronic dissipation factor in an inverse fashion; increasing the strontium content reduces the dissipation factor at the expense of lower voltage tunability. However, the oxide composites of BSTO developed at the Army Research Laboratory still maintain low electronic loss factors for all compositions examined. The intent of this study is to determine whether such effects can be observed in the thin film form of the oxide composites. The pulsed laser deposition (PLD) method has been used to deposit the thin films. The different compositions of the compound (with 1 wt% of the oxide additive) chosen were: Ba0.3Sr0.7TiO3, Ba0.4Sr0.6TiO3, Ba0.5Sr0.5TiO3, Ba0.6Sr0.4TiO3, and Ba0.7Sr0.3TiO3. The electronic properties investigated in this study were the dielectric constant and the voltage tunability. The morphology of the thin films were examined using the atomic force microscopy. Fourier transform Raman spectroscopy was also utilized for optical characterization of the thin films. The electronic and optical properties of the thin films and the bulk ceramics were compared. The results of these investigations are discussed.

  17. Novel p-Type Conductive Semiconductor Nanocrystalline Film as the Back Electrode for High-Performance Thin Film Solar Cells.

    Science.gov (United States)

    Zhang, Ming-Jian; Lin, Qinxian; Yang, Xiaoyang; Mei, Zongwei; Liang, Jun; Lin, Yuan; Pan, Feng

    2016-02-10

    Thin film solar cells, due to the low cost, high efficiency, long-term stability, and consumer applications, have been widely applied for harvesting green energy. All of these thin film solar cells generally adopt various metal thin films as the back electrode, like Mo, Au, Ni, Ag, Al, graphite, and so forth. When they contact with p-type layer, it always produces a Schottky contact with a high contact potential barrier, which greatly affects the cell performance. In this work, we report for the first time to find an appropriate p-type conductive semiconductor film, digenite Cu9S5 nanocrystalline film, as the back electrode for CdTe solar cells as the model device. Its low sheet resistance (16.6 Ω/sq) could compare to that of the commercial TCO films (6-30 Ω/sq), like FTO, ITO, and AZO. Different from the traditonal metal back electrode, it produces a successive gradient-doping region by the controllable Cu diffusion, which greatly reduces the contact potential barrier. Remarkably, it achieved a comparable power conversion efficiency (PCE, 11.3%) with the traditional metal back electrode (Cu/Au thin films, 11.4%) in CdTe cells and a higher PCE (13.8%) with the help of the Au assistant film. We believe it could also act as the back electrode for other thin film solar cells (α-Si, CuInS2, CIGSe, CZTS, etc.), for their performance improvement.

  18. Photoluminescence Study of Copper Selenide Thin Films

    Science.gov (United States)

    Urmila, K. S.; Asokan, T. Namitha; Pradeep, B.

    2011-10-01

    Thin films of Copper Selenide of composition of composition Cu7Se4 with thickness 350 nm are deposited on glass substrate at a temperature of 498 K±5 K and pressure of 10-5 mbar using reactive evaporation, a variant of Gunther's three temperature method with high purity Copper (99.999%) and Selenium (99.99%) as the elemental starting material. The deposited film is characterized structurally using X-ray Diffraction. The structural parameters such as lattice constant, particle size, dislocation density; number of crystallites per unit area and strain in the film are evaluated. Photoluminescence of the film is analyzed at room temperature using Fluoro Max-3 Spectrofluorometer.

  19. A facile strategy to synthesize bimetallic Au/Ag nanocomposite film by layer-by-layer assembly technique

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Li, E-mail: zhlisuzh@163.com [Anhui Key Laboratory of Spin Electron and Nanomaterials (Cultivating Base), Suzhou University, Suzhou 234000 (China); Wang Cong; Zhang Yi [Anhui Key Laboratory of Spin Electron and Nanomaterials (Cultivating Base), Suzhou University, Suzhou 234000 (China)

    2012-05-01

    A facile strategy has been developed for the preparation of bimetallic gold-silver (Au-Ag) nanocomposite films by alternating absorption of poly-(ethyleneimine)-silver ions and Au onto substrates and subsequent reduction of the silver ions. The composition, micro-structure and properties of the {l_brace}PEI-Ag/Au{r_brace}{sub n} nanocomposite films were characterized by ultraviolet visible spectroscopy (UV-vis), transmisson electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), surface enhanced Raman scattering (SERS) and cyclic voltammetry (CV). The UV-vis characteristic absorbances of {l_brace}PEI-Ag/Au{r_brace}{sub n} nanocomposite thin film increase almost linear with the number of bilayers, which indicates a process of uniform assembling. Appearance of a double plasmon bands in the visible region and the lack of apparent core-shell structures in the TEM images confirm the formation of bimetallic Au-Ag nanoparticles. The result of XPS also demonstrates the existence of Ag and Au nanoparticles in the nanocomposite films. TEM and FESEM images show that these Ag and Au nanoparticles in the films possess sphere structure with the size of 20-25 nm. The resulting {l_brace}PEI-Ag/Au{r_brace}{sub n} films inherit the properties from both the metal Ag and Au, which exhibits a unique performance in SERS and electrocatalytic activities to the oxidation of dopamine. As a result, the {l_brace}PEI-Ag/Au{r_brace}{sub n} films are more attractive compared to {l_brace}PEI-Ag/PSS{r_brace}{sub n} and {l_brace}PEI/Au{r_brace}{sub n} films.

  20. Preparation of organic thin-film field effect transistor

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The organic thin-film field effect transistor was prepared through vacuum deposition by using teflon as di-electric material. Indium-tin-oxide acted as the source and drain electrodes. Copper phthalocyanine and teflon were used as the semiconductor layer and dielectric layer, respectively. The gate electrode was made of Ag. The channel length between the source and drain was 50 μm. After preparing the source and drain electrodes by lithography, the copper phthalocyanine layer, teflon layer and Ag layerwere prepared by vacuum deposition sequentially. The field effect electron mobility of the device reached 1.1×10ˉ6 cm2/(V@s), and the on/off current ratio reached 500.

  1. Organic thin films and surfaces directions for the nineties

    CERN Document Server

    Ulman, Abraham

    1995-01-01

    Physics of Thin Films has been one of the longest running continuing series in thin film science consisting of 20 volumes since 1963. The series contains some of the highest quality studies of the properties ofvarious thin films materials and systems.In order to be able to reflect the development of todays science and to cover all modern aspects of thin films, the series, beginning with Volume 20, will move beyond the basic physics of thin films. It will address the most important aspects of both inorganic and organic thin films, in both their theoretical as well as technological aspects. Ther

  2. Thin film calorimetry of polymer films

    Science.gov (United States)

    Zhang, Wenhua; Rafailovich, Miriam; Sokolov, Jonathan; Salamon, William

    2000-03-01

    Polystryene and polymethylmethacrylate films for thicknesses ranging from 50nm to 500nm using a direct calorimetric technique (Lai et al, App. Phys. Lett. 67, p9(1995)). Samples were deposited on Ni foils(2-2.5um) and placed in a high vacuum oven. Calibrated heat pulses were input to the polymer films by current pulses to the Ni substrate and temperature changes were determined from the change in Ni resistance. Pulses producing temperature jumps of 3-8K were used and signal averaging over pulses reduced noise levels enough to identify glass transitions down to 50nm. Molecular weight dependence of thick films Tg was used as a temperature calibration.

  3. Investigating Quantum Oscillations in the Thermal Coefficient of Resistivity of Ultra-thin Ag Capping Layers on Cu for IC Interconnect Applications

    Science.gov (United States)

    Tatem, Elroy

    As the semiconductor industry continues to scale feature sizes, scattering from phonons, surfaces, and grain boundaries result in an increase of metal interconnect resistivity in state-of-the-art integrated circuits (ICs). The interconnect chapter of the 2011 International Technology Roadmap for Semiconductors (ITRS) stated that there are currently no manufacturable solutions in the near term for suitable Cu replacements. Previous studies of thin Ag films deposited on Cu demonstrated oscillations in the electron-phonon interactions within the bilayer system. This thesis investigates oscillations in the resistive properties of the Ag/Cu bilayer system and discusses the applicability of these oscillations to the resistivity challenges facing metal-based IC interconnects. Ag/Cu bilayer films were prepared by physical vapor deposition (PVD). The films were characterized by measuring the electrical resistance of the films at various temperatures and calculating the thermal coefficient of resistance (TCR) for various Ag capping layer thicknesses. Films were further characterized by atomic force microscopy (AFM), Rutherford backscattering (RBS), and scanning electron microscopy (SEM). Patterned Ag-capped Cu lines were fabricated, which exhibited resistive behavior similar to that of the Ag/Cu films. Compared to bare Cu, the resistances of Ag-capped Cu lines and films were lower and exhibited a reduced dependence on temperature. Smaller thermal coefficients of resistivity were also observed for Ag-capped Cu films and patterned lines when compared to Cu alone.

  4. Surface plasmon enhanced photoluminescence in amorphous silicon carbide films by adjusting Ag island film sizes

    Institute of Scientific and Technical Information of China (English)

    Yu Wei; Wang Xin-Zhan; Dai Wan-Lei; Lu Wan-Bing; Liu Yu-Mei; Fu Guang-Sheng

    2013-01-01

    Ag island films with different sizes are deposited on hydrogenated amorphous silicon carbide (α-SiC∶H) films,and the influences of Ag island films on the optical properties of the α-SiC∶H films are investigated.Atomic force microscope images show that Ag nanoislands are formed after Ag coating,and the size of the Ag islands increases with increasing Ag deposition time.The extinction spectra indicate that two resonance absorption peaks which correspond to out-of-plane and in-plane surface plasmon modes of the Ag island films are obtained,and the resonance peak shifts toward longer wavelength with increasing Ag island size.The photoluminescence (PL) enhancement or quenching depends on the size of Ag islands,and PL enhancement by 1.6 times on the main PL band is obtained when the sputtering time is 10 min.Analyses show that the influence of surface plasmons on the PL of α-SiC:H is determined by the competition between the scattering and absorption of Ag islands,and PL enhancement is obtained when scattering is the main interaction between the Ag islands and incident light.

  5. Vibration welding system with thin film sensor

    Science.gov (United States)

    Cai, Wayne W; Abell, Jeffrey A; Li, Xiaochun; Choi, Hongseok; Zhao, Jingzhou

    2014-03-18

    A vibration welding system includes an anvil, a welding horn, a thin film sensor, and a process controller. The anvil and horn include working surfaces that contact a work piece during the welding process. The sensor measures a control value at the working surface. The measured control value is transmitted to the controller, which controls the system in part using the measured control value. The thin film sensor may include a plurality of thermopiles and thermocouples which collectively measure temperature and heat flux at the working surface. A method includes providing a welder device with a slot adjacent to a working surface of the welder device, inserting the thin film sensor into the slot, and using the sensor to measure a control value at the working surface. A process controller then controls the vibration welding system in part using the measured control value.

  6. Nanostructured thin films and coatings mechanical properties

    CERN Document Server

    2010-01-01

    The first volume in "The Handbook of Nanostructured Thin Films and Coatings" set, this book concentrates on the mechanical properties, such as hardness, toughness, and adhesion, of thin films and coatings. It discusses processing, properties, and performance and provides a detailed analysis of theories and size effects. The book presents the fundamentals of hard and superhard nanocomposites and heterostructures, assesses fracture toughness and interfacial adhesion strength of thin films and hard nanocomposite coatings, and covers the processing and mechanical properties of hybrid sol-gel-derived nanocomposite coatings. It also uses nanomechanics to optimize coatings for cutting tools and explores various other coatings, such as diamond, metal-containing amorphous carbon nanostructured, and transition metal nitride-based nanolayered multilayer coatings.

  7. Domains in Ferroic Crystals and Thin Films

    CERN Document Server

    Tagantsev, Alexander K; Fousek, Jan

    2010-01-01

    Domains in Ferroic Crystals and Thin Films presents experimental findings and theoretical understanding of ferroic (non-magnetic) domains developed during the past 60 years. It addresses the situation by looking specifically at bulk crystals and thin films, with a particular focus on recently-developed microelectronic applications and methods for observation of domains with techniques such as scanning force microscopy, polarized light microscopy, scanning optical microscopy, electron microscopy, and surface decorating techniques. Domains in Ferroic Crystals and Thin Films covers a large area of material properties and effects connected with static and dynamic properties of domains, which are extremely relevant to materials referred to as ferroics. In most solid state physics books, one large group of ferroics is customarily covered: those in which magnetic properties play a dominant role. Numerous books are specifically devoted to magnetic ferroics and cover a wide spectrum of magnetic domain phenomena. In co...

  8. Thin Film Photovoltaic/Thermal Solar Panels

    Institute of Scientific and Technical Information of China (English)

    David JOHNSTON

    2008-01-01

    A solar panel is described.in which thin films of semiconductor are deposited onto a metal substrate.The semiconductor-metal combination forms a thin film photovoltaic cell,and also acts as a reflector,absorber tandem, which acts as a solar selective surface,thus enhancing the solar thermal performance of the collector plate.The use of thin films reduces the distance heat is required to flow from the absorbing surface to the metal plate and heat exchange conduits.Computer modelling demonstrated that,by suitable choice of materials,photovohaic efficiency call be maintained,with thermal performance slishtly reduced,compared to that for thermal-only panels.By grading the absorber layer-to reduce the band gap in the lower region-the thermal performance can be improved,approaching that for a thermal-only solar panel.

  9. Multifractal characteristics of titanium nitride thin films

    Directory of Open Access Journals (Sweden)

    Ţălu Ştefan

    2015-09-01

    Full Text Available The study presents a multi-scale microstructural characterization of three-dimensional (3-D micro-textured surface of titanium nitride (TiN thin films prepared by reactive DC magnetron sputtering in correlation with substrate temperature variation. Topographical characterization of the surfaces, obtained by atomic force microscopy (AFM analysis, was realized by an innovative multifractal method which may be applied for AFM data. The surface micromorphology demonstrates that the multifractal geometry of TiN thin films can be characterized at nanometer scale by the generalized dimensions Dq and the singularity spectrum f(α. Furthermore, to improve the 3-D surface characterization according with ISO 25178-2:2012, the most relevant 3-D surface roughness parameters were calculated. To quantify the 3-D nanostructure surface of TiN thin films a multifractal approach was developed and validated, which can be used for the characterization of topographical changes due to the substrate temperature variation.

  10. Solid surfaces, interfaces and thin films

    CERN Document Server

    Lüth, Hans

    2015-01-01

    This book emphasises both experimental and theoretical aspects of surface, interface and thin-film physics. As in previous editions the preparation of surfaces and thin films, their atomic and morphological structure, their vibronic and electronic properties as well as fundamentals of adsorption are treated. Because of their importance in modern information technology and nanostructure research, particular emphasis is paid to electronic surface and interface states, semiconductor space charge layers and heterostructures. A special chapter of the book is devoted to collective phenomena at interfaces and in thin films such as superconductivity and magnetism. The latter topic includes the meanwhile important issues giant magnetoresistance and spin-transfer torque mechanism, both effects being of high interest in information technology. In this new edition, for the first time, the effect of spin-orbit coupling on surface states is treated. In this context the class of the recently detected topological insulators,...

  11. Solid Surfaces, Interfaces and Thin Films

    CERN Document Server

    Lüth, Hans

    2010-01-01

    This book emphasises both experimental and theoretical aspects of surface, interface and thin film physics. As in previous editions the preparation of surfaces and thin films, their atomic and morphological, their vibronic and electronic properties as well as fundamentals of adsorption are treated. Because of their importance in modern information technology and nanostructure physics particular emphasis is paid to electronic surface and interface states, semiconductor space charge layers and heterostructures as well as to superconductor/semiconductor interfaces and magnetic thin films. The latter topic was significantly extended in this new edition by more details about the giant magnetoresistance and a section about the spin-transfer torque mechanism including one new problem as exercise. Two new panels about Kerr-effect and spin-polarized scanning tunnelling microscopy were added, too. Furthermore, the meanwhile important group III-nitride surfaces and high-k oxide/semiconductor interfaces are shortly discu...

  12. A First Step Towards a Microfabricated Thin-Film Sensor Array on the Basis of Chalcogenide Glass Materials

    Directory of Open Access Journals (Sweden)

    Michael J. Schöning

    2002-09-01

    Full Text Available A first step towards a microfabricated potentiometric thin-film sensor array for the simultaneous detection of Pb2+, Cd2+ and Cu2+ has been realized. The sensitive layers used are on the basis of chalcogenide glass materials. These thin-film chalcogenide glass materials that consist of mixtures of Pb-Ag-As-I-S, Cd-Ag-As-I-S or Cu-Ag-As-Se have been prepared by pulsed laser deposition technique. The developed sensor array has been physically characterized by means of scanning electron microscopy and Rutherford backscattering spectrometry. The electrochemical sensor characterization has been performend by potentiometric measurements.

  13. Parameters controlling microstructures and resistance switching of electrodeposited cuprous oxide thin films

    Science.gov (United States)

    Yazdanparast, Sanaz

    2016-12-01

    Cuprous oxide (Cu2O) thin films were electrodeposited cathodically from a highly alkaline bath using tartrate as complexing agent. Different microstructures for Cu2O thin films were achieved by varying the applied potential from -0.285 to -0.395 V versus a reference electrode of Ag/AgCl at 50 °C in potentiostatic mode, and separately by changing the bath temperature from 25 to 50 °C in galvanostatic mode. Characterization experiments showed that both grain size and orientation of Cu2O can be controlled by changing the applied potential. Applying a high negative potential of -0.395 V resulted in smaller grain size of Cu2O thin films with a preferred orientation in [111] direction. An increase in the bath temperature in galvanostatic electrodeposition increased the grain size of Cu2O thin films. All the films in Au/Cu2O/Au-Pd cell showed unipolar resistance switching behavior after an initial FORMING process. Increasing the grain size of Cu2O thin films and decreasing the top electrode area increased the FORMING voltage and decreased the current level of high resistance state (HRS). The current in low resistance state (LRS) was independent of the top electrode area and the grain size of deposited films, suggesting a filamentary conduction mechanism in unipolar resistance switching of Cu2O.

  14. Magnetically actuated peel test for thin films

    Energy Technology Data Exchange (ETDEWEB)

    Ostrowicki, G.T.; Sitaraman, S.K., E-mail: suresh.sitaraman@me.gatech.edu

    2012-03-30

    Delamination along thin film interfaces is a prevalent failure mechanism in microelectronic, photonic, microelectromechanical systems, and other engineering applications. Current interfacial fracture test techniques specific to thin films are limited by either sophisticated mechanical fixturing, physical contact near the crack tip, or complicated stress fields. Moreover, these techniques are generally not suitable for investigating fatigue crack propagation under cyclical loading. Thus, a fixtureless and noncontact experimental test technique with potential for fatigue loading is proposed and implemented to study interfacial fracture toughness for thin film systems. The proposed test incorporates permanent magnets surface mounted onto micro-fabricated released thin film structures. An applied external magnetic field induces noncontact loading to initiate delamination along the interface between the thin film and underlying substrate. Characterization of the critical peel force and peel angle is accomplished through in situ deflection measurements, from which the fracture toughness can be inferred. The test method was used to obtain interfacial fracture strength of 0.8-1.9 J/m{sup 2} for 1.5-1.7 {mu}m electroplated copper on natively oxidized silicon substrates. - Highlights: Black-Right-Pointing-Pointer Non-contact magnetic actuation test for interfacial fracture characterization. Black-Right-Pointing-Pointer Applied load is determined through voltage applied to the driving electromagnet. Black-Right-Pointing-Pointer Displacement and delamination propagation is measured using an optical profiler. Black-Right-Pointing-Pointer Critical peel force and peel angle is measured for electroplated Cu thin-film on Si. Black-Right-Pointing-Pointer The measured interfacial fracture energy of Cu/Si interface is 0.8-1.9 J/m{sup 2}.

  15. Modifying the thermal conductivity of small molecule organic semiconductor thin films with metal nanoparticles.

    Science.gov (United States)

    Wang, Xinyu; Parrish, Kevin D; Malen, Jonathan A; Chan, Paddy K L

    2015-11-04

    Thermal properties of organic semiconductors play a significant role in the performance and lifetime of organic electronic devices, especially for scaled-up large area applications. Here we employ silver nanoparticles (Ag NPs) to modify the thermal conductivity of the small molecule organic semiconductor, dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DNTT). The differential 3-ω method was used to measure the thermal conductivity of Ag-DNTT hybrid thin films. We find that the thermal conductivity of pure DNTT thin films do not vary with the deposition temperature over a range spanning 24 °C to 80 °C. The thermal conductivity of the Ag-DNTT hybrid thin film initially decreases and then increases when the Ag volume fraction increases from 0% to 32%. By applying the effective medium approximation to fit the experimental results of thermal conductivity, the extracted thermal boundary resistance of the Ag-DNTT interface is 1.14 ± 0.98 × 10(-7) m(2)-K/W. Finite element simulations of thermal conductivity for realistic film morphologies show good agreement with experimental results and effective medium approximations.

  16. Capillary instabilities in thin films. I. Energetics

    Energy Technology Data Exchange (ETDEWEB)

    Srolovitz, D.J.; Safran, S.A.

    1986-07-01

    A stability theory is presented which describes the conditions under which thin films rupture. It is found that holes in the film will either grow or shrink, depending on whether their initial radius is larger or smaller than a critical value. If the holes grow large enough, they impinge to form islands; the size of which are determined by the surface energies. The formation of grooves where the grain boundary meets the free surface is a potential source of holes which can lead to film rupture. Equilibrium grain boundary groove depths are calculated for finite grain sizes. Comparison of groove depth and film thickness yields microstructural conditions for film rupture. In addition, pits which form at grain boundary vertices, where three grains meet, are another source of film instability.

  17. Tailoring electronic structure of polyazomethines thin films

    Directory of Open Access Journals (Sweden)

    J. Weszka

    2010-09-01

    Full Text Available Purpose: The aim of this work is to show how electronic properties of polyazomethine thin films deposited by chemical vapor deposition method (CVD can be tailored by manipulating technological parameters of pristine films preparation as well as modifying them while the as-prepared films put into iodine atmosphere.Design/methodology/approach: The recent achievements in the field of designing and preparation methods to be used while preparing polymer photovoltaic solar cells or optoelectronic devices.Findings: The method used allow for pure pristine polymer thin films to be prtepared without any unintentional doping taking place during prepoaration methods. This is a method based on polycondensation process, where polymer chain developing is running directly due to chemical reaction between molecules of bifunctional monomers. The method applied to prepare thin films of polyazomethines takes advantage of monomer transporting by mreans of neutral transport agent as pure argon is.Research limitations/implications: The main disadvantage of alternately conjugated polymers seems to be quite low mobility of charge carrier that is expected to be a consequence of their backbone being built up of sp2 hybridized carbon and nitrogen atoms. Varying technological conditions towards increasing reagents mass transport to the substrate is expected to give such polyazomethine thin films organization that phenylene rin stacking can result in special π electron systems rather than linear ones as it is the case.Originality/value: Our results supply with original possibilities which can be useful in ooking for good polymer materials for optoelectronic and photovoltaic applications. These results have been gained on polyazomethine thin films but their being isoelectronic counterpart to widely used poly p-phenylene vinylene may be very convenient to develop high efficiency polymer solar cells

  18. Magnetite thin films: A simulational approach

    Energy Technology Data Exchange (ETDEWEB)

    Mazo-Zuluaga, J. [Grupo de Estado Solido y Grupo de Instrumentacion Cientifica y Microelectronica, Universidad de Antioquia, A.A. 1226 Medellin (Colombia)]. E-mail: jomazo@fisica.udea.edu.co; Restrepo, J. [Grupo de Estado Solido y Grupo de Instrumentacion Cientifica y Microelectronica, Universidad de Antioquia, A.A. 1226 Medellin (Colombia)

    2006-10-01

    In the present work the study of the magnetic properties of magnetite thin films is addressed by means of the Monte Carlo method and the Ising model. We simulate LxLxd magnetite thin films (d being the film thickness and L the transversal linear dimension) with periodic boundary conditions along transversal directions and free boundary conditions along d direction. In our model, both the three-dimensional inverse spinel structure and the interactions scheme involving tetrahedral and octahedral sites have been considered in a realistic way. Results reveal a power-law dependence of the critical temperature with the film thickness accordingly by an exponent {nu}=0.81 and ruled out by finite-size scaling theory. Estimates for the critical exponents of the magnetization and the specific heat are finally presented and discussed.

  19. Thin Film Electrodes for Rare Event Detectors

    Science.gov (United States)

    Odgers, Kelly; Brown, Ethan; Lewis, Kim; Giordano, Mike; Freedberg, Jennifer

    2017-01-01

    In detectors for rare physics processes, such as neutrinoless double beta decay and dark matter, high sensitivity requires careful reduction of backgrounds due to radioimpurities in detector components. Ultra pure cylindrical resistors are being created through thin film depositions onto high purity substrates, such as quartz glass or sapphire. By using ultra clean materials and depositing very small quantities in the films, low radioactivity electrodes are produced. A new characterization process for cylindrical film resistors has been developed through analytic construction of an analogue to the Van Der Pauw technique commonly used for determining sheet resistance on a planar sample. This technique has been used to characterize high purity cylindrical resistors ranging from several ohms to several tera-ohms for applications in rare event detectors. The technique and results of cylindrical thin film resistor characterization will be presented.

  20. Environmentally stable sputter-deposited thin films

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, D.J.

    1978-03-01

    Accelerated corrosion data are presented for the titanium-silver and chrome-gold thin film metallization systems presently used at Sandia Laboratories. Improvements in corrosion, hence reliability, as a result of interposing a thin intermediate layer of either platinum or palladium are shown. Potentiometric measurements showing the alteration of corrosion potential with the use of palladium for the titanium-silver system are also presented.

  1. Schottky Junction Methane Sensors Using Electrochemically Grown Nanocrystalline-Nanoporous ZnO Thin Films

    Directory of Open Access Journals (Sweden)

    P. K. Basu

    2009-01-01

    Full Text Available Nanocrystalline-nanoporous ZnO thin films were prepared by an electrochemical anodization method, and the films were tested as methane sensors. It was found that Pd-Ag catalytic contacts showed better sensing performance compared to other noble metal contacts like Pt and Rh. The methane sensing temperature could be reduced to as low as 100∘C by sensitizing nanocrystalline ZnO thin films with Pd, deposited by chemical method. The sensing mechanism has been discussed briefly.

  2. Micro-sensor thin-film anemometer

    Science.gov (United States)

    Sheplak, Mark (Inventor); McGinley, Catherine B. (Inventor); Spina, Eric F. (Inventor); Stephens, Ralph M. (Inventor); Hopson, Jr., Purnell (Inventor); Cruz, Vincent B. (Inventor)

    1996-01-01

    A device for measuring turbulence in high-speed flows is provided which includes a micro-sensor thin-film probe. The probe is formed from a single crystal of aluminum oxide having a 14.degree. half-wedge shaped portion. The tip of the half-wedge is rounded and has a thin-film sensor attached along the stagnation line. The bottom surface of the half-wedge is tilted upward to relieve shock induced disturbances created by the curved tip of the half-wedge. The sensor is applied using a microphotolithography technique.

  3. Feasibility Study of Thin Film Thermocouple Piles

    Science.gov (United States)

    Sisk, R. C.

    2001-01-01

    Historically, thermopile detectors, generators, and refrigerators based on bulk materials have been used to measure temperature, generate power for spacecraft, and cool sensors for scientific investigations. New potential uses of small, low-power, thin film thermopiles are in the area of microelectromechanical systems since power requirements decrease as electrical and mechanical machines shrink in size. In this research activity, thin film thermopile devices are fabricated utilizing radio frequency sputter coating and photoresist lift-off techniques. Electrical characterizations are performed on two designs in order to investigate the feasibility of generating small amounts of power, utilizing any available waste heat as the energy source.

  4. Emittance Theory for Thin Film Selective Emitter

    Science.gov (United States)

    Chubb, Donald L.; Lowe, Roland A.; Good, Brian S.

    1994-01-01

    Thin films of high temperature garnet materials such as yttrium aluminum garnet (YAG) doped with rare earths are currently being investigated as selective emitters. This paper presents a radiative transfer analysis of the thin film emitter. From this analysis the emitter efficiency and power density are calculated. Results based on measured extinction coefficients for erbium-YAG and holmium-YAG are presented. These results indicated that emitter efficiencies of 50 percent and power densities of several watts/sq cm are attainable at moderate temperatures (less than 1750 K).

  5. Advances in thin-film solar cells

    CERN Document Server

    Dharmadasa, I M

    2012-01-01

    This book concentrates on the latest developments in our understanding of solid-state device physics. The material presented is mainly experimental and based on CdTe thin-film solar cells. It extends these new findings to CIGS thin-film solar cells and presents a new device design based on graded bandgap multilayer solar cells. This design has been experimentally tested using the well-researched GaAs/AlGaAs system and initial devices have shown impressive device parameters. These devices are capable of absorbing all radiation (UV, visible, and infra-red) within the solar spectrum and combines

  6. Electrical analysis of niobium oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Graça, M.P.F., E-mail: mpfg@ua.pt [I3N & Physics Department, Aveiro University, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Saraiva, M. [I3N & Physics Department, Aveiro University, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Freire, F.N.A. [Mechanics Engineering Department, Ceará Federal University, Fortaleza (Brazil); Valente, M.A.; Costa, L.C. [I3N & Physics Department, Aveiro University, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal)

    2015-06-30

    In this work, a series of niobium oxide thin films was deposited by reactive magnetron sputtering. The total pressure of Ar/O{sub 2} was kept constant at 1 Pa, while the O{sub 2} partial pressure was varied up to 0.2 Pa. The depositions were performed in a grounded and non-intentionally heated substrate, resulting in as-deposited amorphous thin films. Raman spectroscopy confirmed the absence of crystallinity. Dielectric measurements as a function of frequency (40 Hz–110 MHz) and temperature (100 K–360 K) were performed. The dielectric constant for the film samples with thickness (d) lower than 650 nm decreases with the decrease of d. The same behaviour was observed for the conductivity. These results show a dependence of the dielectric permittivity with the thin film thickness. The electrical behaviour was also related with the oxygen partial pressure, whose increment promotes an increase of the Nb{sub 2}O{sub 5} stoichiometry units. - Highlights: • Niobium oxide thin films were deposited by reactive magnetron sputtering. • XRD showed a phase change with the increase of the P(O{sub 2}). • Raman showed that increasing P(O{sub 2}), Nb{sub 2}O{sub 5} amorphous increases. • Conductivity tends to decrease with the increase of P(O{sub 2}). • Dielectric analysis indicates the inexistence of preferential grow direction.

  7. Ag/TiO2薄膜结构和光催化性能研究%Structure and Photocatalytic Activities of Ag/TiO2 Thin Films

    Institute of Scientific and Technical Information of China (English)

    何超; 于云; 周彩华; 胡行方

    2002-01-01

    采用溶胶-凝胶技术制备了Ag掺杂的TiO2薄膜.用XRD、氮吸附法、UV-VIS-NIR分光光度计以及XPS对Ag掺杂后TiO2薄膜结构的变化进行了分析;用分光光学法通过在紫外光照下分解亚甲基蓝的实验比较了TiO2薄膜与Ag/TiO2薄膜的光催化性能.结果发现,掺杂适量的Ag有助于TiO2薄膜光催化氧化性能的提高,原因在于:(1)Ag通过引入耗尽层提高了TiO2的电荷分离能力,并吸引空穴向薄膜表面移动,结果使薄膜表面空穴的浓度提高,薄膜光催化效率提高;(2)Ag减小了TiO2粒子的粒径,使TiO2禁带宽度增大,薄膜光催化氧化的能力提高;(3)Ag掺杂后,TiO2薄膜表面对-OH基和水的吸附增加,使光照后TiO2薄膜表面活性自由基-OH的浓度增加,空穴向薄膜所吸附物质的转移能力提高.

  8. Raman spectroscopy of In2 S3∶Ag thin films%Ag掺杂In2 S3薄膜的拉曼光谱研究

    Institute of Scientific and Technical Information of China (English)

    林斯乐; 马靖; 程树英

    2013-01-01

    利用拉曼光谱结合 XRD与 SEM测试对未掺杂与Ag掺杂的 In2 S3薄膜进行了分析研究。XRD测试结果确定了 In2 S3的物相,并表明掺杂后晶粒尺寸发生一定的变化;拉曼光谱研究表明,掺杂后232、272及300cm-13条拉曼谱线发生红移,这是由于掺杂后晶格膨胀引起的。结合部分拉曼谱线半高宽的展宽证实了掺杂后薄膜中存在间隙 Ag 原子;SEM的测试结果进一步证实Ag掺杂后In2 S3晶格存在膨胀,并说明了In2 S3薄膜的生长方式。%The characteristics of undoped and silver doped In2 S3 films were studied via Raman spectroscopy,X-ray diffraction and scanning electron microscope.The phase of In2 S3 films was identified by XRD which showed the change of grain size after silver doped.As the films doped with silver,the red shift of Raman bands (232, 272 and 300cm-1 )of In2 S3 films took place.The broadening of linewidths (FWHM)of some Raman bands in-dicated the exist of interstitial silver ions.The SEM pictures showed the growth pattern and the larger grain size of In2 S3∶Ag films.

  9. Structural, morphological, electrical, and optical properties of silver thin films of varying thickness deposited on cupric oxide

    Science.gov (United States)

    Hajakbari, Fatemeh; Shafieinejad, Farzaneh

    2016-03-01

    In this investigation, silver (Ag) films of varying thickness (25-100 nm) were grown on cupric oxide (CuO) on silicon and quartz. The CuO preparation was carried out by the thermal oxidation annealing of copper (Cu) thin films deposited by DC magnetron sputtering. The physical properties of the prepared films were studied by different techniques. Rutherford backscattering spectroscopy (RBS) analysis indicated that the Ag film thickness was about 25-100 nm. X-ray diffraction (XRD) results showed that by increasing Ag thickness, the film crystallinity was improved. Also, atomic force microscopy (AFM) and scanning electron microscopy (SEM) results demonstrated that the surface morphology and the grain size were affected by the Ag film thickness. Furthermore, the electrical resistivity of films determined by four-point probe measurements versus the Ag film thickness was discussed. A reduction in the optical band gap energy of CuO is observed from 1.51 to 1.42 eV with an increase in Ag film thickness to 40 nm in Ag/CuO films.

  10. Perovskite Thin Films via Atomic Layer Deposition

    KAUST Repository

    Sutherland, Brandon R.

    2014-10-30

    © 2014 Wiley-VCH Verlag GmbH & Co. KGaA. (Graph Presented) A new method to deposit perovskite thin films that benefit from the thickness control and conformality of atomic layer deposition (ALD) is detailed. A seed layer of ALD PbS is place-exchanged with PbI2 and subsequently CH3NH3PbI3 perovskite. These films show promising optical properties, with gain coefficients of 3200 ± 830 cm-1.

  11. Perovskite thin films via atomic layer deposition.

    Science.gov (United States)

    Sutherland, Brandon R; Hoogland, Sjoerd; Adachi, Michael M; Kanjanaboos, Pongsakorn; Wong, Chris T O; McDowell, Jeffrey J; Xu, Jixian; Voznyy, Oleksandr; Ning, Zhijun; Houtepen, Arjan J; Sargent, Edward H

    2015-01-01

    A new method to deposit perovskite thin films that benefit from the thickness control and conformality of atomic layer deposition (ALD) is detailed. A seed layer of ALD PbS is place-exchanged with PbI2 and subsequently CH3 NH3 PbI3 perovskite. These films show promising optical properties, with gain coefficients of 3200 ± 830 cm(-1) .

  12. Dielectric breakdown in nano-porous thin films

    Science.gov (United States)

    Borja, Juan Pablo

    Unknown to most computer users and mobile device enthusiasts, we have finally entered into a critical age of chip manufacturing. January of 2014 marks the official start of the quest by the semiconductor industry to successfully integrate sub 14nm process technology nodes in accordance to the International Technology Roadmap for Semiconductors (ITRS). The manufacturing of nano-scale features represents a major bottleneck of its own. However, a bigger challenge lies in reliably isolating the massive chip interconnect network. The present work is aimed at generating a theoretical and experimental framework to predict dielectric breakdown for thin films used in computer chip components. Here, a set of experimental techniques are presented to assess and study dielectric failure in novel thin films. A theory of dielectric breakdown in thin nano-porous films is proposed to describe combined intrinsic and metal ion catalyzed failure. This theory draws on experimental evidence as well as fundamental concepts from mass and electronic charge transport. The drift of metal species was found to accelerate intrinsic dielectric failure. The solubility of metals species such as Cu was found to range from 7.0x1025 ions/m3 to 1.86x1026 ions/m3 in 7% porous SiCOH films. The diffusion coefficient for Cu species was found to span from 4.2x10-19 m2/s to 1.86x10-21 m2/s. Ramped voltage stress experiments were used to identify intrinsic failure from metal catalyzed failure. Intrinsic breakdown is defined when time to failure against applied field ramp rate results in ∂(ln(TTF))/∂(ln(R)) ≈ -1. Intrinsic failure was studied using Au. Here, ∂(ln(TTF))/∂(ln(R)) ≈ -0.95, which is an experimental best case scenario for intrinsic failure. Au is commonly reluctant to ionize which means that failure occurs in the absence of ionic species. Metal catalyzed failure was investigated using reactive electrodes such as Cu, and Ag. Here, trends for ∂(ln(TTF))/∂(ln(R)) significantly

  13. 热处理对LiFe1-0.01xY0.005xAg0.005xPO4薄膜光波导传感元件气敏性的影响%Effect of Heat Treatment on LiFe1-0.01xY0.005xAg0.005xPO4 Thin Film Optical Waveguide's Gas Sensing Properties

    Institute of Scientific and Technical Information of China (English)

    帕提曼·尼扎木丁; 阿布力孜·伊米提; 米日古丽·依明; 帕提曼·亚森; 艾拜都拉·热合曼; 司马义·努尔拉

    2012-01-01

    以FeSO4·7H2O,H3PO4,LiOH·H2O,AgNO3及Y(NO3)3·6H2O为原料,利用水热法一步合成出了LiFe1 -0.01xY0.005xAg0.005PO4粉体(x=0.5,1.0),并将该材料作为敏感试剂,用旋转-甩涂法做成纳米薄膜固定在锡掺杂玻璃光波导表面,在不同温度下进行热处理.采用紫外-可见分光光度计、测厚仪以及自组装的玻璃光波导气敏测试仪研究了热处理对LiFe1-0.01xY0.005xAg0.005xPO4薄膜光学及气敏特性的影响.研究结果表明:在450℃下进行热处理的薄膜元件具有良好的光学透明及较好的气敏特性.相同浓度的不同挥发性有机气体中,该传感元件对二甲苯气体有很好的选择性响应,其检测响应范围为1×10-7~1×10-3(V/V),响应-恢复时间分别小于5和100s.%LiFe1 -0.01xY0.005xAg0.005PO4 ( x =0.5,1.0) was synthesized via hydrothermal method by one step using FeSO4·7H2O,H3PO4,LiOH·H2O,AgNO3 and Y(NO3)3·6H2O as precursors. LiFe1-0.01xY0.005xAg0.005xPO4 was selected as sensing materials and was subsequently utilized in a spin-coating procedure for the fabrication of LiFe1-0.01x Y0.005x Ag0.005xPO4 thin Elms,and then the coated film was dried at different temperatures. The effect of heat treatment on LiFe1-0.01xY0.005xAg0.005xPO4 thin film optical waveguide's gas sensing properties were studiedusing ultraviolet spectrophotometer,ellipsometer and self assembled optical waveguide gases testing apparatus. The experimental results indicated that the thin film sensing element,which was dried at 450℃,was exhibited good sensing capabilities and optical transparent. The sensor had higher response to the xylene gas than the other various volatile organic compounds at same concentration. These sensors exhibited good response to xylene gas in the range of 1×l0-7 to 1× 10-3 with response and recovery times less than 5 and 100 s.

  14. Workshop on thin film thermal conductivity measurements

    Science.gov (United States)

    Feldman, Albert; Balzaretti, Naira M.; Guenther, Arthur H.

    1998-04-01

    On a subject of considerable import to the laser-induced damage community, a two day workshop on the topic, Thin Film Thermal Conductivity Measurement was held as part of the 13th Symposium on Thermophysical Properties at the University of Colorado in Boulder CO, June 25 and 26, 1997. The Workshop consisted of 4 sessions of 17 oral presentations and two discussion sessions. Two related subjects of interest were covered; 1) methods and problems associated with measuring thermal conductivity ((kappa) ) of thin films, and 2) measuring and (kappa) of chemical vapor deposited (CVD) diamond. On the subject of thin film (kappa) measurement, several recently developed imaginative techniques were reviewed. However, several authors disagreed on how much (kappa) in a film differs from (kappa) in a bulk material of the same nominal composition. A subject of controversy was the definition of an interface. In the first discussion session, several questions were addressed, a principal one being, how do we know that the values of (kappa) we obtain are correct and is there a role for standards in thin film (kappa) measurement. The second discussion session was devoted to a round-robin interlaboratory comparison of (kappa) measurements on a set of CVD diamond specimens and several other specimens of lower thermal conductivity. Large interlaboratory differences obtained in an earlier round robin had been attributed to specimen inhomogeneity. Unfortunately, large differences were also observed in the second round robin even though the specimens were more homogenous. There was good consistency among the DC measurements, however, the AC measurements showed much greater variability. There was positive feedback from most of the attenders regarding the Workshop with nearly all respondents recommending another Workshop in three or fewer years. There was general recognition that thin film thermal conductivity measurements are important for predicting the resistance of optical coating

  15. YBCO thin films in ac and dc films

    CERN Document Server

    Shahzada, S

    2001-01-01

    We report studies on the dc magnetization of YBCO thin films in simultaneously applied dc and ac fields. The effect of the ac fields is to decrease the irreversible magnetization drastically leading to complete collapse of the hysteresis loops for relatively small ac fields (250e). The magnitude of the decrease depends on the component of the ac field parallel to the c-axis. The decrease is non-linear with ac amplitude and is explained in the framework of the critical state response of ultra thin films in perpendicular geometry. The ac fields increase the relaxation rapidly at short times while the long time response appears unaffected. (author)

  16. Pyroelectric coupling in thin film photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Karpov, Victor G.; Shvydka, Diana [Department of Physics and Astronomy, University of Toledo, OH (United States)

    2007-07-15

    We propose a theory of thin film photovoltaics in which one of the polycrystalline films is made of a pyroelectric material grains such as CdS. That film is shown to generate strong polarization improving the device open circuit voltage. Implications and supporting facts for the major photovoltaic types based on CdTe and CuIn(Ga)Se{sub 2} absorber layers are discussed. Band diagram of a pyroelectric (CdS) based PV junction. Arrows represent the charge carrier photo-generation. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  17. Study of iron mononitride thin films

    Energy Technology Data Exchange (ETDEWEB)

    Tayal, Akhil, E-mail: mgupta@csr.res.in; Gupta, Mukul, E-mail: mgupta@csr.res.in; Phase, D. M., E-mail: mgupta@csr.res.in; Reddy, V. R., E-mail: mgupta@csr.res.in; Gupta, Ajay, E-mail: mgupta@csr.res.in [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore,-452001 (India)

    2014-04-24

    In this work we have studied the crystal structural and local ordering of iron and nitrogen in iron mononitride thin films prepared using dc magnetron sputtering at sputtering power of 100W and 500W. The films were sputtered using pure nitrogen to enhance the reactivity of nitrogen with iron. The x-ray diffraction (XRD), conversion electron Mössbauer spectroscopy (CEMS) and soft x-ray absorption spectroscopy (SXAS) studies shows that the film crystallizes in ZnS-type crystal structure.

  18. Epitaxy of layered semiconductor thin films

    Science.gov (United States)

    Brahim Otsmane, L.; Emery, J. Y.; Jouanne, M.; Balkanski, M.

    1993-03-01

    Epilayers of InSe on InSe(00.1) and GaSe(00.1) have been grown by the molecular beam epitaxy (MBE) technique. Raman spectroscopy was used for a characterization of the structure and crystallinity in InSe/InSe(00.1) (homoepitaxy) and InSe/GaSe(00.1) (heteroepitaxy). The Raman spectra of the InSe thin films are identical to those of polytype γ-InSe. An activation of the E(LO) mode at 211 cm -1 is observed in these films here. Scanning electron microscopy (SEM) is also used to investigate surfaces of these films.

  19. Growth Induced Magnetic Anisotropy in Crystalline and Amorphous Thin Films

    Energy Technology Data Exchange (ETDEWEB)

    Hellman, Frances

    1998-10-03

    OAK B204 Growth Induced Magnetic Anisotropy in Crystalline and Amorphous Thin Films. The work in the past 6 months has involved three areas of magnetic thin films: (1) amorphous rare earth-transition metal alloys, (2) epitaxial Co-Pt and hTi-Pt alloy thin films, and (3) collaborative work on heat capacity measurements of magnetic thin films, including nanoparticles and CMR materials.

  20. Thin films for micro solid oxide fuel cells

    Science.gov (United States)

    Beckel, D.; Bieberle-Hütter, A.; Harvey, A.; Infortuna, A.; Muecke, U. P.; Prestat, M.; Rupp, J. L. M.; Gauckler, L. J.

    Thin film deposition as applied to micro solid oxide fuel cell (μSOFC) fabrication is an emerging and highly active field of research that is attracting greater attention. This paper reviews thin film (thickness ≤1 μm) deposition techniques and components relevant to SOFCs including current research on nanocrystalline thin film electrolyte and thin-film-based model electrodes. Calculations showing the geometric limits of μSOFCs and first results towards fabrication of μSOFCs are also discussed.

  1. Electrical Properties of Ag-Doped Ge2Sb2Te5 Films Used for Phase Change Random Access Memory

    Institute of Scientific and Technical Information of China (English)

    XIA Ji-Lin; LIU Bo; SONG Zhi-Tang; FENG Song-Lin; CHEN Bomy

    2005-01-01

    @@ Ag-doped Ge2Sb2 Te5 films were deposited by rf magnetron sputtering on SiO2/Si substrates.The content of Ag ranging from 4.5 to 11.3 at.% is determined by inductively coupled plasma atomic emission spectrometry.The crystallization temperature of Ag-doped Ge2Sb2 Te5 increases with the increasing Ag content and the stability of phase change film is improved greatly.Structures were measured by x-ray diffraction and the face-centered-cubic structure was more stable after Ag doping.Four-point probe was used to measure the sheet resistance of Agdoped Ge2Sb2 Te5 films annealed at different temperatures and it is indicated that Ag atoms increase the sheet resistance of Ge2Sb2 Te5 thin film when the annealing temperature is higher than about 360℃, which is beneficial for reducing the reset current.Current-voltage curves were tested and it is demonstrated that 4.5 at.% Ag doping into the Ge2Sb2Te5 film can reduce the threshold current from 1.46mA to 0.25mA and can only increase the threshold voltage slightly, which is very useful for low energy consumption.

  2. Photoelectrochemical water splitting on nanoporous GaN thin films for energy conversion under visible light

    Science.gov (United States)

    Cao, Dezhong; Xiao, Hongdi; Fang, Jiacheng; Liu, Jianqiang; Gao, Qingxue; Liu, Xiangdong; Ma, Jin

    2017-01-01

    Nanoporous (NP) GaN thin films, which were fabricated by an electrochemical etching method at different voltages, were used as photoelectrodes during photoelectrochemical (PEC) water splitting in 1 M oxalic acid solution. Upon illumination at a power density of 100 mW cm‑2 (AM 1.5), water splitting is observed in NP GaN thin films, presumably resulting from the valence band edge which is more positive than the redox potential of the oxidizing species. In comparison with NP GaN film fabricated at 8 V, NP GaN obtained at 18 V shows nearly twofold enhancement in photocurrent with the maximum photo-to-hydrogen conversion efficiency of 1.05% at ~0 V (versus Ag/AgCl). This enhancement could be explained with (i) the increase of surface area and surface states, and (ii) the decrease of resistances and carrier concentration in the NP GaN thin films. High stability of the NP GaN thin films during the PEC water splitting further confirms that the NP GaN thin film could be applied to the design of efficient solar cells and solar fuel devices.

  3. Luminescence Properties of Tb3+-Doped LuAG Films Prepared by Pechini Sol-Gel Method

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Lu3Al5O12 (LuAG) thin films with different Tb3+ concentration were prepared on carefully cleaned (111) silicon wafer by a Pechini process and dip-coating technique. Heat treatment was performed in the temperature range from 800 to 1100 ℃. The crystal structure was analyzed by XRD. The results show that LuAG film starts to crystallize at about 900 ℃, and the particle size increases with the sintering temperature. Excitation and emission spectra of Tb3+ doped LuAG films were measured. The effects of heat-treatment temperature and doping concentration of Tb3+ on the luminescent properties were also investigated. For a comparison study, Tb3+-doped LuAG powders were also prepared by the same sol-gel method.

  4. Correlated dewetting patterns in thin polystyrene films

    Energy Technology Data Exchange (ETDEWEB)

    Neto, Chiara [Department of Applied Physics, University of Ulm, Albert Einstein Allee 11, D-89069 Ulm (Germany); Jacobs, Karin [Department of Applied Physics, University of Ulm, Albert Einstein Allee 11, D-89069 Ulm (Germany); Seemann, Ralf [Department of Applied Physics, University of Ulm, Albert Einstein Allee 11, D-89069 Ulm (Germany); Blossey, Ralf [Centre for Bioinformatics, Saarland University, PO Box 151150, D-66041 Saarbruecken (Germany); Becker, Juergen [Institute of Applied Mathematics, University of Bonn, Beringstr. 6, D-53115 Bonn (Germany); Gruen, Guenther [Institute of Applied Mathematics, University of Bonn, Beringstr. 6, D-53115 Bonn (Germany)

    2003-01-15

    We describe preliminary results of experiments and simulations concerned with the dewetting of thin polystyrene films (thickness < 7 nm) on top of silicon oxide wafers. In the experiments we scratched an initially flat film with an atomic force microscopy (AFM) tip, producing dry channels in the film. Dewetting of the films was imaged in situ using AFM and a correlated pattern of holes ('satellite holes') was observed along the rims bordering the channels. The development of this complex film rupture process was simulated and the results of experiments and simulations are in good agreement. On the basis of these results, we attempt to explain the appearance of satellite holes and their positions relative to pre-existing holes.

  5. Correlated dewetting patterns in thin polystyrene films

    CERN Document Server

    Neto, C; Seemann, R; Blossey, R; Becker, J; Grün, G

    2003-01-01

    We describe preliminary results of experiments and simulations concerned with the dewetting of thin polystyrene films (thickness < 7 nm) on top of silicon oxide wafers. In the experiments we scratched an initially flat film with an atomic force microscopy (AFM) tip, producing dry channels in the film. Dewetting of the films was imaged in situ using AFM and a correlated pattern of holes ('satellite holes') was observed along the rims bordering the channels. The development of this complex film rupture process was simulated and the results of experiments and simulations are in good agreement. On the basis of these results, we attempt to explain the appearance of satellite holes and their positions relative to pre-existing holes.

  6. Humidity sensing characteristics of hydrotungstite thin films

    Indian Academy of Sciences (India)

    G V Kunte; S A Shivashankar; A M Umarji

    2008-11-01

    Thin films of the hydrated phase of tungsten oxide, hydrotungstite (H2WO4.H2O), have been grown on glass substrates using a dip-coating technique. The -axis oriented films have been characterized by X-ray diffraction and scanning electron microscopy. The electrical conductivity of the films is observed to vary with humidity and selectively show high sensitivity to moisture at room temperature. In order to understand the mechanism of sensing, the films were examined by X-ray diffraction at elevated temperatures and in controlled atmospheres. Based on these observations and on conductivity measurements, a novel sensing mechanism based on protonic conduction within the surface layers adsorbed onto the hydrotungstite film is proposed.

  7. Ternary compound thin film solar cells

    Science.gov (United States)

    Kazmerski, L. L.

    1975-01-01

    A group of ternary compound semiconductor (I-III-VI2) thin films for future applications in photovoltaic devices is proposed. The consideration of these materials (CuInSe2, CuInTe2 and especially CuInS2) for long range device development is emphasized. Much of the activity to date has been concerned with the growth and properties of CuInX2 films. X-ray and electron diffraction analyses, Hall mobility and coefficient, resistivity and carrier concentration variations with substrate and film temperature as well as grain size data have been determined. Both p- and n-type films of CuInS2 and CuInSe2 have been produced. Single and double source deposition techniques have been utilized. Some data have been recorded for annealed films.

  8. Stabilized thin film heterostructure for electrochemical applications

    DEFF Research Database (Denmark)

    2015-01-01

    The invention provides a method for the formation of a thin film multi-layered heterostructure upon a substrate, said method comprising the steps of: a. providing a substrate; b. depositing a buffer layer upon said substrate, said buffer layer being a layer of stable ionic conductor (B); c. depos...

  9. Bilaterally Microstructured Thin Polydimethylsiloxane Film Production

    DEFF Research Database (Denmark)

    Vudayagiri, Sindhu; Yu, Liyun; Hassouneh, Suzan Sager;

    2015-01-01

    Thin PDMS films with complex microstructures are used in the manufacturing of dielectric electro active polymer (DEAP) actuators, sensors and generators, to protect the metal electrode from large strains and to assure controlled actuation. The current manufacturing process at Danfoss Polypower A/...

  10. Bauschinger effect in unpassivated freestanding thin films

    NARCIS (Netherlands)

    Shishvan, S.S.; Nicola, L.; Van der Giessen, E.

    2010-01-01

    Two-dimensional (2D) discrete dislocation plasticity simulations are carried out to investigate the Bauschinger effect (BE) in freestanding thin films. The BE in plastic flow of polycrystalline materials is generally understood to be caused by inhomogeneous deformation during loading, leading to res

  11. Flexoelectricity in barium strontium titanate thin film

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Seol Ryung; Huang, Wenbin; Yuan, Fuh-Gwo; Jiang, Xiaoning, E-mail: xjiang5@ncsu.edu [Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Shu, Longlong [Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Electronic Materials Research Laboratory, International Center for Dielectric Research, Xi' an Jiao Tong University, Xi' an, Shaanxi 710049 (China); Maria, Jon-Paul [Department of Material Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2014-10-06

    Flexoelectricity, the linear coupling between the strain gradient and the induced electric polarization, has been intensively studied as an alternative to piezoelectricity. Especially, it is of interest to develop flexoelectric devices on micro/nano scales due to the inherent scaling effect of flexoelectric effect. Ba{sub 0.7}Sr{sub 0.3}TiO{sub 3} thin film with a thickness of 130 nm was fabricated on a silicon wafer using a RF magnetron sputtering process. The flexoelectric coefficients of the prepared thin films were determined experimentally. It was revealed that the thin films possessed a transverse flexoelectric coefficient of 24.5 μC/m at Curie temperature (∼28 °C) and 17.44 μC/m at 41 °C. The measured flexoelectric coefficients are comparable to that of bulk BST ceramics, which are reported to be 10–100 μC/m. This result suggests that the flexoelectric thin film structures can be effectively used for micro/nano-sensing devices.

  12. Amperometric Noise at Thin Film Band Electrodes

    DEFF Research Database (Denmark)

    Larsen, Simon T.; Heien, Michael L.; Taboryski, Rafael

    2012-01-01

    Background current noise is often a significant limitation when using constant-potential amperometry for biosensor application such as amperometric recordings of transmitter release from single cells through exocytosis. In this paper, we fabricated thin-film electrodes of gold and conductive...

  13. Recent progress in thin film organic photodiodes

    NARCIS (Netherlands)

    Inganäs, Olle; Roman, Lucimara S.; Zhang, Fengling; Johansson, D.M.; Andersson, M.R.; Hummelen, J.C.

    2001-01-01

    We review current developments in organic photodiodes, with special reference to multilayer thin film optics, and modeling of organic donor-acceptor photodiodes. We indicate possibilities to enhance light absorption in devices by nanopatterning as well as by blending, and also discuss materials scie

  14. Flexible thin-film NFC tags

    NARCIS (Netherlands)

    Myny, K.; Tripathi, A.K.; Steen, J.L. van der; Cobb, B.

    2015-01-01

    Thin-film transistor technologies have great potential to become the key technology for leafnode Internet of Things by utilizing the NFC protocol as a communication medium. The main requirements are manufacturability on flexible substrates at a low cost while maintaining good device performance char

  15. Welding Wires To Thin Thermocouple Films

    Science.gov (United States)

    Holanda, Raymond; Kim, Walter S.; Danzey, Gerald A.; Pencil, Eric; Wadel, Mary

    1993-01-01

    Parallel-gap resistance welding yields joints surviving temperatures of about 1,000 degrees C. Much faster than thermocompression bonding. Also exceeds conductive-paste bonding and sputtering thin films through porous flame-sprayed insulation on prewelded lead wires. Introduces no foreign material into thermocouple circuit and does not require careful control of thickness of flame-sprayed material.

  16. Quasifree Mg–H thin films

    NARCIS (Netherlands)

    Baldi, A.; Palmisano, V.; Gonzalez-Silveira, M.; Pivak, Y.; Slaman, M.; Schreuders, H.; Dam, B.; Griessen, R.

    2009-01-01

    The thermodynamics of hydrogen absorption in Pd-capped Mg films are strongly dependent on the magnesium thickness. In the present work, we suppress such dependency by inserting a thin Ti layer between Mg and Pd. By means of optical measurements, we show that the surface energy contribution to the de

  17. Tailored piezoelectric thin films for energy harvester

    NARCIS (Netherlands)

    Wan, X.

    2013-01-01

    Piezoelectric materials are excellent materials to transfer mechanical energy into electrical energy, which can be stored and used to power other devices. PiezoMEMS is a good way to combine silicon wafer processing and piezoelectric thin film technology and lead to a variety of miniaturized and prem

  18. Incipient plasticity in metallic thin films

    NARCIS (Netherlands)

    Soer, W. A.; De Hosson, J. Th. M.; Minor, A. M.; Shan, Z.; Asif, S. A. Syed; Warren, O. L.

    2007-01-01

    The authors have compared the incipient plastic behaviors of Al and Al-Mg thin films during indentation under load control and displacement control. In Al-Mg, solute pinning limits the ability of dislocations to propagate into the crystal and thus substantially affects the appearance of plastic inst

  19. Intelligent Processing of Ferroelectric Thin Films

    Science.gov (United States)

    1994-05-31

    unsatisfactory. To detect the electroopic effects of thin films deposited on opaque substrates a waveguide refractometry of category 3 was reported. An advantage...of the waveguide refractometry is its capability of resolving the change in ordinary index from the change in the extraordinary index. Some successes

  20. Polarization Fatigue in Ferroelectric Thin Films

    Institute of Scientific and Technical Information of China (English)

    王忆; K.H.WONG; 吴文彬

    2002-01-01

    The fatigue problem in ferroelectric thin films is investigated based on the switched charge per unit area versus switching cycles. The temperature, dielectric permittivity, voltage bias, frequency and defect valence dependent switching polarization properties are calculated quantitatively with an extended Dawber-Scott model. The results are in agreement with the recent experiments.

  1. Amorphous silicon for thin-film transistors

    NARCIS (Netherlands)

    Schropp, Rudolf Emmanuel Isidore

    1987-01-01

    Hydrogenated amorphous silicon (a-Si:H) has considerable potential as a semiconducting material for large-area photoelectric and photovoltaic applications. Moreover, a-Si:H thin-film transistors (TFT’s) are very well suited as switching devices in addressable liquid crystal display panels and addres

  2. Thin-Film Solid Oxide Fuel Cells

    Science.gov (United States)

    Chen, Xin; Wu, Nai-Juan; Ignatiev, Alex

    2009-01-01

    The development of thin-film solid oxide fuel cells (TFSOFCs) and a method of fabricating them have progressed to the prototype stage. This can result in the reduction of mass, volume, and the cost of materials for a given power level.

  3. Electrostatic Discharge Effects in Thin Film Transistors

    NARCIS (Netherlands)

    Golo, Natasa

    2002-01-01

    Although amorphous silicon thin film transistors (α-Si:H TFT’s) have a very low electron mobility and pronounced instabilities of their electrical characteristics, they are still very useful and they have found their place in the semiconductors industry, as they possess some very good properties: th

  4. 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.

  5. Surface roughness evolution of nanocomposite thin films

    NARCIS (Netherlands)

    Turkin, A; Pei, Y.T.; Shaha, K.P.; Chen, C.Q.; Vainchtein, David; Hosson, J.Th.M. De

    2009-01-01

    An analysis of dynamic roughening and smoothening mechanisms of thin films grown with pulsed-dc magnetron sputtering is presented. The roughness evolution has been described by a linear stochastic equation, which contains the second- and fourth-order gradient terms. Dynamic smoothening of the growin

  6. SELF-LUBRICATING THIN FILMS FOR TOOL STEELS

    Directory of Open Access Journals (Sweden)

    Peter Jurči

    2012-02-01

    Full Text Available Specimens made from Vanadis 6 cold work tool steel were machined, ground, heat processed by standard regime and finally mirror polished. After that, they were layered with CrAgN. The Ag-content in the layers was chosen to 3 wt% and 15 wt% respectively. Microstructural analysis revealed that the addition of 3 wt%Ag did not influence the growth manner of the films but the addition of 15 wt%Ag has made considerable changes in the film growth. The layer with 3 wt%Ag had excellent adhesion on the steel substrate. On the other hand, the addition of 15%Ag had strongly negative impact on the coating adhesion. Similar effect of different Ag addition has been established also to both the hardness and the Young modulus of the films, also. Both films have superior tribological properties against hard material (alumina as well as against soft counterpart (CuSn6 as-cast bronze.

  7. SELF-LUBRICATING THIN FILMS FOR TOOL STEELS

    Directory of Open Access Journals (Sweden)

    Peter Jurči

    2012-03-01

    Full Text Available Specimens made from Vanadis 6 cold work tool steel were machined, ground, heat processed by standard regime and finally mirror polished. After that, they were layered with CrAgN. The Ag-content in the layers was chosen to 3 wt% and 15 wt% respectively. Microstructural analysis revealed that the addition of 3 wt%Ag did not influence the growth manner of the films but the addition of 15 wt%Ag has made considerable changes in the film growth. The layer with 3 wt%Ag had excellent adhesion on the steel substrate. On the other hand, the addition of 15%Ag had strongly negative impact on the coating adhesion. Similar effect of different Ag addition has been established also to both the hardness and the Young modulus of the films, also. Both films have superior tribological properties against hard material (alumina as well as against soft counterpart (CuSn6 as-cast bronze.

  8. Practical design and production of optical thin films

    CERN Document Server

    Willey, Ronald R

    2002-01-01

    Fundamentals of Thin Film Optics and the Use of Graphical Methods in Thin Film Design Estimating What Can Be Done Before Designing Fourier Viewpoint of Optical Coatings Typical Equipment for Optical Coating Production Materials and Process Know-How Process Development Monitoring and Control of Thin Film Growth Appendix: Metallic and Semiconductor Material Graphs Author IndexSubject Index

  9. Nonlocal thin films in calculations of the Casimir force

    NARCIS (Netherlands)

    Esquivel-Sirvent, R.; Svetovoy, V.B.

    2005-01-01

    The Casimir force is calculated between plates with thin metallic coating. Thin films are described with spatially dispersive (nonlocal) dielectric functions. For thin films the nonlocal effects are more relevant than for half-spaces. However, it is shown that even for film thickness smaller than th

  10. Growth induced magnetic anisotropy in crystalline and amorphous thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hellman, F.

    1998-07-20

    The work in the past 6 months has involved three areas of magnetic thin films: (1) amorphous rare earth-transition metal alloys, (2) epitaxial Co-Pt and Ni-Pt alloy thin films, and (3) collaborative work on heat capacity measurements of magnetic thin films, including nanoparticles and CMR materials. A brief summary of work done in each area is given.

  11. Potentiostatic Deposition and Characterization of Cuprous Oxide Thin Films

    OpenAIRE

    2013-01-01

    Electrodeposition technique was employed to deposit cuprous oxide Cu2O thin films. In this work, Cu2O thin films have been grown on fluorine doped tin oxide (FTO) transparent conducting glass as a substrate by potentiostatic deposition of cupric acetate. The effect of deposition time on the morphologies, crystalline, and optical quality of Cu2O thin films was investigated.

  12. Monte Carlo simulation of magnetic nanostructured thin films

    Institute of Scientific and Technical Information of China (English)

    Guan Zhi-Qiang; Yutaka Abe; Jiang Dong-Hua; Lin Hai; Yoshitake Yamazakia; Wu Chen-Xu

    2004-01-01

    @@ Using Monte Carlo simulation, we have compared the magnetic properties between nanostructured thin films and two-dimensional crystalline solids. The dependence of nanostructured properties on the interaction between particles that constitute the nanostructured thin films is also studied. The result shows that the parameters in the interaction potential have an important effect on the properties of nanostructured thin films at the transition temperatures.

  13. Development of the α-IGZO/Ag/α-IGZO Triple-Layer Structure Films for the Application of Transparent Electrode

    Directory of Open Access Journals (Sweden)

    Kun-Neng Chen

    2017-02-01

    Full Text Available We investigated the structural, optical, and electrical properties of amorphous IGZO/silver/amorphous IGZO (α-IGZO/Ag/α-IGZO triple-layer structures that were deposited at room temperature on Eagle XG glass and flexible polyethylene terephthalate substrates through the sputtering method. Thin Ag layers with different thicknesses were inserted between two IGZO layers to form a triple-layer structure. Ag was used because of its lower absorption and resistivity. Field emission scanning electron microscopy measurements of the triple-layer structures revealed that the thicknesses of the Ag layers ranged from 13 to 41 nm. The thickness of the Ag layer had a large effect on the electrical and optical properties of the electrodes. The optimum thickness of the Ag metal thin film could be evaluated according to the optical transmittance, electrical conductivity, and figure of merit of the electrode. This study demonstrates that the α-IGZO/Ag/α-IGZO triple-layer transparent electrode can be fabricated with low sheet resistance (4.2 Ω/□ and high optical transmittance (88.1% at room temperature without postannealing processing on the deposited thin films.

  14. MISSE 5 Thin Films Space Exposure Experiment

    Science.gov (United States)

    Harvey, Gale A.; Kinard, William H.; Jones, James L.

    2007-01-01

    The Materials International Space Station Experiment (MISSE) is a set of space exposure experiments using the International Space Station (ISS) as the flight platform. MISSE 5 is a co-operative endeavor by NASA-LaRC, United Stated Naval Academy, Naval Center for Space Technology (NCST), NASA-GRC, NASA-MSFC, Boeing, AZ Technology, MURE, and Team Cooperative. The primary experiment is performance measurement and monitoring of high performance solar cells for U.S. Navy research and development. A secondary experiment is the telemetry of this data to ground stations. A third experiment is the measurement of low-Earth-orbit (LEO) low-Sun-exposure space effects on thin film materials. Thin films can provide extremely efficacious thermal control, designation, and propulsion functions in space to name a few applications. Solar ultraviolet radiation and atomic oxygen are major degradation mechanisms in LEO. This paper is an engineering report of the MISSE 5 thm films 13 months space exposure experiment.

  15. Thin-film semiconductor rectifier has improved properties

    Science.gov (United States)

    1966-01-01

    Cadmium selenide-zinc selenide film is used as a thin film semiconductor rectifier. The film is vapor-deposited in a controlled concentration gradient into a glass substrate to form the required junctions between vapor-deposited gold electrodes.

  16. Thin blend films of cellulose and polyacrylonitrile

    Science.gov (United States)

    Lu, Rui; Zhang, Xin; Mao, Yimin; Briber, Robert; Wang, Howard

    Cellulose is the most abundant renewable, biocompatible and biodegradable natural polymer. Cellulose exhibits excellent chemical and mechanical stability, which makes it useful for applications such as construction, filtration, bio-scaffolding and packaging. To further expand the potential applications of cellulose materials, their alloying with synthetic polymers has been investigated. In this study, thin films of cotton linter cellulose (CLC) and polyacrylonitrile (PAN) blends with various compositions spanning the entire range from neat CLC to neat PAN were spun cast on silicon wafers from common solutions in dimethyl sulfoxide / ionic liquid mixtures. The morphologies of thin films were characterized using optical microscopy, atomic force microscopy, scanning electron microscopy and X-ray reflectivity. Morphologies of as-cast films are highly sensitive to the film preparation conditions; they vary from featureless smooth films to self-organized ordered nano-patterns to hierarchical structures spanning over multiple length scales from nanometers to tens of microns. By selectively removing the PAN-rich phase, the structures of blend films were studied to gain insights in their very high stability in hot water, acid and salt solutions.

  17. Nanoindentation study of electrodeposited Ag thin coating: An inverse calculation of anisotropic elastic-plastic properties

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Guang; Sun, Xin; Wang, Yuxin; Tay, See Leng; Gao, Wei

    2017-01-01

    A new inverse method was proposed to calculate the anisotropic elastic-plastic properties (flow stress) of thin electrodeposited Ag coating utilizing nanoindentation tests, previously reported inverse method for isotropic materials and three-dimensional (3-D) finite element analyses (FEA). Indentation depth was ~4% of coating thickness (~10 μm) to avoid substrate effect and different indentation responses were observed in the longitudinal (L) and the transverse (T) directions. The estimated elastic-plastic properties were obtained in the newly developed inverse method by matching the predicted indentation responses in the L and T directions with experimental measurements considering indentation size effect (ISE). The results were validated with tensile flow curves measured from free-standing (FS) Ag film. The current method can be utilized to characterize the anisotropic elastic-plastic properties of coatings and to provide the constitutive properties for coating performance evaluations.

  18. Polyester fabric coated with Ag/ZnO composite film by magnetron sputtering

    Science.gov (United States)

    Yuan, Xiaohong; Xu, Wenzheng; Huang, Fenglin; Chen, Dongsheng; Wei, Qufu

    2016-12-01

    Ag/ZnO composite film was successfully deposited on polyester fabric by using direct current (DC) magnetron sputtering and radio frequency (RF) magnetron reaction sputtering techniques with pure silver (Ag) and zinc (Zn) targets. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were used to examine the deposited film on the fabric. It was found that the zinc film coated on Ag film before RF reactive sputtering could protect the silver film from oxidation. Anti-ultraviolet property and antistatic property of the coated samples using different magnetron sputtering methods were also investigated. The experimental results showed that Ag film was oxidized into in Ag2O film in high vacuum oxygen environment. The deposition of Zn film on the surface of the fabric coated with Ag film before RF reactive sputtering, could successfully obtained Ag/ZnO composite film, and also generated structural color on the polyester fabric.

  19. Thin film instability with thermal noise

    CERN Document Server

    Diez, Javier A; Fernández, Roberto

    2016-01-01

    We study the effects of stochastic thermal fluctuations on the instability of the free surface of a flat liquid film upon a solid substrate. These fluctuations are represented as a standard Brownian motion that can be added to the deterministic equation for the film thickness within the lubrication approximation. Here, we consider that while the noise term is white in time, it is coloured in space. This allows for the introduction of a finite correlation length in the description of the randomized intermolecular interaction. Together with the expected spatial periodicity of the flow, we find a dimensionless parameter, $\\beta$, that accounts for the relative importance of the spatial correlation. We perform here the linear stability analysis (LSA) of the film under the influence of both terms, and find the corresponding power spectra for the amplitudes of the normal modes of the instability. We compare this theoretical result with the numerical simulations of the complete non-linear problem, and find a good ag...

  20. Thin Film Electrochemical Power Cells

    Science.gov (United States)

    1991-01-01

    Anion Intercalating Polymer Cathode", proceedings of symposium on Lithium Batteries, The Electrochemical Society , Hollywood, Florida. K. Naoi, W.H...of symposium on Lithium Batteries, The Electrochemical Society , Hollywood, Florida. M. Lien and W.H. Smyrl, "An Impedance Study of Polyvinylferrocene...Films", in Transient Techniques in Corrosion Science and Engineering, eds. W.H. Smyrl, et al., Electrochemical Society , 1989. K, Naoi, M.M. Lien and

  1. Thin film bismuth iron oxides useful for piezoelectric devices

    Energy Technology Data Exchange (ETDEWEB)

    Zeches, Robert J.; Martin, Lane W.; Ramesh, Ramamoorthy

    2016-05-31

    The present invention provides for a composition comprising a thin film of BiFeO.sub.3 having a thickness ranging from 20 nm to 300 nm, a first electrode in contact with the BiFeO.sub.3 thin film, and a second electrode in contact with the BiFeO.sub.3 thin film; wherein the first and second electrodes are in electrical communication. The composition is free or essentially free of lead (Pb). The BFO thin film is has the piezoelectric property of changing its volume and/or shape when an electric field is applied to the BFO thin film.

  2. Electroanalysis of tetracycline using nickel-implanted boron-doped diamond thin film electrode applied to flow injection system.

    Science.gov (United States)

    Treetepvijit, Surudee; Chuanuwatanakul, Suchada; Einaga, Yasuaki; Sato, Rika; Chailapakult, Orawon

    2005-05-01

    The electrochemical analysis of tetracycline was investigated using nickel-implanted boron-doped diamond thin film electrode by cyclic voltammetry and amperometry with a flow injection system. Cyclic voltammetry was used to study the electrochemical oxidation of tetracycline. Comparison experiments were carried out using as-deposited boron-doped diamond thin film electrode (BDD). Nickel-implanted boron-doped diamond thin film electrode (Ni-DIA) provided well-resolved oxidation irreversible cyclic voltammograms. The current signals were higher than those obtained using the as-deposited BDD electrode. Results using nickel-implanted boron-doped diamond thin film electrode in flow injection system coupled with amperometric detection are presented. The optimum potential for tetracycline was 1.55 V versus Ag/AgCl. The linear range of 1.0 to 100 microM and the detection limit of 10 nM were obtained. In addition, the application for drug formulation was also investigated.

  3. Roll-to-roll slot-die coating of 400 mm wide, flexible, transparent Ag nanowire films for flexible touch screen panels

    Science.gov (United States)

    Kim, Dong-Ju; Shin, Hae-In; Ko, Eun-Hye; Kim, Ki-Hyun; Kim, Tae-Woong; Kim, Han-Ki

    2016-09-01

    We report fabrication of large area Ag nanowire (NW) film coated using a continuous roll-to-roll (RTR) slot die coater as a viable alternative to conventional ITO electrodes for cost-effective and large-area flexible touch screen panels (TSPs). By controlling the flow rate of shear-thinning Ag NW ink in the slot die, we fabricated Ag NW percolating network films with different sheet resistances (30–70 Ohm/square), optical transmittance values (89–90%), and haze (0.5–1%) percentages. Outer/inner bending, twisting, and rolling tests as well as dynamic fatigue tests demonstrated that the mechanical flexibility of the slot-die coated Ag NW films was superior to that of conventional ITO films. Using diamond-shape patterned Ag NW layer electrodes (50 Ohm/square, 90% optical transmittance), we fabricated 12-inch flexible film-film type and rigid glass-film-film type TSPs. Successful operation of flexible TSPs with Ag NW electrodes indicates that slot-die-coated large-area Ag NW films are promising low cost, high performance, and flexible transparent electrodes for cost-effective large-area flexible TSPs and can be substituted for ITO films, which have high sheet resistance and are brittle.

  4. Physical Vapor Deposition of Thin Films

    Science.gov (United States)

    Mahan, John E.

    2000-01-01

    A unified treatment of the theories, data, and technologies underlying physical vapor deposition methods With electronic, optical, and magnetic coating technologies increasingly dominating manufacturing in the high-tech industries, there is a growing need for expertise in physical vapor deposition of thin films. This important new work provides researchers and engineers in this field with the information they need to tackle thin film processes in the real world. Presenting a cohesive, thoroughly developed treatment of both fundamental and applied topics, Physical Vapor Deposition of Thin Films incorporates many critical results from across the literature as it imparts a working knowledge of a variety of present-day techniques. Numerous worked examples, extensive references, and more than 100 illustrations and photographs accompany coverage of: * Thermal evaporation, sputtering, and pulsed laser deposition techniques * Key theories and phenomena, including the kinetic theory of gases, adsorption and condensation, high-vacuum pumping dynamics, and sputtering discharges * Trends in sputter yield data and a new simplified collisional model of sputter yield for pure element targets * Quantitative models for film deposition rate, thickness profiles, and thermalization of the sputtered beam

  5. Polycrystalline thin film materials and devices

    Energy Technology Data Exchange (ETDEWEB)

    Baron, B.N.; Birkmire, R.W.; Phillips, J.E.; Shafarman, W.N.; Hegedus, S.S.; McCandless, B.E. (Delaware Univ., Newark, DE (United States). Inst. of Energy Conversion)

    1992-10-01

    Results of Phase II of a research program on polycrystalline thin film heterojunction solar cells are presented. Relations between processing, materials properties and device performance were studied. The analysis of these solar cells explains how minority carrier recombination at the interface and at grain boundaries can be reduced by doping of windows and absorber layers, such as in high efficiency CdTe and CuInSe{sub 2} based solar cells. The additional geometric dimension introduced by the polycrystallinity must be taken into consideration. The solar cells are limited by the diode current, caused by recombination in the space charge region. J-V characteristics of CuInSe{sub 2}/(CdZn)S cells were analyzed. Current-voltage and spectral response measurements were also made on high efficiency CdTe/CdS thin film solar cells prepared by vacuum evaporation. Cu-In bilayers were reacted with Se and H{sub 2}Se gas to form CuInSe{sub 2} films; the reaction pathways and the precursor were studied. Several approaches to fabrication of these thin film solar cells in a superstrate configuration were explored. A self-consistent picture of the effects of processing on the evolution of CdTe cells was developed.

  6. Energetic deposition of thin metal films

    CERN Document Server

    Al-Busaidy, M S K

    2001-01-01

    deposited films. The primary aim of this thesis was to study the physical effect of energetic deposition metal thin films. The secondary aim is to enhance the quality of the films produced to a desired quality. Grazing incidence X-ray reflectivity (GIXR) measurements from a high-energy synchrotron radiation source were carried out to study and characterise the samples. Optical Profilers Interferometery, Atomic Force Microscope (AFM), Auger electron spectroscopy (AES), Medium energy ion spectroscopy (MEIS), and the Electron microscope studies were the other main structural characterisation tools used. AI/Fe trilayers, as well as multilayers were deposited using a Nordico planar D.C. magnetron deposition system at different voltage biases and pressures. The films were calibrated and investigated. The relation between energetic deposition variation and structural properties was intensely researched. Energetic deposition refers to the method in which the deposited species possess higher kinetic energy and impact ...

  7. When are thin films of metals metallic?

    Science.gov (United States)

    Plummer, E. W.; Dowben, P. A.

    1993-04-01

    There is an increasing body of experimental information suggesting that very thin films of materials, normally considered to be metals, exhibit behavior characteristic of a nonmetal. In almost all cases, there is a nonmetal-to-metal transition as a function of film density or thickness, frequently accompanied by a structural transition. Amazingly, this behavior seems to occur for metal films on metal substrates, as well as for metals on semiconductors. The identification of this phenomena and the subsequent explanation has been slow in developing, due to the inability to directly measure the conductivity of a submonolayer film. This paper will discuss the evidence accumulated from variety of spectroscopic experimental techniques for three systems: a Mott-Hubbard transition, a Peierls-like distortion, and a Wilson transition.

  8. Cathodoluminescence degradation of PLD thin films

    Science.gov (United States)

    Swart, H. C.; Coetsee, E.; Terblans, J. J.; Ntwaeaborwa, O. M.; Nsimama, P. D.; Dejene, F. B.; Dolo, J. J.

    2010-12-01

    The cathodoluminescence (CL) intensities of Y2SiO5:Ce3+, Gd2O2S:Tb3+ and SrAl2O4:Eu2+,Dy3+ phosphor thin films that were grown by pulsed laser deposition (PLD) were investigated for possible application in low voltage field emission displays (FEDs) and other infrastructure applications. Several process parameters (background gas, laser fluence, base pressure, substrate temperature, etc.) were changed during the deposition of the thin films. Atomic force microscopy (AFM) was used to determine the surface roughness and particle size of the different films. The layers consist of agglomerated nanoparticle structures. Samples with good light emission were selected for the electron degradation studies. Auger electron spectroscopy (AES) and CL spectroscopy were used to monitor changes in the surface chemical composition and luminous efficiency of the thin films. AES and CL spectroscopy were done with 2 keV energy electrons. Measurements were done at 1×10-6 Torr oxygen pressure. The formation of different oxide layers during electron bombardment was confirmed with X-ray photoelectron spectroscopy (XPS). New non-luminescent layers that formed during electron bombardment were responsible for the degradation in light intensity. The adventitious C was removed from the surface in all three cases as volatile gas species, which is consistent with the electron stimulated surface chemical reaction (ESSCR) model. For Y2SiO5:Ce3+ a luminescent SiO2 layer formed during the electron bombardment. Gd2O3 and SrO thin films formed on the surfaces of Gd2O2S:Tb3+ and SrAl2O4:Eu2+,Dy3+, respectively, due to ESSCRs.

  9. Optical thin films and coatings from materials to applications

    CERN Document Server

    Flory, Francois

    2013-01-01

    Optical coatings, including mirrors, anti-reflection coatings, beam splitters, and filters, are an integral part of most modern optical systems. This book provides an overview of thin film materials, the properties, design and manufacture of optical coatings and their use across a variety of application areas.$bOptical coatings, including mirrors, anti-reflection coatings, beam splitters, and filters, are an integral part of most modern optical systems. Optical thin films and coatings provides an overview of thin film materials, the properties, design and manufacture of optical coatings and their use across a variety of application areas. Part one explores the design and manufacture of optical coatings. Part two highlights unconventional features of optical thin films including scattering properties of random structures in thin films, optical properties of thin film materials at short wavelengths, thermal properties and colour effects. Part three focusses on novel materials for optical thin films and coatings...

  10. Thin Films for Coating Nanomaterials

    Institute of Scientific and Technical Information of China (English)

    S.M.Mukhopadhyay; P.Joshi; R.V.Pulikollu

    2005-01-01

    For nano-structured solids (those with one or more dimensions in the 1-100 nm range), attempts of surface modification can pose significant and new challenges. In traditional materials, the surface coating could be several hundreds nanometers in thickness, or even microns and millimeters. In a nano-structured material, such as particle or nanofibers, the coating thickness has to be substantially smaller than the bulk dimensions (100 nm or less), yet be durable and effective. In this paper, some aspects of effective nanometer scale coatings have been discussed. These films have been deposited by a non-line of sight (plasma)techniques; and therefore, they are capable of modifying nanofibers, near net shape cellular foams, and other high porosity materials. Two types of coatings will be focused upon: (a) those that make the surface inert and (b) those designed to enhance surface reactivity and bonding. The former has been achieved by forming 1-2 nm layer of -CF2- (and/or CF3) groups on the surface, and the latter by creating a nanolayer of SiO2-type compound. Nucleation and growth studies of the plasma-generated film indicate that they start forming as 2-3 nm high islands that grow laterally, and eventually completely cover the surface with 2-3nm film. Contact angle measurements indicate that these nano-coatings are fully functional even before they have achieved complete coverage of 2-3 nm. They should therefore be applicable to nano-structural solids.This is corroborated by application of these films on vapor grown nanofibers of carbon, and on graphitic foams. Coated and uncoated materials are infiltrated with epoxy matrix to form composites and their microstructure, as well as mechanical behaviors are compared. The results show that the nano-oxide coating can significantly enhance bond formation between carbon and organic phases, thereby enhancing wettability,dispersion, and composite behavior. The fluorocarbon coating, as expected, reduces bond formation, and

  11. Deposition and characterization of CuInS2 thin films deposited over copper thin films

    Science.gov (United States)

    Thomas, Titu; Kumar, K. Rajeev; Kartha, C. Sudha; Vijayakumar, K. P.

    2015-06-01

    Simple, cost effective and versatile spray pyrolysis method is effectively combined with vacuum evaporation for the deposition of CuIns2 thin films for photovoltaic applications. In the present study In2s3 was spray deposited over vacuum evaporated Cu thin films and Cu was allowed to diffuse in to the In2S3 layer to form CuInS2. To analyse the dependence of precursor volume on the formation of CuInS2 films structural, electrical and morphological analzes are carried out. Successful deposition of CuInS2thin films with good crystallinity and morphology with considerably low resistivity is reported in this paper.

  12. Metal nanoparticles for thin film solar cells

    DEFF Research Database (Denmark)

    Gritti, Claudia

    Among the different renewable ways to produce energy, photovoltaic cells have a big potential and the research is now focusing on getting higher efficiency and at the same time saving the manufacturing costs improving the performance of thin film solar cells. The spectral distribution...... a change from ZEP resist to double layer of PMMA and always requires preliminary exposure dose-tests and final particular attention for lift-off step. EBL resulted to be more suitable for silver NPs, since the deposition of gold (on top of an adhesion thin titanium layer) leads to a variation and non...

  13. The effect of Ag layer on the structural and magnetic properties of (001)-oriented [C/CoPt/Ag]{sub 5} films

    Energy Technology Data Exchange (ETDEWEB)

    Xu Xiaohong [School of Chemistry and Materials Science, Shanxi Normal University, Linfen, 041004 (China)]. E-mail: xuxh@dns.sxnu.edu.cn; Jin Tao [School of Chemistry and Materials Science, Shanxi Normal University, Linfen, 041004 (China); Li Xiaoli [School of Chemistry and Materials Science, Shanxi Normal University, Linfen, 041004 (China); Wang Fang [School of Chemistry and Materials Science, Shanxi Normal University, Linfen, 041004 (China); Jiang Fengxian [School of Chemistry and Materials Science, Shanxi Normal University, Linfen, 041004 (China); Wu Haishun [School of Chemistry and Materials Science, Shanxi Normal University, Linfen, 041004 (China)

    2007-02-26

    Ordered [C/CoPt/Ag]{sub 5} thin films with (001) preferred orientation have been deposited onto glass substrates by magnetron sputtering. The effects of the Ag layer on the structural and magnetic properties of the [C/CoPt/Ag]{sub 5} films were investigated. We have found that the presence of C sublayer together with the suitable thickness of Ag sublayer can provide a driving force for the chemical ordering of the L1{sub 0} CoPt phase, as well as give an opportunity for the (001)-oriented growth of CoPt grains. It was found that the structural and magnetic properties of CoPt films are strongly related to the strain arising from the misfit between Ag and CoPt layers as well as the C atom diffusion. These three element composite films with a high (001)-oriented growth, a strong perpendicular magnetic anisotropy, and a weak intergrain interactions can satisfy the requirements for ultra-high-density perpendicular recording medium.

  14. INVESTIGATION OF PHOTOELECTROCHROMIC THIN FILM AND DEVICE

    Institute of Scientific and Technical Information of China (English)

    M.J. Chen; H. Shen

    2005-01-01

    Photoelectrochromic device is a combination of dye-sensitized solar cells and electrochromic WO3 layers. Ectrochroelmic WO3 layer and TiO2 layer had been prepared by the sol-gel process, then be assembled to pohotoelectrochromic device. The effects of heating temperature on photoelectrochromic were investigated. The results showed that thin films prepared by dip-coating and spin-coating had good film quality and the device made by the method mentioned in the paper had good photoelectrochromie properties.

  15. Thermoviscoelastic models for polyethylene thin films

    DEFF Research Database (Denmark)

    Li, Jun; Kwok, Kawai; Pellegrino, Sergio

    2016-01-01

    This paper presents a constitutive thermoviscoelastic model for thin films of linear low-density polyethylene subject to strains up to yielding. The model is based on the free volume theory of nonlinear thermoviscoelasticity, extended to orthotropic membranes. An ingredient of the present approach...... is that the experimentally inaccessible out-of-plane material properties are determined by fitting the model predictions to the measured nonlinear behavior of the film. Creep tests, uniaxial tension tests, and biaxial bubble tests are used to determine the material parameters. The model has been validated experimentally...

  16. Thin film cadmium telluride solar cells

    Science.gov (United States)

    Chu, T. L.; Chu, Shirley S.; Ang, S. T.; Mantravadi, M. K.

    1987-08-01

    Thin-film p-CdTe/CdS/SnO2:F/glass solar cells of the inverted configuration were prepared by the deposition of p-type CdTe films onto CdS/SnO2:F/glass substrates using CVD or close-spaced sublimation (CSS) techniques based on the procedures of Chu et al. (1983) and Nicholl (1963), respectively. The deposition rates of p-CdTe films deposited by CSS were higher than those deposited by the CVD technique (4-5 min were sufficient), and the efficiencies higher than 10 percent were obtained. However, the resistivity of films prepared by CSS was not as readily controlled as that of the CVD films. The simplest technique to reduce the resistivity of the CSS p-CdTe films was to incorporate a dopant, such as As or Sb, into the reaction mixture during the preparation of the source material. The films with resistivities in the range of 500-1000 ohm cm were deposited in this manner.

  17. Electrochromism in copper oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, T.J.; Slack, J.L.; Rubin, M.D.

    2000-08-15

    Transparent thin films of copper(I) oxide prepared on conductive SnO2:F glass substrates by anodic oxidation of sputtered copper films or by direct electrodeposition of Cu2O transformed reversibly to opaque metallic copper films when reduced in alkaline electrolyte. In addition, the same Cu2O films transform reversibly to black copper(II) oxide when cycled at more anodic potentials. Copper oxide-to-copper switching covered a large dynamic range, from 85% and 10% photopic transmittance, with a coloration efficiency of about 32 cm2/C. Gradual deterioration of the switching range occurred over 20 to 100 cycles. This is tentatively ascribed to coarsening of the film and contact degradation caused by the 65% volume change on conversion of Cu to Cu2O. Switching between the two copper oxides (which have similar volumes) was more stable and more efficient (CE = 60 cm2/C), but covered a smaller transmittance range (60% to 44% T). Due to their large electrochemical storage capacity and tolerance for alkaline electrolytes, these cathodically coloring films may be useful as counter electrodes for anodically coloring electrode films such as nickel oxide or metal hydrides.

  18. 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.

  19. Polycrystalline thin films FY 1992 project report

    Energy Technology Data Exchange (ETDEWEB)

    Zweibel, K. [ed.

    1993-01-01

    This report summarizes the activities and results of the Polycrystalline Thin Film Project during FY 1992. The purpose of the DOE/NREL PV (photovoltaic) Program is to facilitate the development of PV that can be used on a large enough scale to produce a significant amount of energy in the US and worldwide. The PV technologies under the Polycrystalline Thin Film project are among the most exciting ``next-generation`` options for achieving this goal. Over the last 15 years, cell-level progress has been steady, with laboratory cell efficiencies reaching levels of 15 to 16%. This progress, combined with potentially inexpensive manufacturing methods, has attracted significant commercial interest from US and international companies. The NREL/DOE program is designed to support the efforts of US companies through cost-shared subcontracts (called ``government/industry partnerships``) that we manage and fund and through collaborative technology development work among industry, universities, and our laboratory.

  20. Polycrystalline thin films FY 1992 project report

    Energy Technology Data Exchange (ETDEWEB)

    Zweibel, K. (ed.)

    1993-01-01

    This report summarizes the activities and results of the Polycrystalline Thin Film Project during FY 1992. The purpose of the DOE/NREL PV (photovoltaic) Program is to facilitate the development of PV that can be used on a large enough scale to produce a significant amount of energy in the US and worldwide. The PV technologies under the Polycrystalline Thin Film project are among the most exciting next-generation'' options for achieving this goal. Over the last 15 years, cell-level progress has been steady, with laboratory cell efficiencies reaching levels of 15 to 16%. This progress, combined with potentially inexpensive manufacturing methods, has attracted significant commercial interest from US and international companies. The NREL/DOE program is designed to support the efforts of US companies through cost-shared subcontracts (called government/industry partnerships'') that we manage and fund and through collaborative technology development work among industry, universities, and our laboratory.

  1. EBSD analysis of electroplated magnetite thin films

    Science.gov (United States)

    Koblischka-Veneva, A.; Koblischka, M. R.; Teng, C. L.; Ryan, M. P.; Hartmann, U.; Mücklich, F.

    2010-05-01

    By means of electron backscatter diffraction (EBSD), we analyse the crystallographic orientation of electroplated magnetite thin films on Si/copper substrates. Varying the voltage during the electroplating procedure, the resulting surface properties are differing considerably. While a high voltage produces larger but individual grains on the surface, the surfaces become smoother on decreasing voltage. Good quality Kikuchi patterns could be obtained from all samples; even on individual grains, where the surface and the edges could be measured. The spatial resolution of the EBSD measurement could be increased to about 10 nm; thus enabling a detailed analysis of single magnetite grains. The thin film samples are polycrystalline and do not exhibit a preferred orientation. EBSD reveals that the grain size changes depending on the processing conditions, while the detected misorientation angles stay similar.

  2. Electrostatic Discharge Effects on Thin Film Resistors

    Science.gov (United States)

    Sampson, Michael J.; Hull, Scott M.

    1999-01-01

    Recently, open circuit failures of individual elements in thin film resistor networks have been attributed to electrostatic discharge (ESD) effects. This paper will discuss the investigation that came to this conclusion and subsequent experimentation intended to characterize design factors that affect the sensitivity of resistor elements to ESD. The ESD testing was performed using the standard human body model simulation. Some of the design elements to be evaluated were: trace width, trace length (and thus width to length ratio), specific resistivity of the trace (ohms per square) and resistance value. However, once the experiments were in progress, it was realized that the ESD sensitivity of most of the complex patterns under evaluation was determined by other design and process factors such as trace shape and termination pad spacing. This paper includes pictorial examples of representative ESD failure sites, and provides some options for designing thin film resistors that are ESD resistant. The risks of ESD damage are assessed and handling precautions suggested.

  3. Multiferroic oxide thin films and heterostructures

    Science.gov (United States)

    Lu, Chengliang; Hu, Weijin; Tian, Yufeng; Wu, Tom

    2015-06-01

    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.

  4. 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.

  5. Superconducting YBa 2Cu 3O 7- δ thin film grown on metallic film evaporated on MgO

    Science.gov (United States)

    Verdyan, A.; Azoulay, J.; Lapsker, I.

    2001-03-01

    At present it is commonly accepted that thin film formation of YBa 2Cu 3O 7- δ (YBCO) on conducting substrate is one of the keys to further development of advanced devices in the microelectronic and other applications. We have grown YBCO thin films by resistive evaporation technique on MgO coated with metallic layers (Ni or Ag). A simple inexpensive vacuum system equipped with resistively heated boats for metal and precursor mixture of yttrium, copper and barium fluoride powders was used. X-ray diffraction (XRD) and scanning electron microscopy techniques were used for texture, morphology and surface analyses respectively. Electrical and magnetical properties were determined by a standard dc four-probe method. The way of heating process is shown to be critical parameter in the film quality. The physical and electrical properties of the YBCO films are discussed in light of the fact that XRD measurements done on the metallic buffer layers have revealed a multicrystalline structure.

  6. Rechargeable thin-film lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Bates, J.B.; Gruzalski, G.R.; Dudney, N.J.; Luck, C.F.; Yu, Xiaohua

    1993-08-01

    Rechargeable thin-film batteries consisting of lithium metal anodes, an amorphous inorganic electrolyte, and cathodes of lithium intercalation compounds have recently been developed. The batteries, which are typically less than 6-{mu}m thick, can be fabricated to any specified size, large or small, onto a variety of substrates including ceramics, semiconductors, and plastics. The cells that have been investigated include Li-TiS{sub 2}, Li-V{sub 2}O{sub 5}, and Li-Li{sub x}Mn{sub 2}O{sub 4}, with open circuit voltages at full charge of about 2.5, 3.6, and 4.2, respectively. The development of these batteries would not have been possible without the discovery of a new thin-film lithium electrolyte, lithium phosphorus oxynitride, that is stable in contact with metallic lithium at these potentials. Deposited by rf magnetron sputtering of Li{sub 3}PO{sub 4} in N{sub 2}, this material has a typical composition of Li{sub 2.9}PO{sub 3.3}N{sub 0.46} and a conductivity at 25{degrees}C of 2 {mu}S/cm. The maximum practical current density obtained from the thin-film cells is limited to about 100 {mu}A/cm{sup 2} due to a low diffusivity of Li{sup +} ions in the cathodes. In this work, the authors present a short review of their work on rechargeable thin-film lithium batteries.

  7. Surface morphology of thin films polyoxadiazoles

    OpenAIRE

    J. Weszka; M.M. Szindler; M. Chwastek-Ogierman; BRUMA M.; P. Jarka; Tomiczek, B.

    2011-01-01

    urpose: The purpose of this paper was to analyse the surface morphology of thin films polyoxadiazoles. Design/methodology/approach: SSix different polymers which belong to the group of polyoxadiazoles were dissolved in the solvent NMP. Each of these polymer was deposited on a glass substrate and a spin coating method was applied with a spin speed of 1000, 2000 and 3000 rev/min. Changes in surface topography and roughness were observed. An atomic force microscope AFM Park System has been used....

  8. Quantized Nanocrystalline CdTe Thin Films

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Nanocrystalline CdTe thin films were prepared by asymmetric rectangular pulse electrodeposition in organic solution at 110°C. STM image shows a porous network morphology constructed by interconnected spherical CdTe crystallites with a mean diameter of 4.2 nm. A pronounced size quantization was indicated in the action and absorption spectra. Potentials dependence dual conductive behavior was revealed in the photocurrent-potential (I-V) curves.

  9. Incoherent and Laser Photodeposition on Thin Films.

    Science.gov (United States)

    1980-09-01

    mixing system. Both a carbon dioxide and dry chemical fire extinguisher were on hand in case a fire was initiated by the compounds. The dimethvlzinc was...summarizes three months of experimental effort devoted toward the production of thin films by the photodissociation of organometallic molecules containing the...that the threshold wavelength for the photodissociation of both Zn- 0 and Se- (CH3 )2 was approximately 2420A. Consequently, these laser photodeposition

  10. Design and characterization of thin film microcoolers

    Science.gov (United States)

    LaBounty, Chris; Shakouri, Ali; Bowers, John E.

    2001-04-01

    Thin film coolers can provide large cooling power densities compared to bulk thermoelectrics due to the close spacing of hot and cold junctions. Important parameters in the design of such coolers are investigated theoretically and experimentally. A three-dimensional (3D) finite element simulator (ANSYS) is used to model self-consistently thermal and electrical properties of a complete device structure. The dominant three-dimensional thermal and electrical spreading resistances acquired from the 3D simulation are also used in a one-dimensional model (MATLAB) to obtain faster, less rigorous results. Heat conduction, Joule heating, thermoelectric and thermionic cooling are included in these models as well as nonideal effects such as contact resistance, finite thermal resistance of the substrate and the heat sink, and heat generation in the wire bonds. Simulations exhibit good agreement with experimental results from InGaAsP-based thin film thermionic emission coolers which have demonstrated maximum cooling of 1.15 °C at room temperature. With the nonideal effects minimized, simulations predict that single stage thin film coolers can provide up to 20-30 °C degrees centigrade cooling with cooling power densities of several 1000 W/cm2.

  11. Indium sulfide thin films as window layer in chemically deposited solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Lugo-Loredo, S. [Universidad Autónoma de Nuevo León, UANL, Fac. de Ciencias Químicas, Av. Universidad S/N Ciudad Universitaria San Nicolás de Los Garza Nuevo León, C.P. 66451 (Mexico); Peña-Méndez, Y., E-mail: yolapm@gmail.com [Universidad Autónoma de Nuevo León, UANL, Fac. de Ciencias Químicas, Av. Universidad S/N Ciudad Universitaria San Nicolás de Los Garza Nuevo León, C.P. 66451 (Mexico); Calixto-Rodriguez, M. [Universidad Tecnológica Emiliano Zapata del Estado de Morelos, Av. Universidad Tecnológica No. 1, C.P. 62760 Emiliano Zapata, Morelos (Mexico); Messina-Fernández, S. [Universidad Autónoma de Nayarit, Ciudad de la Cultura “Amado Nervo” S/N, C.P. 63190 Tepic, Nayarit (Mexico); Alvarez-Gallegos, A. [Universidad Autónoma del Estado de Morelos, Centro de Investigación en Ingeniería y Ciencias Aplicadas, Av. Universidad 1001, C.P. 62209, Cuernavaca Morelos (Mexico); Vázquez-Dimas, A.; Hernández-García, T. [Universidad Autónoma de Nuevo León, UANL, Fac. de Ciencias Químicas, Av. Universidad S/N Ciudad Universitaria San Nicolás de Los Garza Nuevo León, C.P. 66451 (Mexico)

    2014-01-01

    Indium sulfide (In{sub 2}S{sub 3}) thin films have been synthesized by chemical bath deposition technique onto glass substrates using In(NO{sub 3}){sub 3} as indium precursor and thioacetamide as sulfur source. X-ray diffraction studies have shown that the crystalline state of the as-prepared and the annealed films is β-In{sub 2}S{sub 3}. Optical band gap values between 2.27 and 2.41 eV were obtained for these films. The In{sub 2}S{sub 3} thin films are photosensitive with an electrical conductivity value in the range of 10{sup −3}–10{sup −7} (Ω cm){sup −1}, depending on the film preparation conditions. We have demonstrated that the In{sub 2}S{sub 3} thin films obtained in this work are suitable candidates to be used as window layer in thin film solar cells. These films were integrated in SnO{sub 2}:F/In{sub 2}S{sub 3}/Sb{sub 2}S{sub 3}/PbS/C–Ag solar cell structures, which showed an open circuit voltage of 630 mV and a short circuit current density of 0.6 mA/cm{sup 2}. - Highlights: • In{sub 2}S{sub 3} thin films were deposited using the Chemical Bath Deposition technique. • A direct energy band gap between 2.41 to 2.27 eV was evaluated for the In{sub 2}S{sub 3} films. • We made chemically deposited solar cells using the In{sub 2}S{sub 3} thin films.

  12. Titanium diffusion in gold thin films

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, William E. [Materials Department, University of California, Santa Barbara, CA 93106-5050 (United States); Gregori, Giuliano, E-mail: g.gregori@fkf.mpg.d [California NanoSystems Institute, University of California, Santa Barbara, CA 93106-5050 (United States); Mates, Thomas [Materials Department, University of California, Santa Barbara, CA 93106-5050 (United States)

    2010-03-01

    In the present study, diffusion phenomena in titanium/gold (Ti/Au) thin films occurring at temperatures ranging between 200 and 400 {sup o}C are investigated. The motivation is twofold: the first objective is to characterize Ti diffusion into Au layer as an effect of different heat-treatments. The second goal is to prove that the implementation of a thin titanium nitride (TiN) layer between Ti and Au can remarkably reduce Ti diffusion. It is observed that Ti atoms can fully diffuse through polycrystalline Au thin films (260 nm thick) already at temperatures as a low as 250 {sup o}C. Starting from secondary ion mass spectroscopy data, the overall diffusion activation energy {Delta}E = 0.66 eV and the corresponding pre-exponential factor D{sub 0} = 5 x 10{sup -11} cm{sup 2}/s are determined. As for the grain boundary diffusivity, both the activation energy range 0.54 < {Delta}E{sub gb} < 0.66 eV and the pre-exponential factor s{sub 0}D{sub gb0} = 1.14 x 10{sup -8} cm{sup 2}/s are obtained. Finally, it is observed that the insertion of a thin TiN layer (40 nm) between gold and titanium acts as an effective diffusion barrier up to 400 {sup o}C.

  13. Preparation and properties of antimony thin film anode materials

    Institute of Scientific and Technical Information of China (English)

    SU Shufa; CAO Gaoshao; ZHAO Xinbing

    2004-01-01

    Metallic antimony thin films were deposited by magnetron sputtering and electrodeposition. Electrochemical properties of the thin film as anode materials for lithium-ion batteries were investigated and compared with those of antimony powder. It was found that both magnetron sputtering and electrodeposition are easily controllable processes to deposit antimony films with fiat charge/discharge potential plateaus. The electrochemical performances of antimony thin films, especially those prepared with magnetron sputtering, are better than those of antimony powder. The reversible capacities of the magnetron sputtered antimony thin film are above 400 mA h g-1 in the first 15 cycles.

  14. Analysis on superhydrophobic silver decorated copper Oxide nanostructured thin films for SERS studies.

    Science.gov (United States)

    Jayram, Naidu Dhanpal; Aishwarya, D; Sonia, S; Mangalaraj, D; Kumar, P Suresh; Rao, G Mohan

    2016-09-01

    The present work demonstrates the superhydrophobic and Surface Enhanced Raman Spectroscopy (SERS) active substrate performance of silver coated copper oxide (Ag@CuO) nanostructured thin films prepared by the SILAR process. Super hydrophobic substrates that combine super hydrophobic condensation effect and high enhancement ability of Ag@CuO nanoflowers are investigated for SERS studies. The possible growth mechanism for the formation of nanoflower arrays from nanospindles has been discussed. Morphology and crystallinity of the Ag@CuO thin films are confirmed using FESEM and XRD. The results obtained in the present study indicate that the as-deposited hydrophobic nanospindles structure converts to super hydrophobic nanoflower arrays on annealing at 200°C. The Ag@CuO super hydrophobic nanoflowers thin film based SERS substrates show highly enhanced Raman spectra with an EF value of 2.0×10(7) for (Rhodamine 6G) R6G, allowing a detection limit from a 10(-10)molL(-1) solution. The present study may provide a new perception in fabricating efficient super hydrophobic substrates for SERS, suggesting that the fabricated substrates are promising candidates for trace analysis of R6G dye and are expected to be widely used as highly sensitive SERS active substrates for various toxic dyes in the future.

  15. Control of nanoscale atomic arrangement in multicomponent thin films by temporally modulated vapour fluxes

    Science.gov (United States)

    Sarakinos, Kostas

    2016-09-01

    Synthesis of multicomponent thin films using vapor fluxes with a modulated deposition pattern is a potential route for accessing a wide gamut of atomic arrangements and morphologies for property tuning. In the current study, we present a research concept that allows for understanding the combined effect of flux modulation, kinetics and thermodynamics on the growth of multinary thin films. This concept entails the combined use of thin film synthesis by means of multiatomic vapor fluxes modulated with sub-monolayer resolution, deterministic growth simulations and nanoscale microstructure probes. Using this research concept we study structure formation within the archetype immiscible Ag-Cu binary system showing that atomic arrangement and morphology at different length scales is governed by diffusion of near-surface Ag atoms to encapsulate 3D Cu islands growing on 2D Ag layers. Moreover, we explore the relevance of the mechanism outlined above for morphology evolution and structure formation within the miscible Ag-Au binary system. The knowledge generated and the methodology presented herein provides the scientific foundation for tailoring atomic arrangement and physical properties in a wide range of miscible and immiscible multinary systems.

  16. Dynamic Characterization of Thin Film Magnetic Materials

    Science.gov (United States)

    Gu, Wei

    A broadband dynamic method for characterizing thin film magnetic material is presented. The method is designed to extract the permeability and linewidth of thin magnetic films from measuring the reflection coefficient (S11) of a house-made and short-circuited strip line testing fixture with or without samples loaded. An adaptive de-embedding method is applied to remove the parasitic noise of the housing. The measurements were carried out with frequency up to 10GHz and biasing magnetic fields up to 600 Gauss. Particular measurement setup and 3-step experimental procedures are described in detail. The complex permeability of a 330nm thick continuous FeGaB, 435nm thick laminated FeGaB film and a 100nm thick NiFe film will be induced dynamically in frequency-biasing magnetic field spectra and compared with a theoretical model based on Landau-Lifshitz-Gilbert (LLG) equations and eddy current theories. The ferromagnetic resonance (FMR) phenomenon can be observed among these three magnetic materials investigated in this thesis.

  17. Thin film cadmium telluride photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Compaan, A.; Bohn, R. (Toledo Univ., OH (United States))

    1992-04-01

    This report describes research to develop to vacuum-based growth techniques for CdTe thin-film solar cells: (1) laser-driven physical vapor deposition (LDPVD) and (2) radio-frequency (rf) sputtering. The LDPVD process was successfully used to deposit thin films of CdS, CdTe, and CdCl{sub 2}, as well as related alloys and doped semiconductor materials. The laser-driven deposition process readily permits the use of several target materials in the same vacuum chamber and, thus, complete solar cell structures were fabricated on SnO{sub 2}-coated glass using LDPVD. The rf sputtering process for film growth became operational, and progress was made in implementing it. Time was also devoted to enhancing or implementing a variety of film characterization systems and device testing facilities. A new system for transient spectroscopy on the ablation plume provided important new information on the physical mechanisms of LDPVD. The measurements show that, e.g., Cd is predominantly in the neutral atomic state in the plume but with a fraction that is highly excited internally ({ge} 6 eV), and that the typical neutral Cd translational kinetic energies perpendicular to the target are 20 eV and greater. 19 refs.

  18. 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.

  19. Sulfated cellulose thin films with antithrombin affinity

    Directory of Open Access Journals (Sweden)

    2009-11-01

    Full Text Available Cellulose thin films were chemically modified by in situ sulfation to produce surfaces with anticoagulant characteristics. Two celluloses differing in their degree of polymerization (DP: CEL I (DP 215–240 and CEL II (DP 1300–1400 were tethered to maleic anhydride copolymer (MA layers and subsequently exposed to SO3•NMe3 solutions at elevated temperature. The impact of the resulting sulfation on the physicochemical properties of the cellulose films was investigated with respect to film thickness, atomic composition, wettability and roughness. The sulfation was optimized to gain a maximal surface concentration of sulfate groups. The scavenging of antithrombin (AT by the surfaces was determined to conclude on their potential anticoagulant properties.

  20. Optical properties of thin polymer films

    Science.gov (United States)

    Kasarova, Stefka N.; Sultanova, Nina G.; Petrova, Tzveta; Dragostinova, Violeta; Nikolov, Ivan

    2009-10-01

    In this report three types of optical polymer thin films deposited on glass substrates are investigated. Transmission spectra of the polymer samples are obtained in the range from 400 nm to 1500 nm. A laser microrefractometer has been used to measure the refractive indices of the examined materials at 406, 656, 910 and 1320 nm. Dispersion properties of the polymer films are analyzed on the base of the Cauchy-Schott's and Sellmeier`s approximations. Dispersion coefficients are calculated and dispersion charts in the visible and near infrared spectral regions are presented and compared. Abbe numbers of mean and partial dispersion of the polymer films are obtained. Calculation of refractive indices at many laser emission wavelengths in the considered spectral range is accomplished.

  1. Inorganic and Organic Solution-Processed Thin Film Devices

    Institute of Scientific and Technical Information of China (English)

    Morteza Eslamian

    2017-01-01

    Thin films and thin film devices have a ubiquitous presence in numerous conventional and emerging tech-nologies. This is because of the recent advances in nanotechnology, the development of functional and smart materials, conducting polymers, molecular semiconductors, carbon nanotubes, and graphene, and the employment of unique prop-erties of thin films and ultrathin films, such as high surface area, controlled nanostructure for effective charge transfer, and special physical and chemical properties, to develop new thin film devices. This paper is therefore intended to provide a concise critical review and research directions on most thin film devices, including thin film transistors, data storage memory, solar cells, organic light-emitting diodes, thermoelectric devices, smart materials, sensors, and actuators. The thin film devices may consist of organic, inorganic, and composite thin layers, and share similar functionality, properties, and fabrication routes. Therefore, due to the multidisciplinary nature of thin film devices, knowledge and advances already made in one area may be applicable to other similar areas. Owing to the importance of developing low-cost, scalable, and vacuum-free fabrication routes, this paper focuses on thin film devices that may be processed and deposited from solution.

  2. Development of plasma assisted thermal vapor deposition technique for high-quality thin film

    Science.gov (United States)

    Lee, Kang-Il; Choi, Yong Sup; Park, Hyun Jae

    2016-12-01

    The novel technique of Plasma-Assisted Vapor Deposition (PAVD) is developed as a new deposition method for thin metal films. The PAVD technique yields a high-quality thin film without any heating of the substrate because evaporated particles acquire energy from plasma that is confined to the inside of the evaporation source. Experiments of silver thin film deposition have been carried out in conditions of pressure lower than 10-3 Pa. Pure silver plasma generation is verified by the measurement of the Ag-I peak using optical emission spectroscopy. A four point probe and a UV-VIS spectrophotometer are used to measure the electrical and optical properties of the silver film that is deposited by PAVD. For an ultra-thin silver film with a thickness of 6.5 nm, we obtain the result of high-performance silver film properties, including a sheet resistance 75%. The PAVD-film properties show a low sheet resistance of 30% and the same transmittance with conventional thermal evaporation film. In the PAVD source, highly energetic particles and UV from plasma do not reach the substrate because the plasma is completely shielded by the optimized nozzle of the crucible. This new PAVD technique could be a realistic solution to improve the qualities of transparent electrodes for organic light emission device fabrication without causing damage to the organic layers.

  3. Magnetic degradation of thin film multilayers during ion milling

    Directory of Open Access Journals (Sweden)

    J. C. Read

    2014-04-01

    Full Text Available We present a study of Ar ion milling-induced damage in exchange biased IrMn/CoFe/Ag-based magnetic multilayer thin films. While process variations determine the change in CoFe magnetic properties, the distance from the ion milling front to the IrMn/CoFe interface dominates the extent of exchange bias damage. Remarkably, the interfacial coupling energy Jk can be reduced by 50% before any removal of the CoFe pinned layer. We attribute the losses to microstructural changes and damage effects where cap material is driven into the CoFe layer below. Disturbance depth estimates from ion impact simulations agree reasonably with the observed length scales of damage.

  4. A New Method of Fabricating NASICON Thin Film

    Institute of Scientific and Technical Information of China (English)

    WNGLing; SUNJialin; 等

    1998-01-01

    Nasicon thin films of 15 μm thick on YSZ sub-strates were prepared by means of solid state reaction at 1230℃ for 10 hours,Stuctural characteriza-tion of the films were performed by XRD ,SEM and EDX,A new tyype of CO2 gas sensor with Nasicon thin film as solid electrolyte was developed.

  5. Bismuth thin films obtained by pulsed laser deposition

    Science.gov (United States)

    Flores, Teresa; Arronte, Miguel; Rodriguez, Eugenio; Ponce, Luis; Alonso, J. C.; Garcia, C.; Fernandez, M.; Haro, E.

    1999-07-01

    In the present work Bi thin films were obtained by Pulsed Laser Deposition, using Nd:YAG lasers. The films were characterized by optical microscopy. Raman spectroscopy and X-rays diffraction. It was accomplished the real time spectral emission characterization of the plasma generated during the laser evaporation process. Highly oriented thin films were obtained.

  6. Laser Direct Writing of Ag Films from Solution on Si Substrate

    Institute of Scientific and Technical Information of China (English)

    Ke SUN; Caibei ZHANG; Yan ZHAO

    2003-01-01

    Pulsed Nd:YAG laser was used to irradiate Si substrate immersed in AgNO3 ethylene glycol solution to deposit Ag films along the lines scanned by laser on the substrate, which is a photo-thermal decomposing process. The decomposed Ag atoms congregate and form polycrystalline Ag particles. The Ag concentration changes greatly with the total laser energy4absorbed by substrate. Transmission electron microscopy (TEM) observation shows the Ag particles are inlaid in the Si substrate. Auger electron spectrum (AES) shows that the Ag concentration decreases with the increase of the sputtering depth, and there is no oxygen element on the surface of the deposited Ag films.

  7. Microstructure and Raman spectra of Ag-MgF2 cermet films

    Institute of Scientific and Technical Information of China (English)

    Shouhua Shi(史守华); Zhuoliang Cao(曹卓良); Zhaoqi Sun(孙兆奇)

    2003-01-01

    Ag-MgF2 cermet films with different Ag fractions were prepared by vacuum evaporation. The microstruc-ture of the films was examined by Raman scattering technique. The surface-enhanced Raman spectrumfor MgF2 molecules in the cermet film strongly suggests the existence of Ag nanoparticles dispersed inMgF2 matrix. The intensities of the Raman spectra of Ag-MgF2 cermet films increase with Ag fraction.The enhancement of Raman scattering disappears when Ag content reaches wt.20%. The analyses withthe transmission electron microscopy showed that Ag-MgF2 cermet films are mainly composed of amor-phous MgF2 matrix with embedded faced-center-cubic Ag nanoparticles. It suggests that the percolationthreshold should be around wt.20% of Ag content.

  8. Improved Resistive Switching Characteristics of Ag-Doped ZrO2 Films Fabricated by Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    SUN Bing; LIU Li-Feng; HAN De-Dong; WANG Yi; LIU Xiao-Yan; HAN Ru-Qi; KANG Jin-Feng

    2008-01-01

    Ag-doped and pure ZrO2 thin films are prepared on Pt/Ti/SiO2/Si substrates by sol-gel process for resistive random access memory application. The highly reproducible resistive switching is achieved in the 10% Ag-doped ZrO2 devices. The improved resistive switching behaviour in the Ag doped ZrO2 devices could be attributed to Ag doping effect on the formation of the stable filamentary conducting paths. In addition, dual-step reset processes corresponding to three stable resistance states are observed in the 10% Ag doped ZrO2 devices, which may be implemented for the application of multi-bit storage.

  9. 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

  10. Characterization of AZO and Ag based films prepared by RF magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Dagang [Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hong Kong (China); Jiang, Shouxiang, E-mail: kinor.j@polyu.edu.hk [Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hong Kong (China); Zhao, Hongmei [Department of Prosthodontics, The Affiliated Hospital of Qingdao University, Qingdao (China); Shang, Songmin; Chen, Zhuoming [Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hong Kong (China)

    2014-12-15

    Highlights: • Highly infrared reflective AZO and Ag based films were prepared. • Ag showed better crystallization on AZO film than on glass substrate. • Infrared reflection rate was inversely proportional to the film sheet resistance. • Film with infrared reflection of 97% in FIR region was acquired. - Abstract: Ag, AZO/Ag, Ag/AZO and AZO/Ag/AZO films were prepared on glass substrates by radio frequency (RF) magnetron sputtering technology. The prepared films were systematically investigated by X-ray Diffraction (XRD), Atomic Force Microscopy (AFM), UV–visible spectrophotometer, a four-point probe system and Fourier Transform Infrared Spectroscopy. The results indicated that Ag inner layer starts forming a continuous film at the thickness of 10 nm and Ag layer presents superior crystallization on AZO substrate than that on glass substrate. The continuous Ag inner layer film provided the highest average visible transmittance of 85.4% (AZO/Ag/AZO). The lowest sheet resistance of 3.21 Ω/sq and the highest infrared reflection rate of 97% in FIR region can be obtained on AZO/Ag (15 nm)/AZO film. The high infrared reflection property of the AZO/Ag/AZO coating makes it a promising candidate for solar control films.

  11. Modification of magnetic anisotropy induced by swift heavy ion irradiation in cobalt ferrite thin films

    Energy Technology Data Exchange (ETDEWEB)

    Nongjai, Razia [Department of Applied Physics, Zakir Hussain College of Engineering & Technology, A.M.U., Aligarh 202002 (India); Khan, Shakeel, E-mail: skhanapad@gmail.com [Department of Applied Physics, Zakir Hussain College of Engineering & Technology, A.M.U., Aligarh 202002 (India); Ahmed, Hilal; Khan, Imran [Department of Applied Physics, Zakir Hussain College of Engineering & Technology, A.M.U., Aligarh 202002 (India); Annapoorni, S. [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Gautam, Sanjeev [Advanced Analysis Center, Korea Institute of Science and Technology (KIST), Seoul 136-791 (Korea, Republic of); Lin, Hong-Ji; Chang, Fan-Hsiu [National Synchrotron Radiation Research Center (NSRRC), Hsinchu 30076, Taiwan (China); Hwa Chae, Keun [Advanced Analysis Center, Korea Institute of Science and Technology (KIST), Seoul 136-791 (Korea, Republic of); Asokan, K. [Material Science Division, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India)

    2015-11-15

    The present study demonstrates the modification of magnetic anisotropy in cobalt ferrite (CoFe{sub 2}O{sub 4}) thin films induced by swift heavy ion irradiations of 200 MeV Ag-ion beams. The study reveals that both magnetizations and coercive field are sensitive to Ag-ions irradiation and to the fluences. The magnetic anisotropy enhanced at low fluence of Ag-ions due to domain wall pinning at defect sites created by ion bombardment and at high fluence, this magnetic anisotropy ceases and changes to isotropic behavior which is explained based on the significant structural and morphological changes. An X-ray absorption and x-ray magnetic circular dichroism studies confirms the inverse spinel structure of these compounds. - Highlights: • CoFe{sub 2}O{sub 4} thin films have been deposited on Silicon substrate by pulsed laser deposition technique. • Swift heavy ion irradiation of thin films at three different fluences. • Studied the structural and magnetic properties of the samples. • XRD and Raman studies indicate strain in the films. • Observed perpendicular magnetic anisotropy.

  12. Intrinsic instability of thin liquid films on nanostructured surfaces

    Science.gov (United States)

    Rokoni, Arif; Hu, Han; Sun, Liyong; Sun, Ying

    2016-11-01

    The instability of a thin liquid film on nanostructures is not well understood but is important in liquid-vapor two-phase heat transfer (e.g., thin film evaporation and boiling), lubrication, and nanomanufacturing. In thin film evaporation, the comparison between the non-evaporating film thickness and the critical film breakup thickness determines the stability of the film: the film becomes unstable when the critical film breakup thickness is larger than the non-evaporating film thickness. In this study, a closed-form model is developed to predict the critical breakup thickness of a thin liquid film on 2D periodic nanostructures based on minimization of system free energy in the limit of a liquid monolayer. Molecular dynamics simulations are performed for water thin films on square nanostructures of varying depth and wettability and the simulations agree with the model predictions. The results show that the critical film breakup thickness increases with the nanostructure depth and the surface wettability. The model developed here enables the prediction of the minimum film thickness for stable thin film evaporation on a given nanostructure.

  13. Cerium Dioxide Thin Films Using Spin Coating

    Directory of Open Access Journals (Sweden)

    D. Channei

    2013-01-01

    Full Text Available Cerium dioxide (CeO2 thin films with varying Ce concentrations (0.1 to 0.9 M, metal basis were deposited on soda-lime-silica glass substrates using spin coating. It was found that all films exhibited the cubic fluorite structure after annealing at 500°C for 5 h. The laser Raman microspectroscopy and GAXRD analyses revealed that increasing concentrations of Ce resulted in an increase in the degree of crystallinity. FIB and FESEM images confirmed the laser Raman and GAXRD analyses results owing to the predicted increase in film thickness with increasing Ce concentration. However, porosity and shrinkage (drying cracking of the films also increased significantly with increasing Ce concentrations. UV-VIS spectrophotometry data showed that the transmission of the films decreased with increasing Ce concentrations due to the increasing crack formation. Furthermore, a red shift was observed with increasing Ce concentrations, which resulted in a decrease in the optical indirect band gap.

  14. Electroless plating of thin gold films directly onto silicon nitride thin films and into micropores.

    Science.gov (United States)

    Whelan, Julie C; Karawdeniya, Buddini Iroshika; Bandara, Y M Nuwan D Y; Velleco, Brian D; Masterson, Caitlin M; Dwyer, Jason R

    2014-07-23

    A method to directly electrolessly plate silicon-rich silicon nitride with thin gold films was developed and characterized. Films with thicknesses plating free-standing ultrathin silicon nitride membranes, and we successfully plated the interior walls of micropore arrays in 200 nm thick silicon nitride membranes. The method is thus amenable to coating planar, curved, and line-of-sight-obscured silicon nitride surfaces.

  15. Evidence for improvement of critical current by Ag in YBaCuO-Ag thick films

    Science.gov (United States)

    Dwir, B.; Kellett, B.; Mieville, L.; Pavuna, D.

    1991-04-01

    The evidence is reported for enhancement of critical current density J(c) in YBa2Cu3O(7-delta) thick films with the addition of Ag, which is correlated with improvements in structural properties. An improvement of 50 percent in J(c) (up to about 500 A/sq cm at T = 4.2 K) was obtained in films made from YBCO + 60 wt pct Ag powder, fabricated by the spin-on technique on (100) SrTiO3, which is correlated with improvements in structure. The resulting films are 10 microns thick, uniform, partially textured, and show good adherence. The critical temperature Tc is improved by the addition of Ag, and a reduction in the density of microcracks and in the amount of secondary phases in the sintered films was observed. Normal-state resistivity is reduced by almost three orders of magnitude, making these films potentially useful for electronic applications in interconnects and novel hybrid circuits.

  16. Evidence for improvement of critical current by Ag in YBaCuO-Ag thick films

    Energy Technology Data Exchange (ETDEWEB)

    Dwir, B.; Kellett, B.; Mieville, L.; Pavuna, D. (Institute of Micro- and Opto-electronics, Department of Physics, Swiss Federal Institute of Technology, CH-1015 Lausanne, Switzerland (CH))

    1991-04-15

    The evidence is reported for enhancement of critical current density {ital J}{sub {ital c}} in YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} thick films with the addition of Ag, which is correlated with improvements in structural properties. An improvement of 50% in {ital J}{sub {ital c}} (up to {similar to}500 A/cm{sup 2} at {ital T}=4.2 K) was obtained in films made from YBCO+60wt % Ag powder, fabricated by the spin-on technique on (100) SrTiO{sub 3}, which is correlated with improvements in structure. The resulting films are 10 {mu}m thick, uniform, partially textured, and show good adherence. The critical temperature {ital T}{sub {ital c}} is improved by the addition of Ag, and a reduction in the density of microcracks and in the amount of secondary phases in the sintered films was observed. Normal-state resistivity is reduced by almost three orders of magnitude, making these films potentially useful for electronic applications in interconnects and novel hybrid circuits.

  17. Integration of plasmonic Ag nanoparticles as a back reflector in ultra-thin Cu(In,Ga)Se2 solar cells

    Science.gov (United States)

    Yin, Guanchao; Steigert, Alexander; Andrae, Patrick; Goebelt, Manuela; Latzel, Michael; Manley, Phillip; Lauermann, Iver; Christiansen, Silke; Schmid, Martina

    2015-11-01

    Integration of plasmonic Ag nanoparticles as a back reflector in ultra-thin Cu(In,Ga)Se2 (CIGSe) solar cells is investigated. X-ray photoelectron spectroscopy results show that Ag nanoparticles underneath a Sn:In2O3 back contact could not be thermally passivated even at a low substrate temperature of 440 °C during CIGSe deposition. It is shown that a 50 nm thick Al2O3 film prepared by atomic layer deposition is able to block the diffusion of Ag, clearing the thermal obstacle in utilizing Ag nanoparticles as a back reflector in ultra-thin CIGSe solar cells. Via 3-D finite element optical simulation, it is proved that the Ag nanoparticles show the potential to contribute the effective absorption in CIGSe solar cells.

  18. Theoretical investigation of the thermodynamic properties of metallic thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Vu Van [Vietnam Education Publishing House, 81 Tran Hung Dao, Hanoi (Viet Nam); Phuong, Duong Dai [Hanoi National University of Education, 136 Xuan Thuy, Hanoi (Viet Nam); Hoa, Nguyen Thi [University of Transport and Communications, Lang Thuong, Dong Da, Hanoi (Viet Nam); Hieu, Ho Khac, E-mail: hieuhk@duytan.edu.vn [Institute of Research and Development, Duy Tan University, K7/25 Quang Trung, Danang (Viet Nam)

    2015-05-29

    The thermodynamic properties of metallic thin films with face-centered cubic structure at ambient conditions were investigated using the statistical moment method including the anharmonicity effects of thermal lattice vibrations. The analytical expressions of Helmholtz free energy, lattice parameter, linear thermal expansion coefficient, specific heats at the constant volume and constant pressure were derived in terms of the power moments of the atomic displacements. Numerical calculations of thermodynamic properties have been performed for Au and Al thin films and compared with those of bulk metals. This research proposes that thermodynamic quantities of thin films approach the values of bulk when the thickness of thin film is about 70 nm. - Highlights: • Thermodynamic properties of thin films were investigated using the moment method. • Expressions of Helmholtz energy, expansion coefficient, specific heats were derived. • Calculations for Au, Al thin films were performed and compared with those of bulks.

  19. Thin-liquid-film evaporation at contact line

    Institute of Scientific and Technical Information of China (English)

    Hao WANG; Zhenai PAN; Zhao CHEN

    2009-01-01

    When a liquid wets a solid wall, the extended meniscus near the contact line may be divided into three regions: a nonevaporating region, where the liquid is adsorbed on the wall; a transition region or thin-film region, where effects of long-range molecular forces (disjoining pressure) are felt; and an intrinsic meniscus region, where capillary forces dominate. The thin liquid film, with thickness from nanometers up to micrometers, covering the transition region and part of intrinsic meniscus, is gaining interest due to its high heat transfer rates. In this paper, a review was made of the researches on thin-liquid-film evaporation. The major characteristics of thin film, thin-film modeling based on continuum theory, simulations based on molecular dynamics, and thin-film profile and temperature measurements were summarized.

  20. Metallic Thin-Film Bonding and Alloy Generation

    Science.gov (United States)

    Fryer, Jack Merrill (Inventor); Campbell, Geoff (Inventor); Peotter, Brian S. (Inventor); Droppers, Lloyd (Inventor)

    2016-01-01

    Diffusion bonding a stack of aluminum thin films is particularly challenging due to a stable aluminum oxide coating that rapidly forms on the aluminum thin films when they are exposed to atmosphere and the relatively low meting temperature of aluminum. By plating the individual aluminum thin films with a metal that does not rapidly form a stable oxide coating, the individual aluminum thin films may be readily diffusion bonded together using heat and pressure. The resulting diffusion bonded structure can be an alloy of choice through the use of a carefully selected base and plating metals. The aluminum thin films may also be etched with distinct patterns that form a microfluidic fluid flow path through the stack of aluminum thin films when diffusion bonded together.

  1. Biocompatibility evaluation of sputtered zirconium-based thin film metallic glass-coated steels

    Directory of Open Access Journals (Sweden)

    Subramanian B

    2015-10-01

    Full Text Available Balasubramanian Subramanian,1 Sundaram Maruthamuthu,2 Senthilperumal Thanka Rajan1 1Electrochemical Material Science Division, 2Corrosion and Materials Protection Division, Central Electrochemical Research Institute, Karaikudi, India Abstract: Thin film metallic glasses comprised of Zr48Cu36Al8Ag8 (at.% of approximately 1.5 µm and 3 µm in thickness were prepared using magnetron sputtering onto medical grade 316L stainless steel. Their structural and mechanical properties, in vitro corrosion, and antimicrobial activity were analyzed. The amorphous thin film metallic glasses consisted of a single glassy phase, with an absence of any detectable peaks corresponding to crystalline phases. Elemental composition close to the target alloy was noted from EDAX analysis of the thin film. The surface morphology of the film showed a smooth surface on scanning electron microscopy and atomic force microscopy. In vitro electrochemical corrosion studies indicated that the zirconium-based metallic glass could withstand body fluid, showing superior resistance to corrosion and electrochemical stability. Interactions between the coated surface and bacteria were investigated by agar diffusion, solution suspension, and wet interfacial contact methods. The results indicated a clear zone of inhibition against the growth of microorganisms such as Escherichia coli and Staphylococcus aureus, confirming the antimicrobial activity of the thin film metallic glasses. Cytotoxicity studies using L929 fibroblast cells showed these coatings to be noncytotoxic in nature. Keywords: thin film metallic glasses, sputtering, biocompatibility, corrosion, antimicrobial activity

  2. Anomalous hopping conduction in nanocrystalline/amorphous composites and amorphous semiconductor thin films

    Science.gov (United States)

    Kakalios, James; Bodurtha, Kent

    Composite nanostructured materials consisting of nanocrystals (nc) embedded within a thin film amorphous matrix can exhibit novel opto-electronic properties. Composite films are synthesized in a dual-chamber co-deposition PECVD system capable of producing nanocrystals of material A and embedding then within a thin film matrix of material B. Electronic conduction in composite thin films of hydrogenated amorphous silicon (a-Si:H) containing nc-germanium or nc-silicon inclusions, as well as in undoped a-Si:H, does not follow an Arrhenius temperature dependence, but rather is better described by an anomalous hopping expression (exp[-(To/T)3/4) , as determined from the ``reduced activation energy'' proposed by Zabrodskii and Shlimak. This temperature dependence has been observed in other thin film resistive materials, such as ultra-thin disordered films of Ag, Bi, Pb and Pd; carbon-black polymer composites; and weakly coupled Au and ZnO quantum dot arrays. There is presently no accepted theoretical understanding of this expression. The concept of a mobility edge, accepted for over four decades, appears to not be necessary to account for charge transport in amorphous semiconductors. Supported by NSF-DMR and the Minnesota Nano Center.

  3. A Solid Ag Film Deposited from Solution on Self-assembled Mercaptopropyltrimethoxysilane (MPTS) Monolayer

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Mercaptopropyltrimethoxysilane (MPTS) bearing mercapto groups was used to form self-assembly monolayers (SAMs) on glass substrates by solution extraction. SEM, XRD and rubbing test analysis illustrated that the Ag film on the SAMs-modified glass was more durable than that on the commonly-modified glass and that the crystallinity of Ag film on the SAMs-modified glass was identical with those of the Ag film on the commonly-modified glass and pure Ag.

  4. Stripe glasses in ferromagnetic thin films

    Science.gov (United States)

    Principi, Alessandro; Katsnelson, Mikhail I.

    2016-02-01

    Domain walls in magnetic multilayered systems can exhibit a very complex and fascinating behavior. For example, the magnetization of thin films of hard magnetic materials is in general perpendicular to the thin-film plane, thanks to the strong out-of-plane anisotropy, but its direction changes periodically, forming an alternating spin-up and spin-down stripe pattern. The latter is stabilized by the competition between the ferromagnetic coupling and dipole-dipole interactions, and disappears when a moderate in-plane magnetic field is applied. It has been suggested that such a behavior may be understood in terms of a self-induced stripe glassiness. In this paper we show that such a scenario is compatible with the experimental findings. The strong out-of-plane magnetic anisotropy of the film is found to be beneficial for the formation of both stripe-ordered and glassy phases. At zero magnetic field the system can form a glass only in a narrow interval of fairly large temperatures. An in-plane magnetic field, however, shifts the glass transition towards lower temperatures, therefore enabling it at or below room temperature. In good qualitative agreement with the experimental findings, we show that a moderate in-plane magnetic field of the order of 50 mT can lead to the formation of defects in the stripe pattern, which sets the onset of the glass transition.

  5. Orthogonal Thin Film Photovoltaics on Vertical Nanostructures.

    Science.gov (United States)

    Ahnood, Arman; Zhou, H; Suzuki, Y; Sliz, R; Fabritius, T; Nathan, Arokia; Amaratunga, G A J

    2015-12-01

    Decoupling paths of carrier collection and illumination within photovoltaic devices is one promising approach for improving their efficiency by simultaneously increasing light absorption and carrier collection efficiency. Orthogonal photovoltaic devices are core-shell type structures consisting of thin film photovoltaic stack on vertical nanopillar scaffolds. These types of devices allow charge collection to take place in the radial direction, perpendicular to the path of light in the vertical direction. This approach addresses the inherently high recombination rate of disordered thin films, by allowing semiconductor films with minimal thicknesses to be used in photovoltaic devices, without performance degradation associated with incomplete light absorption. This work considers effects which influence the performance of orthogonal photovoltaic devices. Illumination non-uniformity as light travels across the depth of the pillars, electric field enhancement due to the nanoscale size and shape of the pillars, and series resistance due to the additional surface structure created through the use of pillars are considered. All of these effects influence the operation of orthogonal solar cells and should be considered in the design of vertically nanostructured orthogonal photovoltaics.

  6. Nanomechanics of Ferroelectric Thin Films and Heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yulan; Hu, Shenyang Y.; Chen , L.Q.

    2016-08-31

    The focus of this chapter is to provide basic concepts of how external strains/stresses altering ferroelectric property of a material and how to evaluate quantitatively the effect of strains/stresses on phase stability, domain structure, and material ferroelectric properties using the phase-field method. The chapter starts from a brief introduction of ferroelectrics and the Landau-Devinshire description of ferroelectric transitions and ferroelectric phases in a homogeneous ferroelectric single crystal. Due to the fact that ferroelectric transitions involve crystal structure change and domain formation, strains and stresses can be produced inside of the material if a ferroelectric transition occurs and it is confined. These strains and stresses affect in turn the domain structure and material ferroelectric properties. Therefore, ferroelectrics and strains/stresses are coupled to each other. The ferroelectric-mechanical coupling can be used to engineer the material ferroelectric properties by designing the phase and structure. The followed section elucidates calculations of the strains/stresses and elastic energy in a thin film containing a single domain, twinned domains to complicated multidomains constrained by its underlying substrate. Furthermore, a phase field model for predicting ferroelectric stable phases and domain structure in a thin film is presented. Examples of using substrate constraint and temperature to obtain interested ferroelectric domain structures in BaTiO3 films are demonstrated b phase field simulations.

  7. Thin-film cadmium telluride solar cells

    Science.gov (United States)

    Chu, T. L.

    1986-08-01

    The major objective of this work was to demonstrate CdTe devices grown by chemical vapor deposition (CVD) with a total area greater than 1 cm2 and photovoltic efficiencies of at least 13%. During the period covered, various processing steps were investigated for the preparation of thin-film CdTe heterojunction solar cells of the inverted configuration. Glass coated with fluorine-doped tin oxide was used as the substrate. Thin-film heterojunction solar cells were prepared by depositing p-CdTe films on substrates using CVD and close-spaced sublimation (CSS). Cells prepared from CSS CdTe usually have a higher conversion efficiency than those prepared from CVD CdTe, presumably due to the chemical interaction between CdS and CdTe at the interface during the CVD process. The best cell, about 1.2 sq cm in area, had an AM 1.5 (global) efficiency of 10.5%, and further improvements are expected by optimizing the process parameters.

  8. Polarized Neutron Reflectivity Simulation of Ferromagnet/ Antiferromagnet Thin Films

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yeon; Lee, Jeong Soo

    2008-02-15

    This report investigates the current simulating and fitting programs capable of calculating the polarized neutron reflectivity of the exchange-biased ferromagnet/antiferromagnet magnetic thin films. The adequate programs are selected depending on whether nonspin flip and spin flip reflectivities of magnetic thin films and good user interface are available or not. The exchange-biased systems such as Fe/Cr, Co/CoO, CoFe/IrMn/Py thin films have been simulated successfully with selected programs.

  9. 3D Field Simulation of Magnetic Thin Film Inductor

    OpenAIRE

    FUJIWARA, Toshiyasu; CHOI, Kyung-Ku; SATO, SHIGEKI

    2006-01-01

    The 3D magnetic field simulations with FEM (finite element method) have been performed to predictand understand the performance of Magnetic Thin Film Inductor (MTFl). Inductor structures of planar electroplated Cu spiralcoil, which are sandwiched and underlaid with magnetic thin films, are considered as the simulation models. The inductance increment of 300% compared to air-core inductor was predicted when the sandwiched 5μm thickness magnetic thin film with relative permeability of 600 was a...

  10. Crystal structure of fiber structured pentacene thin films

    OpenAIRE

    2007-01-01

    This PhD thesis presents a technique based on the grazing incidence crystal truncation rod (GI-CTR) X-ray diffraction method used to solve the crystal structure of substrate induced fiber structured organic thin films. The crystal structures of pentacene thin films grown on technologically relevant gate dielectric substrates are reported. It is widely recognized, that the intrinsic charge transport properties in organic thin film transistors (OTFTs) depend strongly on the crystal structur...

  11. Preparation of bismuth telluride thin film by electrochemical atomic layer epitaxy(ECALE)

    Institute of Scientific and Technical Information of China (English)

    ZHU Wen; YANG Junyou; GAO Xianhui; HOU Jie; BAO Siqian; FAN Xian

    2007-01-01

    Thin-layer electrochemical studies of the underpotential deposition(UPD)of Bi and Te on cold rolled silver substrate have been performed.The voltammetric analysis of underpotential shift demonstrates that the initial Te UPD on Bi-covered Ag and Bi UPD on Te-covered Ag fitted UPD dynamics mechanism.A thin film of bismuth telluride was formed by alternately depositing Te and Bi via an automated flow deposition system.X-ray diffraction indicated the deposits of Bi2Te3.Energy Dispersive X-ray Detector quantitative analysis gave a 2:3 stoichiornetric ratio of Bi to Te,which was consistent with X-ray Diffraction results.Electron probe microanalysis of the deposits showed a network structure that results from the surface defects of the cold rolled Ag substrate and the lattice mismatch between substrate and deposit.

  12. Current-induced surface roughness reduction in conducting thin films

    Science.gov (United States)

    Du, Lin; Maroudas, Dimitrios

    2017-03-01

    Thin film surface roughness is responsible for various materials reliability problems in microelectronics and nanofabrication technologies, which requires the development of surface roughness reduction strategies. Toward this end, we report modeling results that establish the electrical surface treatment of conducting thin films as a physical processing strategy for surface roughness reduction. We develop a continuum model of surface morphological evolution that accounts for the residual stress in the film, surface diffusional anisotropy and film texture, film's wetting of the layer that is deposited on, and surface electromigration. Supported by linear stability theory, self-consistent dynamical simulations based on the model demonstrate that the action over several hours of a sufficiently strong and properly directed electric field on a conducting thin film can reduce its surface roughness and lead to a smooth planar film surface. The modeling predictions are in agreement with experimental measurements on copper thin films deposited on silicon nitride layers.

  13. Antibacterial property of Ag nanoparticle-impregnated N-doped titania films under visible light

    Science.gov (United States)

    Wong, Ming-Show; Chen, Chun-Wei; Hsieh, Chia-Chun; Hung, Shih-Che; Sun, Der-Shan; Chang, Hsin-Hou

    2015-07-01

    Photocatalysts produce free radicals upon receiving light energy; thus, they possess antibacterial properties. Silver (Ag) is an antibacterial material that disrupts bacterial physiology. Our previous study reported that the high antibacterial property of silver nanoparticles on the surfaces of visible light-responsive nitrogen-doped TiO2 photocatalysts [TiO2(N)] could be further enhanced by visible light illumination. However, the major limitation of this Ag-TiO2 composite material is its durability; the antibacterial property decreased markedly after repeated use. To overcome this limitation, we developed TiO2(N)/Ag/TiO2(N) sandwich films in which the silver is embedded between two TiO2(N) layers. Various characteristics, including silver and nitrogen amounts, were examined in the composite materials. Various analyses, including electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and ultraviolet-visible absorption spectrum and methylene blue degradation rate analyses, were performed. The antibacterial properties of the composite materials were investigated. Here we revealed that the antibacterial durability of these thin films is substantially improved in both the dark and visible light, by which bacteria, such as Escherichia coli, Streptococcus pyogenes, Staphylococcus aureus, and Acinetobacter baumannii, could be efficiently eliminated. This study demonstrated a feasible approach to improve the visible-light responsiveness and durability of antibacterial materials that contain silver nanoparticles impregnated in TiO2(N) films.

  14. Polycrystalline-thin-film thermophotovoltaic cells

    Science.gov (United States)

    Dhere, Neelkanth G.

    1996-02-01

    Thermophotovoltaic (TPV) cells convert thermal energy to electricity. Modularity, portability, silent operation, absence of moving parts, reduced air pollution, rapid start-up, high power densities, potentially high conversion efficiencies, choice of a wide range of heat sources employing fossil fuels, biomass, and even solar radiation are key advantages of TPV cells in comparison with fuel cells, thermionic and thermoelectric convertors, and heat engines. The potential applications of TPV systems include: remote electricity supplies, transportation, co-generation, electric-grid independent appliances, and space, aerospace, and military power applications. The range of bandgaps for achieving high conversion efficiencies using low temperature (1000-2000 K) black-body or selective radiators is in the 0.5-0.75 eV range. Present high efficiency convertors are based on single crystalline materials such as In1-xGaxAs, GaSb, and Ga1-xInxSb. Several polycrystalline thin films such as Hg1-xCdxTe, Sn1-xCd2xTe2, and Pb1-xCdxTe, etc., have great potential for economic large-scale applications. A small fraction of the high concentration of charge carriers generated at high fluences effectively saturates the large density of defects in polycrystalline thin films. Photovoltaic conversion efficiencies of polycrystalline thin films and PV solar cells are comparable to single crystalline Si solar cells, e.g., 17.1% for CuIn1-xGaxSe2 and 15.8% for CdTe. The best recombination-state density Nt is in the range of 10-15-10-16 cm-3 acceptable for TPV applications. Higher efficiencies may be achieved because of the higher fluences, possibility of bandgap tailoring, and use of selective emitters such as rare earth oxides (erbia, holmia, yttria) and rare earth-yttrium aluminium garnets. As compared to higher bandgap semiconductors such as CdTe, it is easier to dope the lower bandgap semiconductors. TPV cell development can benefit from the more mature PV solar cell and opto

  15. Design and Simulation of the Thin Film Pulse Transformer

    Institute of Scientific and Technical Information of China (English)

    LIU Bao-yuan; SHI Yu; WEN Qi-ye

    2005-01-01

    A new thin film pulse transformer for using in ISND and ADSL systems has been designed based on a domain wall pinning model, the parameters of nano-magnetic thin film such as permeability and coercivity can be calculated. The main properties of the thin film transformer including the size,parallel inductance, Q value and turn ratio have been simulated and optimized. Simulation results show that the thin film transformer can be fairly operated in a frequency range of 0. 001~20 MHz.

  16. Non-local thin films in Casimir force calculations

    CERN Document Server

    Esquivel, R

    2005-01-01

    he Casimir force is calculated between plates with thin metallic coating. Thin films are described with spatially dispersive (nonlocal) dielectric functions. For thin films the nonlocal effects are more relevant than for half-spaces. However, it is shown that even for film thickness smaller than the mean free path for electrons, the difference between local and nonlocal calculations of the Casimir force is of the order of a few tenths of a percent. Thus the local description of thin metallic films is adequate within the current experimental precision and range of separations.

  17. 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.

  18. Sputtering materials for VLSI and thin film devices

    CERN Document Server

    Sarkar, Jaydeep

    2010-01-01

    An important resource for students, engineers and researchers working in the area of thin film deposition using physical vapor deposition (e.g. sputtering) for semiconductor, liquid crystal displays, high density recording media and photovoltaic device (e.g. thin film solar cell) manufacturing. This book also reviews microelectronics industry topics such as history of inventions and technology trends, recent developments in sputtering technologies, manufacturing steps that require sputtering of thin films, the properties of thin films and the role of sputtering target performance on overall p

  19. Physics of thin films advances in research and development

    CERN Document Server

    Hass, Georg; Vossen, John L

    2013-01-01

    Physics of Thin Films: Advances in Research and Development, Volume 12 reviews advances that have been made in research and development concerning the physics of thin films. This volume covers a wide range of preparative approaches, physics phenomena, and applications related to thin films. This book is comprised of four chapters and begins with a discussion on metal coatings and protective layers for front surface mirrors used at various angles of incidence from the ultraviolet to the far infrared. Thin-film materials and deposition conditions suitable for minimizing reflectance changes with

  20. Thin-Film Materials Synthesis and Processing Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides a wide capability for deposition and processing of thin films, including sputter and ion-beam deposition, thermal evaporation, electro-deposition,...