Transport mechanisms and wetting dynamics in molecularly thin films of long-chain alkanes at solid/vapour interface : relation to the solid-liquid phase transition

OpenAIRE

Lazar, Paul

2005-01-01

Wetting and phase transitions play a very important role our daily life. Molecularly thin films of long-chain alkanes at solid/vapour interfaces (e.g. C30H62 on silicon wafers) are very good model systems for studying the relation between wetting behaviour and (bulk) phase transitions. Immediately above the bulk melting temperature the alkanes wet partially the surface (drops). In this temperature range the substrate surface is covered with a molecularly thin ordered, solid-like alkane film (...

Thin solid films deposited by pulsed laser ablating spray

International Nuclear Information System (INIS)

Song Guangle

2002-01-01

The fabricating technique of thin solid films deposited by pulsed laser ablating spray is a new technique. The background from which it came into being and the process of its evolution were briefly described. According to relative documents, basic principle of the technique was dwelt on. Based on the latest documents, the status quo, including the studying abroad and home, was discussed in detail. The advantages, shortcomings, prospect of its utility, the significance of studying as well as critic problems were summarized. Some proposal was suggested

Thin Film Microbatteries

International Nuclear Information System (INIS)

Dudney, Nancy J.

2008-01-01

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

Molecular simulation of freestanding amorphous nickel thin films

Energy Technology Data Exchange (ETDEWEB)

Dong, T.Q. [Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, UMR 8208 CNRS, 5 Boulevard Descartes, 77454 Marne-la-Vallée, Cedex 2 (France); Hoang, V.V., E-mail: vvhoang2002@yahoo.com [Department of Physics, Institute of Technology, National University of Ho Chi Minh City, 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City (Viet Nam); Lauriat, G. [Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, UMR 8208 CNRS, 5 Boulevard Descartes, 77454 Marne-la-Vallée, Cedex 2 (France)

2013-10-31

Size effects on glass formation in freestanding Ni thin films have been studied via molecular dynamics simulation with the n-body Gupta interatomic potential. Atomic mechanism of glass formation in the films is determined via analysis of the spatio-temporal arrangements of solid-like atoms occurred upon cooling from the melt. Solid-like atoms are detected via the Lindemann ratio. We find that solid-like atoms initiate and grow mainly in the interior of the film and grow outward. Their number increases with decreasing temperature and at a glass transition temperature they dominate in the system to form a relatively rigid glassy state of a thin film shape. We find the existence of a mobile surface layer in both liquid and glassy states which can play an important role in various surface properties of amorphous Ni thin films. We find that glass formation is size independent for models containing 4000 to 108,000 atoms. Moreover, structure of amorphous Ni thin films has been studied in details via coordination number, Honeycutt–Andersen analysis, and density profile which reveal that amorphous thin films exhibit two different parts: interior and surface layer. The former exhibits almost the same structure like that found for the bulk while the latter behaves a more porous structure containing a large amount of undercoordinated sites which are the origin of various surface behaviors of the amorphous Ni or Ni-based thin films found in practice. - Highlights: • Glass formation is analyzed via spatio-temporal arrangements of solid-like atoms. • Amorphous Ni thin film exhibits two different parts: surface and interior. • Mobile surface layer enhances various surface properties of the amorphous Ni thin films. • Undercoordinated sites play an important role in various surface activities.

Participation of the Third Order Optical Nonlinearities in Nanostructured Silver Doped Zinc Oxide Thin Solid Films

Directory of Open Access Journals (Sweden)

C. Torres-Torres

2012-01-01

Full Text Available We report the transmittance modulation of optical signals in a nanocomposite integrated by two different silver doped zinc oxide thin solid films. An ultrasonic spray pyrolysis approach was employed for the preparation of the samples. Measurements of the third-order nonlinear optical response at a nonresonant 532 nm wavelength of excitation were performed using a vectorial two-wave mixing. It seems that the separated contribution of the optical nonlinearity associated with each film noticeable differs in the resulting nonlinear effects with respect to the additive response exhibited by the bilayer system. An enhancement of the optical Kerr nonlinearity is predicted for prime number arrays of the studied nanoclusters in a two-wave interaction. We consider that the nanostructured morphology of the thin solid films originates a strong modification of the third-order optical phenomena exhibited by multilayer films based on zinc oxide.

Solid Oxide Fuel Cell Based Upon Colloidal Deposition of Thin Films for Lower Temperature Operation (Preprint)

National Research Council Canada - National Science Library

Reitz, T. L; Xiao, H

2006-01-01

In order to reduce the operating temperature of solid oxide fuel cells (SOFCs), anode-supported cells incorporating thin film electrolytes in conjunction with anode/electrolyte and cathode/electrolyte interlayers were studied...

Preparation and impedance characterization of all-solid-state thin film battery systems

OpenAIRE

Schichtel, Patrick

2018-01-01

In this thesis the behavior and properties of solid-state batteries based on multiple electrodes are analysed. For this purpose thin film systems of the relevant materials are prepared to achieve model system for more detailed analysis of the material specific properties. The characterisation of the systems is carried out with typical physical and electrochemical methods and especially using impedance spectroscopy. The first material analysed in this thesis is Li4Ti5O12 which was recognize...

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...

Grain growth: The key to understand solid-state dewetting of silver thin films

International Nuclear Information System (INIS)

Jacquet, P.; Podor, R.; Ravaux, J.; Teisseire, J.; Gozhyk, I.; Jupille, J.; Lazzari, R.

2016-01-01

The dynamics of solid-state dewetting of polycrystalline silver thin films in oxygen atmosphere was investigated with in situ and real-time environmental Scanning Electron Microscopy at high temperature combined with Atomic Force Microscopy. Three steps were identified during dewetting: induction, hole propagation without specific rim and sintering. Moreover, it was observed that a very selective grain growth, promoted by surface diffusion, plays a key role all along the process.

Sputtering of thin and intermediately thick films of solid deuterium by keV electrons

DEFF Research Database (Denmark)

Svendsen, Winnie Edith; Thestrup Nielsen, Birgitte; Schou, Jørgen

1995-01-01

Sputtering of films of solid deuterium by keV electrons was studied in a cryogenic set-up. The sputtering yield shows a minimum yield of about 4 D2/electron for 1.5 and 2 keV electrons at a thickness slightly larger than the average projected range of the electrons. We suggest that the yield around...... the minimum represents the value closest to a bulk-yield induced by electron bombardment. It may also include contributions from the mechanisms that enhance the yield for thin and very thick films....

Synthesis of nanocrystalline TiO2 thin films by liquid phase ...

Indian Academy of Sciences (India)

WINTEC

goes degradation efficiently in presence of TiO2 thin films by exposing its aqueous solution to .... Figure 6. Photodegradation of IGOR organic dye by a. bare TiO2 thin film and b. ... Meng L-J and Dos Santos M P 1993 Thin Solid Films 226 22.

Low-temperature growth of polycrystalline Ge thin film on glass by in situ deposition and ex situ solid-phase crystallization for photovoltaic applications

International Nuclear Information System (INIS)

Tsao, Chao-Yang; Weber, Juergen W.; Campbell, Patrick; Widenborg, Per I.; Song, Dengyuan; Green, Martin A.

2009-01-01

Poly-crystalline germanium (poly-Ge) thin films have potential for lowering the manufacturing cost of photovoltaic devices especially in tandem solar cells, but high crystalline quality would be required. This work investigates the crystallinity of sputtered Ge thin films on glass prepared by in situ growth and ex situ solid-phase crystallization (SPC). Structural properties of the films were characterized by Raman, X-ray diffraction and ultraviolet-visible reflectance measurements. The results show the transition temperature from amorphous to polycrystalline is between 255 deg. C and 280 deg. C for in situ grown poly-Ge films, whereas the transition temperature is between 400 deg. C and 500 deg. C for films produced by SPC for a 20 h annealing time. The in situ growth in situ crystallized poly-Ge films at 450 deg. C exhibit significantly better crystalline quality than those formed by solid-phase crystallization at 600 deg. C. High crystalline quality at low substrate temperature obtained in this work suggests the poly-Ge films could be promising for use in thin film solar cells on glass.

Thin films and nanomaterials

International Nuclear Information System (INIS)

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

2012-01-01

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

Effect of annealing ambient on anisotropic retraction of film edges during solid-state dewetting of thin single crystal films

Energy Technology Data Exchange (ETDEWEB)

Kim, Gye Hyun; Thompson, Carl V., E-mail: cthomp@mit.edu [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 01239 (United States); Ma, Wen [Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 01239 (United States); Yildiz, Bilge [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 01239 (United States); Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 01239 (United States)

2016-08-21

During solid-state dewetting of thin single crystal films, film edges retract at a rate that is strongly dependent on their crystallographic orientations. Edges with kinetically stable in-plane orientations remain straight as they retract, while those with other in-plane orientations develop in-plane facets as they retract. Kinetically stable edges have retraction rates that are lower than edges with other orientations and thus determine the shape of the natural holes that form during solid-state dewetting. In this paper, measurements of the retraction rates of kinetically stable edges for single crystal (110) and (100) Ni films on MgO are presented. Relative retraction rates of kinetically stable edges with different crystallographic orientations are observed to change under different annealing conditions, and this accordingly changes the initial shapes of growing holes. The surfaces of (110) and (100) films were also characterized using low energy electron diffraction, and different surface reconstructions were observed under different ambient conditions. The observed surface structures were found to correlate with the observed changes in the relative retraction rates of the kinetically stable edges.

Influence of film structure on the dewetting kinetics of thin polymer films in the solvent annealing process.

Science.gov (United States)

Zhang, Huanhuan; Xu, Lin; Lai, Yuqing; Shi, Tongfei

2016-06-28

On a non-wetting solid substrate, the solvent annealing process of a thin polymer film includes the swelling process and the dewetting process. Owing to difficulties in the in situ analysis of the two processes simultaneously, a quantitative study on the solvent annealing process of thin polymer films on the non-wetting solid substrate is extremely rare. In this paper, we design an experimental method by combining spectroscopic ellipsometry with optical microscopy to achieve the simultaneous in situ study. Using this method, we investigate the influence of the structure of swollen film on its dewetting kinetics during the solvent annealing process. The results show that for a thin PS film with low Mw (Mw = 4.1 kg mol(-1)), acetone molecules can form an ultrathin enriched layer between the PS film and the solid substrate during the swelling process. The presence of the acetone enriched layer accounts for the exponential kinetic behavior in the case of a thin PS film with low Mw. However, the acetone enriched layer is not observed in the case of a thin PS film with high Mw (Mw = 400 kg mol(-1)) and the slippage effect of polymer chains is valid during the dewetting process.

Solid phase epitaxial growth of high mobility La:BaSnO_3 thin films co-doped with interstitial hydrogen

International Nuclear Information System (INIS)

Niedermeier, Christian A.; Rhode, Sneha; Fearn, Sarah; Moram, Michelle A.; Ide, Keisuke; Hiramatsu, Hidenori; Hosono, Hideo; Kamiya, Toshio

2016-01-01

This work presents the solid phase epitaxial growth of high mobility La:BaSnO_3 thin films on SrTiO_3 single crystal substrates by crystallization through thermal annealing of nanocrystalline thin films prepared by pulsed laser deposition at room temperature. The La:BaSnO_3 thin films show high epitaxial quality and Hall mobilities up to 26 ± 1 cm"2/Vs. Secondary ion mass spectroscopy is used to determine the La concentration profile in the La:BaSnO_3 thin films, and a 9%–16% La doping activation efficiency is obtained. An investigation of H doping to BaSnO_3 thin films is presented employing H plasma treatment at room temperature. Carrier concentrations in previously insulating BaSnO_3 thin films were increased to 3 × 10"1"9" cm"−"3 and in La:BaSnO_3 thin films from 6 × 10"1"9" cm"−"3 to 1.5 × 10"2"0" cm"−"3, supporting a theoretical prediction that interstitial H serves as an excellent n-type dopant. An analysis of the free electron absorption by infrared spectroscopy yields a small (H,La):BaSnO_3 electron effective mass of 0.27 ± 0.05 m_0 and an optical mobility of 26 ± 7 cm"2/Vs. As compared to La:BaSnO_3 single crystals, the smaller electron mobility in epitaxial thin films grown on SrTiO_3 substrates is ascribed to threading dislocations as observed in high resolution transmission electron micrographs.

The Structure and Stability of Molybdenum Ditelluride Thin Films

Directory of Open Access Journals (Sweden)

Zhouling Wang

2014-01-01

Full Text Available Molybdenum-tellurium alloy thin films were fabricated by electron beam evaporation and the films were annealed in different conditions in N2 ambient. The hexagonal molybdenum ditelluride thin films with well crystallization annealed at 470°C or higher were obtained by solid state reactions. Thermal stability measurements indicate the formation of MoTe2 took place at about 350°C, and a subtle weight-loss was in the range between 30°C and 500°C. The evolution of the chemistry for Mo-Te thin films was performed to investigate the growth of the MoTe2 thin films free of any secondary phase. And the effect of other postdeposition treatments on the film characteristics was also investigated.

Realisation and study of poly-phthalocyanine thin films grafted on solid substrate

International Nuclear Information System (INIS)

Huc, Vincent

1999-01-01

The aim of this work is to develop thin films of phthalocyanines covalently grafted to solid substrates. These thin films are formed of successive monomolecular layers of macrocycles, deposited on the substrate by a 'Merrifield' sequential method. These phthalocyanines have in their centre a metallic ion (such as ruthenium) which ensures the bonding of phthalocyanines on the substrate and the assembling of monolayers consecutive together. The deposition of these monolayers is provided by a succession of two spontaneous exchange ligands reactions between the labile groups L initially bound to ruthenium and to those present on the substrate (preliminary functionalized). The repetition of these two steps allows to consider the controlled formation of phthalocyanines multilayers by self-assembling. The main substrates used are the silicon oxide and the gold. Their different characteristics have imposed the development of separate functionalization and characterization methods. The results obtained with these two substrates are separately described. A second method of construction of successive monolayers of phthalocyanines is described involving a chemical coupling between an amine function carried out by the substrate and an aldehyde function present on the ligands bound on ruthenium. (author) [fr

One-dimensional analysis of plane and radial thin film flows including solid-body rotation

Science.gov (United States)

Thomas, S.; Hankey, W.; Faghri, A.; Swanson, T.

1989-01-01

The flow of a thin liquid film with a free surface along a horizontal plate which emanates from a pressurized vessel is examined by integrating the equations of motion across the thin liquid layer and discretizing the integrated equations using finite difference techniques. The effects of 0-g and solid-body rotation will be discussed. The two cases of interest are plane flow and radial flow. In plane flow, the liquid is considered to be flowing along a channel with no change in the width of the channel, whereas in radial flow the liquid spreads out radially over a disk, so that the area changes along the radius. It is desired to determine the height of the liquid film at any location along the plate of disk, so that the heat transfer from the plate or disk can be found. The possibility that the flow could encounter a hydraulic jump is accounted for.

Structure and Sensor Properties of Thin Ordered Solid Films

Directory of Open Access Journals (Sweden)

Jadwiga Sołoducho

2009-09-01

Full Text Available Miniaturized gas sensors and biosensors based on nanostructured sensing elements have attracted considerable interest because these nanostructured materials can be used to significantly improve sensor sensitivity and the response time. We report here on a generic, reversible sensing platform based on hybrid nanofilms. Thin ordered Langmuir-Blodgett (LB films built of fluorene derivatives were used as effective gas sensors for both oxidative and reductive analytes. A novel immobilization method based on thin LB films as a matrix has been developed for construction of sensing protein layers. Biomolecules can often be incorporated into and immobilized on Langmuir-Blodgett films using adsorption methods or by covalent immobilization of proteins. The sensor sensitisation was achieved by an amphiphilic N-alkyl-bis(thiophenearylenes admixed into the film. The interlaced derivative was expected to facilitate the electron transfer, thereby enhancing the sensor sensitivity. The results suggest that this may be very promising approach for exploring the interactions between proteins and high throughput detection of phenol derivatives in wastewater.

Surfactant induced flows in thin liquid films : an experimental study

NARCIS (Netherlands)

Sinz, D.K.N.

2012-01-01

The topic of the experimental work summarized in my thesis is the flow in thin liquid films induced by non-uniformly distributed surfactants. The flow dynamics as a consequence of the deposition of a droplet of an insoluble surfactant onto a thin liquid film covering a solid substrate where

Capillary bending of a thin polymer film floating on a liquid bath

Science.gov (United States)

Twohig, Timothy; Croll, Andrew B.

Thin elastic films and shells are very important in schemes for the encapsulation and protection of fluids from their environment. Capillary origami is a particularly poignant example of how useful fluid/film structures can be formed. The interactions of fluids on thin-films which themselves lie on another surface (fluid or low friction solid) need to be studied if the differences from fluid-fluid and fluid-solid film interfaces are to be fully appreciated. In this experiment, we examine the triple line that occurs when a fluid is resting on a thin polymer film which is itself floating on a second fluid. The top fluid has a high-energy air/fluid interface which can be minimized by deforming the film in a manner that reduces the total air/fluid interface. We create a one-dimensional experiment in order to isolate the basic physics that occurs as the tension of the top fluid pulls on the thin film. Notably, the 1D geometry removes all the complexity incurred by thin films in biaxial stress states (such as wrinkling, folding and crumpling) from the problem. AFOSR under the Young Investigator Program (FA9550-15-1-0168).

Multi-layer thin-film electrolytes for metal supported solid oxide fuel cells

Science.gov (United States)

Haydn, Markus; Ortner, Kai; Franco, Thomas; Uhlenbruck, Sven; Menzler, Norbert H.; Stöver, Detlev; Bräuer, Günter; Venskutonis, Andreas; Sigl, Lorenz S.; Buchkremer, Hans-Peter; Vaßen, Robert

2014-06-01

A key to the development of metal-supported solid oxide fuel cells (MSCs) is the manufacturing of gas-tight thin-film electrolytes, which separate the cathode from the anode. This paper focuses the electrolyte manufacturing on the basis of 8YSZ (8 mol.-% Y2O3 stabilized ZrO2). The electrolyte layers are applied by a physical vapor deposition (PVD) gas flow sputtering (GFS) process. The gas-tightness of the electrolyte is significantly improved when sequential oxidic and metallic thin-film multi-layers are deposited, which interrupt the columnar grain structure of single-layer electrolytes. Such electrolytes with two or eight oxide/metal layers and a total thickness of about 4 μm obtain leakage rates of less than 3 × 10-4 hPa dm3 s-1 cm-2 (Δp: 100 hPa) at room temperature and therefore fulfill the gas tightness requirements. They are also highly tolerant with respect to surface flaws and particulate impurities which can be present on the graded anode underground. MSC cell tests with double-layer and multilayer electrolytes feature high power densities more than 1.4 W cm-2 at 850 °C and underline the high potential of MSC cells.

Development of alpha spectroscopy method with solid state nuclear track detector using aluminium thin films

International Nuclear Information System (INIS)

Dwaikat, N.

2015-10-01

This work presents the development of alpha spectroscopy method with Solid-state nuclear track detectors using aluminum thin films. The resolution of this method is high, and it is able to discriminate between alpha particles at different incident energy. It can measure the exact number of alpha particles at specific energy without needing a calibration of alpha track diameter versus alpha energy. This method was tested by using Cf-252 alpha standard source at energies 5.11 MeV, 3.86 MeV and 2.7 MeV, which produced by the variation of detector -standard source distance. On front side, two detectors were covered with two Aluminum thin films and the third detector was kept uncovered. The thickness of Aluminum thin films was selected carefully (using SRIM 2013) such that one of the films will block the lower two alpha particles (3.86 MeV and 2.7 MeV) and the alpha particles at higher energy (5.11 MeV) can penetrate the film and reach the detectors surface. The second thin film will block alpha particles at lower energy of 2.7 MeV and allow alpha particles at higher two energies (5.11 MeV and 3.86 MeV) to penetrate and produce tracks. For uncovered detector, alpha particles at three different energies can produce tracks on it. For quality assurance and accuracy, the detectors were mounted on thick enough copper substrates to block exposure from the backside. The tracks on the first detector are due to alpha particles at energy of 5.11 MeV. The difference between the tracks number on the first detector and the tracks number on the second detector is due to alpha particles at energy of 3.8 MeV. Finally, by subtracting the tracks number on the second detector from the tracks number on the third detector (uncovered), we can find the tracks number due to alpha particles at energy 2.7 MeV. After knowing the efficiency calibration factor, we can exactly calculate the activity of standard source. (Author)

Development of alpha spectroscopy method with solid state nuclear track detector using aluminium thin films

Energy Technology Data Exchange (ETDEWEB)

Dwaikat, N., E-mail: ndwaikat@kfupm.edu.sa [King Fahd University of Petroleum and Minerals, College of Sciences, Department of Physics, Dhahran 31261 (Saudi Arabia)

2015-10-15

This work presents the development of alpha spectroscopy method with Solid-state nuclear track detectors using aluminum thin films. The resolution of this method is high, and it is able to discriminate between alpha particles at different incident energy. It can measure the exact number of alpha particles at specific energy without needing a calibration of alpha track diameter versus alpha energy. This method was tested by using Cf-252 alpha standard source at energies 5.11 MeV, 3.86 MeV and 2.7 MeV, which produced by the variation of detector -standard source distance. On front side, two detectors were covered with two Aluminum thin films and the third detector was kept uncovered. The thickness of Aluminum thin films was selected carefully (using SRIM 2013) such that one of the films will block the lower two alpha particles (3.86 MeV and 2.7 MeV) and the alpha particles at higher energy (5.11 MeV) can penetrate the film and reach the detectors surface. The second thin film will block alpha particles at lower energy of 2.7 MeV and allow alpha particles at higher two energies (5.11 MeV and 3.86 MeV) to penetrate and produce tracks. For uncovered detector, alpha particles at three different energies can produce tracks on it. For quality assurance and accuracy, the detectors were mounted on thick enough copper substrates to block exposure from the backside. The tracks on the first detector are due to alpha particles at energy of 5.11 MeV. The difference between the tracks number on the first detector and the tracks number on the second detector is due to alpha particles at energy of 3.8 MeV. Finally, by subtracting the tracks number on the second detector from the tracks number on the third detector (uncovered), we can find the tracks number due to alpha particles at energy 2.7 MeV. After knowing the efficiency calibration factor, we can exactly calculate the activity of standard source. (Author)

Ultra-thin film encapsulation processes for micro-electro-mechanical devices and systems

International Nuclear Information System (INIS)

Stoldt, Conrad R; Bright, Victor M

2006-01-01

A range of physical properties can be achieved in micro-electro-mechanical systems (MEMS) through their encapsulation with solid-state, ultra-thin coatings. This paper reviews the application of single source chemical vapour deposition and atomic layer deposition (ALD) in the growth of submicron films on polycrystalline silicon microstructures for the improvement of microscale reliability and performance. In particular, microstructure encapsulation with silicon carbide, tungsten, alumina and alumina-zinc oxide alloy ultra-thin films is highlighted, and the mechanical, electrical, tribological and chemical impact of these overlayers is detailed. The potential use of solid-state, ultra-thin coatings in commercial microsystems is explored using radio frequency MEMS as a case study for the ALD alloy alumina-zinc oxide thin film. (topical review)

A novel application of the CuI thin film for preparing thin copper nanowires

International Nuclear Information System (INIS)

Shi Shuo; Sun Jialin; Zhang Jianhong; Cao Yang

2005-01-01

We present a novel application of the CuI thin film for preparing thin copper nanowires under a direct current electric field (DCEF). The CuI thin film was used as a medium for transmitting cuprous ions during the growing process of copper nanowires. As electrodes are the source of cuprous ions, high-purity copper films were deposited on both ends of the CuI thin film. At 353 K, under whole solid condition, without any templates, and having applied a DCEF of 1.5x10 4 V/m, cuprous ions were generated at the anode and migrated towards the cathode through the CuI film. At the edge of the cathode, cuprous ions obtained electrons and congregated to form a disordered thin copper nanowires bundle. The SEM images showed that these copper nanowires were from 10 to 20 nm in diameter and several hundred nanometers in length. The effect of the electric field intensity and the growth temperature on the diameter of the nanowires was also studied

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.

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.

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. PMID:24523630

Synthesis and characterization of electrolyte-grade 10%Gd-doped ceria thin film/ceramic substrate structures for solid oxide fuel cells

DEFF Research Database (Denmark)

Chourashiya, M. G.; Bharadwaj, S. R.; Jadhav, L. D.

2010-01-01

In the present research, spray pyrolysis technique is employed to synthesize 10%Gd-doped ceria (GDC) thin films on ceramic substrates with an intention to use the "film/substrate" structure in solid oxide fuel cells. GDC films deposited on GDC substrate showed enhanced crystallite formation....... In case of NiO-GDC composite substrate, the thickness of film was higher (∼ 13 μm) as compared to the film thickness on GDC substrate (∼ 2 μm). The relative density of the films deposited on both the substrates was of the order of 95%. The impedance measurements revealed that ionic conductivity of GDC...

Rapid thermal annealing of Ti-rich TiNi thin films: A new approach to fabricate patterned shape memory thin films

International Nuclear Information System (INIS)

Motemani, Y.; Tan, M.J.; White, T.J.; Huang, W.M.

2011-01-01

This paper reports the rapid thermal annealing (RTA) of Ti-rich TiNi thin films, synthesized by the co-sputtering of TiNi and Ti targets. Long-range order of aperiodic alloy could be achieved in a few seconds with the optimum temperature of 773 K. Longer annealing (773 K/240 s), transformed the film to a poorly ordered vitreous phase, suggesting a novel method for solid state amorphization. Reitveld refinement analyses showed significant differences in structural parameters of the films crystallized by rapid and conventional thermal annealing. Dependence of the elastic modulus on the valence electron density (VED) of the crystallized films was studied. It is suggested that RTA provides a new approach to fabricate patterned shape memory thin films.

Nano structured TiO2 thin films by polymeric precursor method

International Nuclear Information System (INIS)

Stroppa, Daniel Grando; Giraldi, Tania Regina; Leite, Edson Roberto; Varela, Jose Arana; Longo, Elson

2008-01-01

This work focuses in optimizing setup for obtaining TiO 2 thin films by polymeric precursor route due to its advantages on stoichiometric and morphological control. Precursor stoichiometry, synthesis pH, solids concentration and rotation speed at deposition were optimized evaluating thin films morphology and thickness. Thermogravimetry and NMR were applied for precursor's characterization and AFM, XRD and ellipsometry for thin films evaluation. Results showed successful attainment of homogeneous nanocrystalline anatase TiO 2 thin films with outstanding control over morphological characteristics, mean grain size of 17 nm, packing densities between 57 and 75%, estimated surface areas of 90 m 2 /g and monolayers thickness within 20 and 128 nm. (author)

Thin-film Rechargeable Lithium Batteries for Implantable Devices

Science.gov (United States)

Bates, J. B.; Dudney, N. J.

1997-05-01

Thin films of LiCoO{sub 2} have been synthesized in which the strongest x ray reflection is either weak or missing, indicating a high degree of preferred orientation. Thin film solid state batteries with these textured cathode films can deliver practical capacities at high current densities. For example, for one of the cells 70% of the maximum capacity between 4.2 V and 3 V ({approximately}0.2 mAh/cm{sup 2}) was delivered at a current of 2 mA/cm{sup 2}. When cycled at rates of 0.1 mA/cm{sup 2}, the capacity loss was 0.001%/cycle or less. The reliability and performance of Li LiCoO{sub 2} thin film batteries make them attractive for application in implantable devices such as neural stimulators, pacemakers, and defibrillators.

Adhesion Dynamics in Probing Micro- and Nanoscale Thin Solid Films

Directory of Open Access Journals (Sweden)

Xiaoling He

2008-01-01

Full Text Available This study focuses on modeling the probe dynamics in scratching and indenting thin solid films at micro- and nanoscales. The model identifies bifurcation conditions that define the stick-slip oscillation patterns of the tip. It is found that the local energy fluctuations as a function of the inelastic deformation, defect formation, material properties, and contact parameters determine the oscillation behavior. The transient variation of the localized function makes the response nonlinear at the adhesion junction. By quantifying the relation between the bifurcation parameters and the oscillation behavior, this model gives a realistic representation of the complex adhesion dynamics. Specifically, the model establishes the link between the stick-slip behavior and the inelastic deformation and the local potentials. This model justifies the experimental observations and the molecular dynamics simulation of the adhesion and friction dynamics in both the micro- and nanoscale contact.

Deposition and characterisation of epitaxial oxide thin films for SOFCs

KAUST Repository

Santiso, José ; Burriel, Mó nica

2010-01-01

This paper reviews the recent advances in the use of thin films, mostly epitaxial, for fundamental studies of materials for solid oxide fuel cell (SOFC) applications. These studies include the influence of film microstructure, crystal orientation

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...

Photoluminescence properties of perovskite multilayer thin films

Energy Technology Data Exchange (ETDEWEB)

Macario, Leilane Roberta; Longo, Elson, E-mail: leilanemacario@gmail.com [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil); Mazzo, Tatiana Martelli [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil); Bouquet, Valerie; Deputier, Stephanie; Ollivier, Sophie; Guilloux-Viry, Maryline [Universite de Rennes (France)

2016-07-01

Full text: The knowledge of the optical properties of thin films is important in many scientific, technological and industrial applications of thin films such as photoconductivity, solar energy, photography, and numerous other applications [1]. In this study, perovskite type oxides were grown by pulsed laser deposition [2] in order to obtain thin films with applicable optical properties. The LaNiO{sub 3} (LN), BaTiO{sub 3} (BT) and KNbO{sub 3} (KNb) targets were prepared by solid-state reaction. The X-ray Diffraction revealed the presence of the desired phases, containing the elements of interest in the targets and in the thin films that were produced. The LN, BT and KNb thin films were polycrystalline and the corresponding diffraction peaks were indexed in the with JCPDS cards n. 00-033-0711, n. 00-005-0626, and n. 00-009-0156, respectively. The multilayers films were polycrystalline. The majority of the micrographs obtained by scanning electron microscopy presented films with a thickness from 100 to 400 nm. The photoluminescent (PL) emission spectra of thin films show different broad bands that occupies large region of the visible spectrum, ranging from about 300-350 to 600-650 nm of the electromagnetic spectrum. The PL emission is associated with the order-disorder structural, even small structural changes can modify the interactions between electronic states. The structural disorder results in formation of new energy levels in the forbidden region. The proximity or distance of these new energy levels formed in relation to valence band and to the conduction band results in PL spectra located at higher or lower energies. These interactions change the electronic states which can be influenced by defects, particularly the interface defects between the layers of the thin films. The presence of defects results in changes in the broad band matrix intensity and in displacement of the PL emission maximum. (author)

Thin-film photovoltaic technology

Energy Technology Data Exchange (ETDEWEB)

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

2010-07-01

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

Q-switched all-solid-state lasers and application in processing of thin-film solar cell

Science.gov (United States)

Liu, Liangqing; Wang, Feng

2009-08-01

Societal pressure to renewable clean energy is increasing which is expected to be used as part of an overall strategy to address global warming and oil crisis. Photovoltaic energy conversion devices are on a rapidly accelerating growth path driven by government, of which the costs and prices lower continuously. The next generation thin-film devices are considered to be more efficiency and greatly reduced silicon consumption, resulting in dramatically lower per unit fabrication costs. A key aspect of these devices is patterning large panels to create a monolithic array of series-interconnected cells to form a low current, high voltage module. This patterning is accomplished in three critical scribing processes called P1, P2, and P3. All-solid-state Q-switched lasers are the technology of choice for these processes, due to their advantages of compact configuration, high peak-value power, high repeat rate, excellent beam quality and stability, delivering the desired combination of high throughput and narrow, clean scribes. The end pumped all-solid-state lasers could achieve 1064nm IR resources with pulse width of nanoseconds adopting acoustic-optics Q-switch, shorter than 20ns. The repeat rate is up to 100kHz and the beam quality is close to diffraction limit. Based on this, 532nm green lasers, 355nm UV lasers and 266nm DUV lasers could be carried out through nonlinear frequency conversion. Different wave length lasers are chose to process selective materials. For example, 8-15 W IR lasers are used to scribe the TCO film (P1); 1-5 W green lasers are suitable for scribing the active semiconductor layers (P2) and the back contact layers (P3). Our company, Wuhan Lingyun Photo-electronic System Co. Ltd, has developed 20W IR and 5W green end-pumped Q-switched all-solid-state lasers for thin-film solar industry. Operating in high repeat rates, the speed of processing is up to 2.0 m/s.

Deposition and characterisation of epitaxial oxide thin films for SOFCs

KAUST Repository

Santiso, José

2010-10-24

This paper reviews the recent advances in the use of thin films, mostly epitaxial, for fundamental studies of materials for solid oxide fuel cell (SOFC) applications. These studies include the influence of film microstructure, crystal orientation and strain in oxide ionic conducting materials used as electrolytes, such as fluorites, and in mixed ionic and electronic conducting materials used as electrodes, typically oxides with perovskite or perovskite-related layered structures. The recent effort towards the enhancement of the electrochemical performance of SOFC materials through the deposition of artificial film heterostructures is also presented. These thin films have been engineered at a nanoscale level, such as the case of epitaxial multilayers or nanocomposite cermet materials. The recent progress in the implementation of thin films in SOFC devices is also reported. © 2010 Springer-Verlag.

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

Thin film-XRF determination of uranium following thin-film solid phase extraction

Energy Technology Data Exchange (ETDEWEB)

Hassan, Jalal, E-mail: jalalhassan@ut.ac.ir [Department of Toxicology, Faculty of Veterinary Medicine, University of Tehran (Iran, Islamic Republic of); Hosseini, Seyed M.; Mozaffari, Shahla [Department of Chemistry, Payame Noor University, Tehran (Iran, Islamic Republic of); Jahanparast, Babak; Karbasi, Mohammad H. [Iranian Mineral Processing Research Center, Ministry of Industry and Mineral, Karaj (Iran, Islamic Republic of)

2014-07-01

A sensitive method based on the preconcentration of uranium on modified filter paper (thin film) has been developed to determinate this element in water and soil samples by wavelength dispersive X-ray fluorescence. Uranium (VI) extraction from nitric acid medium by trioctyl phosphine (TOPO) from 100 mL of sample was carried out. The effects of nitric acid concentration, TOPO concentration and sample breakthrough on uranium extraction were investigated in this study. The proposed method provided good linearity from 7 to 1000 μg and the limit of detection (LOD), based on a signal-to noise ratio (S/N) of 3, was 2.5 μg. (author)

Multiferroic iron oxide thin films at room temperature

Czech Academy of Sciences Publication Activity Database

Gich, M.; Fina, I.; Morelli, Alessio; Sánchez, F.; Alexe, M.; Gazquez, J.; Fontcuberta, J.; Roig, A.

2014-01-01

Roč. 26, č. 27 (2014), s. 4645-4652 ISSN 0935-9648 Institutional support: RVO:68378271 Keywords : multiferroic * iron oxide * thin film Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 17.493, year: 2014

Dense zig-zag microstructures in YSZ thin films by pulsed laser deposition

Science.gov (United States)

Stender, Dieter; Schäuble, Nina; Weidenkaff, Anke; Montagne, Alex; Ghisleni, Rudy; Michler, Johann; Schneider, Christof W.; Wokaun, Alexander; Lippert, Thomas

2015-01-01

The very brittle oxygen ion conductor yttria stabilized zirconia (YSZ) is a typical solid electrolyte for miniaturized thin film fuel cells. In order to decrease the fuel cell operating temperature, the thickness of yttria stabilized zirconia thin films is reduced. Often, these thin membranes suffer from mechanical failure and gas permeability. To improve these mechanical issues, a glancing angle deposition approach is used to grow yttria stabilized zirconia thin films with tilted columnar structures. Changes of the material flux direction during the deposition result in a dense, zigzag-like structure with columnar crystallites. This structure reduces the elastic modulus of these membranes as compared to columnar yttria stabilized zirconia thin films as monitored by nano-indentation which makes them more adaptable to applied stress.

Dense zig-zag microstructures in YSZ thin films by pulsed laser deposition

Directory of Open Access Journals (Sweden)

Dieter Stender

2015-01-01

Full Text Available The very brittle oxygen ion conductor yttria stabilized zirconia (YSZ is a typical solid electrolyte for miniaturized thin film fuel cells. In order to decrease the fuel cell operating temperature, the thickness of yttria stabilized zirconia thin films is reduced. Often, these thin membranes suffer from mechanical failure and gas permeability. To improve these mechanical issues, a glancing angle deposition approach is used to grow yttria stabilized zirconia thin films with tilted columnar structures. Changes of the material flux direction during the deposition result in a dense, zigzag-like structure with columnar crystallites. This structure reduces the elastic modulus of these membranes as compared to columnar yttria stabilized zirconia thin films as monitored by nano-indentation which makes them more adaptable to applied stress.

Long-Wave Infrared (LWIR) Molecular Laser-Induced Breakdown Spectroscopy (LIBS) Emissions of Thin Solid Explosive Powder Films Deposited on Aluminum Substrates.

Science.gov (United States)

Yang, Clayton S-C; Jin, Feng; Trivedi, Sudhir B; Brown, Ei E; Hommerich, Uwe; Tripathi, Ashish; Samuels, Alan C

2017-04-01

Thin solid films made of high nitro (NO 2 )/nitrate (NO 3 ) content explosives were deposited on sand-blasted aluminum substrates and then studied using a mercury-cadmium-telluride (MCT) linear array detection system that is capable of rapidly capturing a broad spectrum of atomic and molecular laser-induced breakdown spectroscopy (LIBS) emissions in the long-wave infrared region (LWIR; ∼5.6-10 µm). Despite the similarities of their chemical compositions and structures, thin films of three commonly used explosives (RDX, HMX, and PETN) studied in this work can be rapidly identified in the ambient air by their molecular LIBS emission signatures in the LWIR region. A preliminary assessment of the detection limit for a thin film of RDX on aluminum appears to be much lower than 60 µg/cm 2 . This LWIR LIBS setup is capable of rapidly probing and charactering samples without the need for elaborate sample preparation and also offers the possibility of a simultaneous ultraviolet visible and LWIR LIBS measurement.

Measurement of interactions between solid particles, liquid droplets, and/or gas bubbles in a liquid using an integrated thin film drainage apparatus.

Science.gov (United States)

Wang, Louxiang; Sharp, David; Masliyah, Jacob; Xu, Zhenghe

2013-03-19

A novel device was designed to measure drainage dynamics of thin liquid films confined between a solid particle, an immiscible liquid droplet, and/or gas bubble. Equipped with a bimorph force sensor, a computer-interfaced video capture, and a data acquisition system, the newly designed integrated thin film drainage apparatus (ITFDA) allows for the direct and simultaneous measurements of force barrier, true film drainage time, and bubble/droplet deformation under a well-controlled external force, receding and advancing contact angles, capillary force, and adhesion (detachment) force between an air bubble or oil droplet and a solid, a liquid, or an air bubble in an immiscible liquid. Using the diaphragm of a high-frequency speaker as the drive mechanism for the air bubble or oil droplet attached to a capillary tube, this newly designed device is capable of measuring forces over a wide range of hydrodynamic conditions, including bubble approach and retract velocities up to 50 mm/s and displacement range up to 1 mm. The results showed that the ITFDA was capable of measuring hydrodynamic resistance, film drainage time, and other important physical parameters between air bubbles and solid particles in aqueous solutions. As an example of illustrating the versatility, the ITFDA was also applied to other important systems such as interactions between air bubble and oil droplet, two air bubbles, and two oil droplets in an aqueous solution.

Influence of annealing on texture properties of cerium oxide thin films

International Nuclear Information System (INIS)

Arunkumar, P.; Suresh Babu, K.; Ramaseshan, R.; Dash, S.

2013-01-01

Future power demand needs an energy source with higher efficiency, better power density, clean energy and fuel flexibility. Solid oxide fuel cell (SOFC) is one of the potential sources for future needs. Though the polymer and direct methanol based electrolyte are much suitable, for versatile applications (portable devices) they are having major challenges such as design, platinum based catalyst, lower power density and fuel flexibility (free from hydrocarbons). However, in SOFC the high operating temperature is the only major issue. Operating temperature of SOFC could be reduced by proper selection of electrolyte material which should have minimum ionic conductivity of 0.1 Scm -1 at reduced activation energy. This can be achieved by thin film based doped cerium oxide electrolyte for SOFC, leads to Intermediate Temperature Solid Oxide Fuel Cell (ITSOFC). In the present work, we focus on the synthesis of cerium oxide and 20 mol % samarium doped cerium oxide (SDC) nanoparticles by co-precipitation method and to synthesis thin films of the same. Pellets of those powders were heat treated at different temperatures and used as targets for e-beam evaporation to fabricate thin film based electrolyte. Stoichiometry of both powders and thin films were confirmed by XRF and EPMA. GIXRD profiles of ceria and SDC thin films are shown below and a preferred orientation effect is observed in SDC films. In SDC films the X-ray peaks have a shift towards lower angles, due to the difference in ionic radii of Ce 4+ and Sm 3+ . The band gap of CeO 2 (2.88 eV) from optical absorption technique indicates the presence of Ce 3+ with Ce 4+ , indirectly shows the concentration of oxygen vacancies which is required for the thin film electrolyte

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.

Repeated Solid-state Dewetting of Thin Gold Films for Nanogap-rich Plasmonic Nanoislands.

Science.gov (United States)

Kang, Minhee; Park, Sang-Gil; Jeong, Ki-Hun

2015-10-15

This work reports a facile wafer-level fabrication for nanogap-rich gold nanoislands for highly sensitive surface enhanced Raman scattering (SERS) by repeating solid-state thermal dewetting of thin gold film. The method provides enlarged gold nanoislands with small gap spacing, which increase the number of electromagnetic hotspots and thus enhance the extinction intensity as well as the tunability for plasmon resonance wavelength. The plasmonic nanoislands from repeated dewetting substantially increase SERS enhancement factor over one order-of-magnitude higher than those from a single-step dewetting process and they allow ultrasensitive SERS detection of a neurotransmitter with extremely low Raman activity. This simple method provides many opportunities for engineering plasmonics for ultrasensitive detection and highly efficient photon collection.

thin films

Indian Academy of Sciences (India)

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

On dewetting of thin films due to crystallization (crystallization dewetting).

Science.gov (United States)

Habibi, Mehran; Rahimzadeh, Amin; Eslamian, Morteza

2016-03-01

Drying and crystallization of a thin liquid film of an ionic or a similar solution can cause dewetting in the resulting thin solid film. This paper aims at investigating this type of dewetting, herein termed "crystallization dewetting", using PbI2 dissolved in organic solvents as the model solution. PbI2 solid films are usually used in X-ray detection and lead halide perovskite solar cells. In this work, PbI2 films are fabricated using spin coating and the effect of major parameters influencing the crystallization dewetting, including the type of the solvent, solution concentration, drying temperature, spin speed, as well as imposed vibration on the substrate are studied on dewetting, surface profile and coverage, using confocal scanning laser microscopy. Simplified hydrodynamic governing equations of crystallization in thin films are presented and using a mathematical representation of the process, it is phenomenologically demonstrated that crystallization dewetting occurs due to the absorption and consumption of the solution surrounding a growing crystal. Among the results, it is found that a low spin speed (high thickness), a high solution concentration and a low drying temperature promote crystal growth, and therefore crystallization dewetting. It is also shown that imposed vibration on the substrate can affect the crystal size and crystallization dewetting.

Theoretical study of the transmission of low-energy (0-10 eV) electrons through thin-film organic molecular solids: benzene

International Nuclear Information System (INIS)

Goulet, T.; Jay-Gerin, J.-P.

1986-01-01

A theoretical study of the transmission of low-energy (0 to 10 eV) electrons incident from vacuum through thin-film organic molecular solids deposited on a cold metal substrate is presented and developed for the specific case of solid benzene. In essence, using a semiclassical description of electron transport in solids with an energy-independent scattering mean free path and assuming an isotropic electron scattering, the behavior of a penetrating electron in the film is simulated when a large number of scattering events are present. The good agreement between the calculated electron transmission spectra and those obtained experimentally indicates that our study provides a realistic description of the electron transport in the film, and accounts for the influence of the various electron-molecule scattering processes upon the energy dependence of the transmitted current. In particular, we show that the excitonic subionization energy losses are at the origin of the main structures of the observed electron transmission spectra. It is also shown that our study can successfully be used to estimate the probabilities of the various electron scattering processes which occur in the film, as well as the electron mean free path (l). For solid benzene, l is about 8 A in the considered electron energy range. (author)

Solid phase crystallized polycrystalline thin-films on glass from evaporated silicon for photovoltaic applications

International Nuclear Information System (INIS)

Song Dengyuan; Inns, Daniel; Straub, Axel; Terry, Mason L.; Campbell, Patrick; Aberle, Armin G.

2006-01-01

Polycrystalline silicon (poly-Si) thin-films are made on planar and textured glass substrates by solid phase crystallization (SPC) of in situ doped amorphous silicon (a-Si) deposited by electron-beam evaporation. These materials are referred to by us as EVA materials (SPC of evaporated a-Si). The properties of EVA poly-Si films are characterised by Raman microscopy, transmission electron microscopy, and X-ray diffraction. A narrow and symmetrical Raman peak at a wave number of about 520 cm -1 is observed for all samples, showing that the films are fully crystallized. X-ray diffraction (XRD) reveals that the films are preferentially (111)-oriented. Furthermore, the full width at half maximum of the dominant (111) XRD peaks indicates that the structural quality of the films is affected by the a-Si deposition temperature and the surface morphology of the glass substrates. A-Si deposition at 200 instead of 400 deg. C leads to an enhanced poly-Si grain size. On textured glass, the addition of a SiN barrier layer between the glass and the Si improves the poly-Si material quality. No such effect occurs on planar glass. Mesa-type solar cells are made from these EVA films on planar and textured glass. A strong correlation between the cells' current-voltage characteristics and their crystalline material quality is observed

Thin films of molecular materials synthesized from fisher's carbene ferrocenyl: Film formation and electrical properties

International Nuclear Information System (INIS)

Sanchez-Vergara, M.E.; Ortiz, A.; Alvarez-Toledano, C.; Moreno, A.; Alvarez, J.R.

2008-01-01

The synthesis of materials from Fisher's carbene ferrocenyl of the elements chromium, molybdenum and tungsten was carried out. The Fisher's compounds that were synthesized included the following combinations of two different metallic atoms: iron with chromium, iron with molybdenum and iron with tungsten. The molecular solids' preparation was done in electro-synthesis cells with platinum electrodes. Thin films were prepared by vacuum thermal evaporation on quartz substrates and crystalline silicon wafers. Pellets and thin films from these compounds were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive spectroscopy, atomic force microscopy and ellipsometry. The powder and thin films synthesized from these materials show the same intra-molecular bonds shown by infrared spectroscopy results, suggesting that thermal evaporation does not alter these bonds in spite of the thin films being amorphous, in contrast with other bimetallic complexes where material decomposition occurs. The differences in the conductivity values of the prepared films are very small, so they may be attributed to the different metallic ions employed in each case. The tungsten complex exhibits a higher conductivity than the molybdenum and chromium complexes at room temperature. Electrical conductivity values found for thin films are higher than for pellets made of the same molecular materials

Simultaneous reflectometry and interferometry for measuring thin-film thickness and curvature

Science.gov (United States)

Arends, A. A.; Germain, T. M.; Owens, J. F.; Putnam, S. A.

2018-05-01

A coupled reflectometer-interferometer apparatus is described for thin-film thickness and curvature characterization in the three-phase contact line region of evaporating fluids. Validation reflectometry studies are provided for Au, Ge, and Si substrates and thin-film coatings of SiO2 and hydrogel/Ti/SiO2. For interferometry, liquid/air and solid/air interferences are studied, where the solid/air samples consisted of glass/air/glass wedges, cylindrical lenses, and molded polydimethylsiloxane lenses. The liquid/air studies are based on steady-state evaporation experiments of water and isooctane on Si and SiO2/Ti/SiO2 wafers. The liquid thin-films facilitate characterization of both (i) the nano-scale thickness of the absorbed fluid layer and (ii) the macro-scale liquid meniscus thickness, curvature, and curvature gradient profiles. For our validation studies with commercial lenses, the apparatus is shown to measure thickness profiles within 4.1%-10.8% error.

Thin film structures and phase stability

International Nuclear Information System (INIS)

Clemens, B.M.; Johnson, W.L.

1990-01-01

This was a two day symposium, with invited and contributed papers as well as an evening poster session. The first day concentrated on solid state reactions with invited talks by Lindsay Greer from the University of Cambridge, King Tu from IBM Yorktown Heights, and Carl Thompson from MIT. Professor Greer observed that the diffusion of Zr is 10 6 times slower than that of Ni in amorphous NiZr, confirming that Ni is the mobile species in solid state amorphization. King Tu explained the formation of metastable phases in this film diffusion couples by the concept of maximum rate of free energy change. Carl Thompson discussed the formation of amorphous phases in metal silicon systems, and discussed a two stage nucleation and growth process. The contributed papers also generated discussion on topics such as phase segregation, amorphous silicide formation, room temperature oxidation of silicon, and nucleation during ion beam irradiation. There was a lively poster session on Monday evening with papers on a wide variety of topics covering the general area of thin film science. The second day had sessions Epitaxy and Multilayer Structure I and II, with the morning focussing on epitaxial and heteroepitaxial growth of thin films. Robin Farrow of IBM Almaden led off with an invited talk where he reported on some remarkable success he and his co-workers have had in growing single crystal epitaxial thin films and superlattices of silver, iron, cobalt and platinum on GaAs. This was followed by several talks on epitaxial growth and characterization. The afternoon focused on interfaces and structure of multilayered materials. A session on possible stress origins of the supermodulus effect was highlighted by lively interaction from the audience. Most of the papers presented at the symposium are presented in this book

Nucleation and strain-stabilization during organic semiconductor thin film deposition.

Science.gov (United States)

Li, Yang; Wan, Jing; Smilgies, Detlef-M; Bouffard, Nicole; Sun, Richard; Headrick, Randall L

2016-09-07

The nucleation mechanisms during solution deposition of organic semiconductor thin films determine the grain morphology and may influence the crystalline packing in some cases. Here, in-situ optical spectromicroscopy in reflection mode is used to study the growth mechanisms and thermal stability of 6,13-bis(trisopropylsilylethynyl)-pentacene thin films. The results show that the films form in a supersaturated state before transforming to a solid film. Molecular aggregates corresponding to subcritical nuclei in the crystallization process are inferred from optical spectroscopy measurements of the supersaturated region. Strain-free solid films exhibit a temperature-dependent blue shift of optical absorption peaks due to a continuous thermally driven change of the crystalline packing. As crystalline films are cooled to ambient temperature they become strained although cracking of thicker films is observed, which allows the strain to partially relax. Below a critical thickness, cracking is not observed and grazing incidence X-ray diffraction measurements confirm that the thinnest films are constrained to the lattice constants corresponding to the temperature at which they were deposited. Optical spectroscopy results show that the transition temperature between Form I (room temperature phase) and Form II (high temperature phase) depends on the film thickness, and that Form I can also be strain-stabilized up to 135 °C.

Checkerboard deposition of lithium manganese oxide spinel (LiMn2O4) by RF magnetron sputtering on a stainless steel in all-solid-state thin film battery

Science.gov (United States)

Hsueh, T. H.; Yu, Y. Q.; Jan, D. J.; Su, C. H.; Chang, S. M.

2018-03-01

All-solid-state thin film lithium batteries (TFLBs) are the most competitive low-power sources to be applied in various kinds of micro-electro-mechanical systems and have been draw a lot of attention in academic research. In this paper, the checkerboard deposition of all-solid-state TFLB was composed of thin film lithium metal anode, lithium phosphorus oxynitride (LiPON) solid electrolyte, and checkerboard deposition of lithium manganese oxide spinel (LiMn2O4) cathode. The LiPON and LiMn2O4 were deposited by a radio frequency magnetron sputtering system, and the lithium metal was deposited by a thermal evaporation coater. The electrochemical characterization of this lithium battery showed the first discharge capacity of 107.8 μAh and the capacity retention was achieved 95.5% after 150 charge-discharge cycles between 4.3V and 3V at a current density of 11 μA/cm2 (0.5C). Obviously, the checkerboard of thin film increased the charge exchange rate; also this lithium battery exhibited high C-rate performance, with better capacity retention of 82% at 220 μA/cm2 (10C).

Tribology of thin wetting films between bubble and moving solid surface.

Science.gov (United States)

Karakashev, Stoyan I; Stöckelhuber, Klaus W; Tsekov, Roumen; Phan, Chi M; Heinrich, Gert

2014-08-01

This work shows a successful example of coupling of theory and experiment to study the tribology of bubble rubbing on solid surface. Such kind of investigation is reported for the first time in the literature. A theory about wetting film intercalated between bubble and moving solid surface was developed, thus deriving the non-linear evolution differential equation which accounted for the friction slip coefficient at the solid surface. The stationary 3D film thickness profile, which appears to be a solution of the differential equation, for each particular speed of motion of the solid surface was derived by means of special procedure and unique interferometric experimental setup. This allowed us to determine the 3D map of the lift pressure within the wetting film, the friction force per unit area and the friction coefficient of rubbing at different speeds of motion of the solid surface. Thus, we observed interesting tribological details about the rubbing of the bubble on the solid surface like for example: 1. A regime of mixed friction between dry and lubricated friction exists in the range of 6-170 μm/s, beyond which the rubbing between the bubble and solid becomes completely lubricated and passes through the maximum; 2. The friction coefficient of rubbing has high values at very small speeds of solid's motion and reduces substantially with the increase of the speed of the solid motion until reaching small values, which change insignificantly with the further increase of the speed of the solid. Despite the numerous studies on the motion of bubble/droplet in close proximity to solid wall in the literature, the present investigation appears to be a step ahead in this area as far as we were able to derive 3D maps of the bubble close to the solid surface, which makes the investigation more profound. © 2013.

Specific considerations for obtaining appropriate La1-xSrxGa1-yMgyO3-δ thin films using pulsed-laser deposition and its influence on the performance of solid-oxide fuel cells

Science.gov (United States)

Hwang, Jaeyeon; Lee, Heon; Lee, Jong-Ho; Yoon, Kyung Joong; Kim, Hyoungchul; Hong, Jongsup; Son, Ji-Won

2015-01-01

To obtain La1-xSrxGa1-yMgyO3-δ (LSGM) thin films with the appropriate properties, pulsed-laser deposition (PLD) is employed, and specific considerations regarding control of the deposition parameters is investigated. It is demonstrated that with a target of stoichiometric composition, appropriate LSGM thin films cannot be produced because of the deviation of the composition from the target to the thin film. Only after adjusting the target composition an LSGM thin film with an appropriate composition and phase can be obtained. The optimized LSGM thin film possesses an electrical conductivity close to that of the bulk LSGM. In contrast, non-optimized thin films do not yield any measurable electrical conductivity. The impact of the optimization of the LSGM thin-film electrolyte on the cell performance is quite significant, in that a solid-oxide fuel cell (SOFC) with an optimized LSGM thin-film electrolyte produces a maximum power density of 1.1 W cm-2 at 600 °C, whereas an SOFC with a non-optimal LSGM thin-film electrolyte is not operable.

Epitaxially influenced boundary layer model for size effect in thin metallic films

International Nuclear Information System (INIS)

Bazant, Zdenek P.; Guo Zaoyang; Espinosa, Horacio D.; Zhu Yong; Peng Bei

2005-01-01

It is shown that the size effect recently observed by Espinosa et al., [J. Mech. Phys. Solids51, 47 (2003)] in pure tension tests on free thin metallic films can be explained by the existence of a boundary layer of fixed thickness, located at the surface of the film that was attached onto the substrate during deposition. The boundary layer is influenced by the epitaxial effects of crystal growth on the dislocation density and texture (manifested by prevalent crystal plane orientations). This influence is assumed to cause significantly elevated yield strength. Furthermore, the observed gradual postpeak softening, along with its size independence, which is observed in short film strips subjected to pure tension, is explained by slip localization, originating at notch-like defects, and by damage, which can propagate in a stable manner when the film strip under pure tension is sufficiently thin and short. For general applications, the present epitaxially influenced boundary layer model may be combined with the classical strain-gradient plasticity proposed by Gao et al., [J. Mech. Phys. Solids 47, 1239 (1999)], and it is shown that this combination is necessary to fit the test data on both pure tension and bending of thin films by one and the same theory. To deal with films having different crystal grain sizes, the Hall-Petch relation for the yield strength dependence on the grain size needs to be incorporated into the combined theory. For very thin films, in which a flattened grain fills the whole film thickness, the Hall-Petch relation needs a cutoff, and the asymptotic increase of yield strength with diminishing film thickness is then described by the extension of Nix's model of misfit dislocations by Zhang and Zhou [J. Adv. Mater. 38, 51 (2002)]. The final result is a proposal of a general theory for strength, size effect, hardening, and softening of thin metallic films

Epitaxially influenced boundary layer model for size effect in thin metallic films

Science.gov (United States)

Bažant, Zdeněk P.; Guo, Zaoyang; Espinosa, Horacio D.; Zhu, Yong; Peng, Bei

2005-04-01

It is shown that the size effect recently observed by Espinosa et al., [J. Mech. Phys. Solids51, 47 (2003)] in pure tension tests on free thin metallic films can be explained by the existence of a boundary layer of fixed thickness, located at the surface of the film that was attached onto the substrate during deposition. The boundary layer is influenced by the epitaxial effects of crystal growth on the dislocation density and texture (manifested by prevalent crystal plane orientations). This influence is assumed to cause significantly elevated yield strength. Furthermore, the observed gradual postpeak softening, along with its size independence, which is observed in short film strips subjected to pure tension, is explained by slip localization, originating at notch-like defects, and by damage, which can propagate in a stable manner when the film strip under pure tension is sufficiently thin and short. For general applications, the present epitaxially influenced boundary layer model may be combined with the classical strain-gradient plasticity proposed by Gao et al., [J. Mech. Phys. Solids 47, 1239 (1999)], and it is shown that this combination is necessary to fit the test data on both pure tension and bending of thin films by one and the same theory. To deal with films having different crystal grain sizes, the Hall-Petch relation for the yield strength dependence on the grain size needs to be incorporated into the combined theory. For very thin films, in which a flattened grain fills the whole film thickness, the Hall-Petch relation needs a cutoff, and the asymptotic increase of yield strength with diminishing film thickness is then described by the extension of Nix's model of misfit dislocations by Zhang and Zhou [J. Adv. Mater. 38, 51 (2002)]. The final result is a proposal of a general theory for strength, size effect, hardening, and softening of thin metallic films.

Chalcogenide phase-change thin films used as grayscale photolithography materials.

Science.gov (United States)

Wang, Rui; Wei, Jingsong; Fan, Yongtao

2014-03-10

Chalcogenide phase-change thin films are used in many fields, such as optical information storage and solid-state memory. In this work, we present another application of chalcogenide phase-change thin films, i.e., as grayscale photolithgraphy materials. The grayscale patterns can be directly inscribed on the chalcogenide phase-change thin films by a single process through direct laser writing method. In grayscale photolithography, the laser pulse can induce the formation of bump structure, and the bump height and size can be precisely controlled by changing laser energy. Bumps with different height and size present different optical reflection and transmission spectra, leading to the different gray levels. For example, the continuous-tone grayscale images of lifelike bird and cat are successfully inscribed onto Sb(2)Te(3) chalcogenide phase-change thin films using a home-built laser direct writer, where the expression and appearance of the lifelike bird and cat are fully presented. This work provides a way to fabricate complicated grayscale patterns using laser-induced bump structures onto chalcogenide phase-change thin films, different from current techniques such as photolithography, electron beam lithography, and focused ion beam lithography. The ability to form grayscale patterns of chalcogenide phase-change thin films reveals many potential applications in high-resolution optical images for micro/nano image storage, microartworks, and grayscale photomasks.

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.

Thin and flexible all-solid supercapacitor prepared from novel single wall carbon nanotubes/polyaniline thin films obtained in liquid-liquid interfaces

Science.gov (United States)

de Souza, Victor Hugo Rodrigues; Oliveira, Marcela Mohallem; Zarbin, Aldo José Gorgatti

2014-08-01

The present work describes for the first time the synthesis and characterization of single wall carbon nanotubes/polyaniline (SWNTs/PAni) nanocomposite thin films in a liquid-liquid interface, as well as the subsequent construction of a flexible all-solid supercapacitor. Different SWNTs/PAni nanocomposites were prepared by varying the ratio of SWNT to aniline, and the samples were characterized by scanning and transmission electron microscopy, Raman and UV-Vis spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. The pseudo-capacitive behavior of the nanocomposites was evaluated by charge/discharge galvanostatic measurements. The presence of the SWNTs affected the electronic and vibrational properties of the polyaniline and also improved the pseudo-capacitive behavior of the conducting polymer. A very thin and flexible all-solid device was manufactured using two electrodes (polyethylene terephthalate-PET covered with the SWNT/PAni nanocomposite separated by a H2SO4-PVA gel electrolyte). The pseudo-capacitive behavior was characterized by a volumetric specific capacitance of approximately 76.7 F cm-3, even under mechanical deformation, indicating that this nanocomposite has considerable potential for application in new-generation energy storage devices.

An in-situ chemical reaction deposition of nanosized wurtzite CdS thin films

International Nuclear Information System (INIS)

Chu Juan; Jin Zhengguo; Cai Shu; Yang Jingxia; Hong Zhanglian

2012-01-01

Nanocrystalline CdS thin films were deposited on glass substrates by an ammonia-free in-situ chemical reaction synthesis technique using cadmium cationic precursor solid films as reaction source and sodium sulfide based solutions as anionic reaction medium. Effects of ethanolamine addition to the cadmium cationic precursor solid films, deposition cycle numbers and annealing treatments in Ar atmosphere on structure, morphology, chemical composition and optical properties of the resultant films were investigated by X-ray diffraction, field emission scanning electron microscope, energy dispersive X-ray analysis and UV–Vis spectra measurements. The results show that CdS thin films deposited by the in-situ chemical reaction synthesis have wurtzite structure with (002) plane preferential orientation and crystallite size is in the range of 16 nm–19 nm. The growth of film thickness is almost constant with deposition cycle numbers and about 96 nm per cycle.

a Brief Survey on Basic Properties of Thin Films for Device Application

Science.gov (United States)

Rao, M. C.; Shekhawat, M. S.

Thin film materials are the key elements of continued technological advances made in the fields of optoelectronic, photonic and magnetic devices. Thin film studies have directly or indirectly advanced many new areas of research in solid state physics and chemistry which are based on phenomena uniquely characteristic of the thickness, geometry and structure of the film. The processing of materials into thin films allows easy integration into various types of devices. Thin films are extremely thermally stable and reasonably hard, but they are fragile. On the other hand organic materials have reasonable thermal stability and are tough, but are soft. Thin film mechanical properties can be measured by tensile testing of freestanding films and by the micro beam cantilever deflection technique, but the easiest way is by means of nanoindentation. Optical experiments provide a good way of examining the properties of semiconductors. Particularly measuring the absorption coefficient for various energies gives information about the band gaps of the material. Thin film materials have been used in semiconductor devices, wireless communications, telecommunications, integrated circuits, rectifiers, transistors, solar cells, light-emitting diodes, photoconductors and light crystal displays, lithography, micro- electromechanical systems (MEMS) and multifunctional emerging coatings, as well as other emerging cutting technologies.

Determination and analysis of dispersive optical constants of some organic thin films

International Nuclear Information System (INIS)

Kaya, Y.; Taysioglu, A. A.; Peksoez, A.; Irez, G.; Derebasi, N.; Kaynak, G.

2010-01-01

Schiff bases are an important class of ligands in coordination chemistry and find extensive application in different fields. Recently, increased interest in organic thin film materials has arisen due to their extensive applications in the fields of mechanics, flexible electronics and optics. Optoelectronics is the area in which organic films and organic-inorganic nanostructures have found their main applications in the last decade. These organic thin films have been also used in a wide variety of applications such as Schottky diodes, solid state devices and optical sensors. The optical constants (refractive index, n; extinction coefficient, k and dielectric constant, e) of some organic thin films were determined using reflectance and transmittance spectra. Analysis of the basis absorption spectra was also carried out to determine optical band gap (Eg) and Urbach parameter (E0). A surface observation of these thin films was also carried out by an Atomic Force Microscope.

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

Sorptive thin film microextraction followed by direct solid state spectrofluorimetry: A simple, rapid and sensitive method for determination of carvedilol in human plasma.

Science.gov (United States)

Karimi, Shima; Talebpour, Zahra; Adib, Noushin

2016-06-14

A poly acrylate-ethylene glycol (PA-EG) thin film is introduced for the first time as a novel polar sorbent for sorptive extraction method coupled directly to solid-state spectrofluorimetry without the necessity of a desorption step. The structure, polarity, fluorescence property and extraction performance of the developed thin film were investigated systematically. Carvedilol was used as the model analyte to evaluate the proposed method. The entire procedure involved one-step extraction of carvedilol from plasma using PA-EG thin film sorptive phase without protein precipitation. Extraction variables were studied in order to establish the best experimental conditions. Optimum extraction conditions were the followings: stirring speed of 1000 rpm, pH of 6.8, extraction temperature of 60 °C, and extraction time of 60 min. Under optimal conditions, extraction of carvedilol was carried out in spiked human plasma; and the linear range of calibration curve was 15-300 ng mL(-1) with regression coefficient of 0.998. Limit of detection (LOD) for the method was 4.5 ng mL(-1). The intra- and inter-day accuracy and precision of the proposed method were evaluated in plasma sample spiked with three concentration levels of carvedilol; yielding a recovery of 91-112% and relative standard deviation of less than 8%, respectively. The established procedure was successfully applied for quantification of carvedilol in plasma sample of a volunteer patient. The developed PA-EG thin film sorptive phase followed by solid-state spectrofluorimetric method provides a simple, rapid and sensitive approach for the analysis of carvedilol in human plasma. Copyright © 2016 Elsevier B.V. All rights reserved.

Thin-film silicon solar cell technology

Czech Academy of Sciences Publication Activity Database

Shah, A. V.; Schade, H.; Vaněček, Milan; Meier, J.; Vallat-Sauvain, E.; Wyrsch, N.; Kroll, U.; Droz, C.; Bailat, J.

2004-01-01

Roč. 12, - (2004), s. 113-142 ISSN 1062-7995 R&D Projects: GA MŽP SN/320/11/03 Institutional research plan: CEZ:AV0Z1010914 Keywords : thin-film silicon modules * hydrogenerated amorphous silicon(a-Si:H) * hydrogenerated microcrystalline (ćc-Si:H) * transparent conductive oxydes(TCOs) * building-integrated photovoltaics(BIPV) Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.196, year: 2004

Dielectric and acoustical high frequency characterisation of PZT thin films

International Nuclear Information System (INIS)

Conde, Janine; Muralt, Paul

2010-01-01

Pb(Zr, Ti)O 3 (PZT) is an interesting material for bulk acoustic wave resonator applications due to its high electromechanical coupling constant, which would enable fabrication of large bandwidth frequency filters. The major challenge of the PZT solid solution system is to overcome mechanical losses generally observed in PZT ceramics. To increase the understanding of these losses in textured thin films, thin film bulk acoustic resonators (TFBAR's) based on PZT thin films with compositions either in the tetragonal region or at the morphotropic phase boundary and (111) or {100} textures were fabricated and studied up to 2 GHz. The dielectric and elastic materials coefficients were extracted from impedance measurements at the resonance frequency. The dispersion of the dielectric constant was obtained from impedance measurements up to 2 GHz. The films with varying compositions, textures and deposition methods (sol-gel or sputtering) were compared in terms of dielectric and acoustical properties.

Dielectric and acoustical high frequency characterisation of PZT thin films

Science.gov (United States)

Conde, Janine; Muralt, Paul

2010-02-01

Pb(Zr, Ti)O3 (PZT) is an interesting material for bulk acoustic wave resonator applications due to its high electromechanical coupling constant, which would enable fabrication of large bandwidth frequency filters. The major challenge of the PZT solid solution system is to overcome mechanical losses generally observed in PZT ceramics. To increase the understanding of these losses in textured thin films, thin film bulk acoustic resonators (TFBAR's) based on PZT thin films with compositions either in the tetragonal region or at the morphotropic phase boundary and (111) or {100} textures were fabricated and studied up to 2 GHz. The dielectric and elastic materials coefficients were extracted from impedance measurements at the resonance frequency. The dispersion of the dielectric constant was obtained from impedance measurements up to 2 GHz. The films with varying compositions, textures and deposition methods (sol-gel or sputtering) were compared in terms of dielectric and acoustical properties.

Thin-film calorimetry. In-situ characterization of materials for lithium-ion batteries

Energy Technology Data Exchange (ETDEWEB)

Omelcenko, Alexander; Wulfmeier, Hendrik; Albrecht, Daniel; Fritze, Holger [Clausthal Univ. of Technology, Goslar (Germany). Inst. of Energy Research and Physical Technologies; El Mofid, Wassima; Ivanov, Svetlozar; Bund, Andreas [Ilmenau Univ. of Technology (Germany). Dept. of Electrochemistry

2017-11-15

Thin-film calorimetry allows for qualitative and quantitative in-situ analysis of thermodynamic properties of thin films and thin-film systems from room temperature up to 1000 C. It is based on highly sensitive piezoelectric langasite resonators which serve simultaneously as planar temperature sensors and substrates for the films of interest. Generation or consumption of heat during phase transformations of the films cause deviations from the regular course of the resonance frequency. Thermodynamic data such as phase transformation temperatures and enthalpies are extracted from these deviations. Thin-film calorimetry on Sn and Al thin films is performed to prove the concept. The results demonstrate high reproducibility of the measurement approach and are in agreement with literature data obtained by established calorimetric techniques. The calibration of the system is done in different atmospheres by application of defined heat pulses via heating structures. The latter replace the films of interest and simulate phase transformations to provide detailed analysis of the heat transfer mechanisms occurring in the measurement system. Based on this analysis, a data evaluation concept is developed. Application-relevant studies are performed on thin films of the lithium-ion battery materials NMC(A), NCA, LMO, and MoS{sub 2}. Their phase transformation temperatures and enthalpies are evaluated in oxidizing and reducing atmospheres. Furthermore, their thermodynamic stability ranges are presented. Finally, measurements on all-solid-state thin-film batteries during electrochemical cycling are performed. They demonstrate the suitability of the system for in-situ investigations.

Thermo-optic characteristic of DNA thin solid film and its application as a biocompatible optical fiber temperature sensor.

Science.gov (United States)

Hong, Seongjin; Jung, Woohyun; Nazari, Tavakol; Song, Sanggwon; Kim, Taeoh; Quan, Chai; Oh, Kyunghwan

2017-05-15

We report unique thermo-optical characteristics of DNA-Cetyl tri-methyl ammonium (DNA-CTMA) thin solid film with a large negative thermo-optical coefficient of -3.4×10-4/°C in the temperature range from 20°C to 70°C without any observable thermal hysteresis. By combining this thermo-optic DNA film and fiber optic multimode interference (MMI) device, we experimentally demonstrated a highly sensitive compact temperature sensor with a large spectral shift of 0.15 nm/°C. The fiber optic MMI device was a concatenated structure with single-mode fiber (SMF)-coreless silica fiber (CSF)-single mode fiber (SMF) and the DNA-CTMA film was deposited on the CSF. The spectral shifts of the device in experiments were compared with the beam propagation method, which showed a good agreement.

NMR characterization of thin films

Science.gov (United States)

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

2010-06-15

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

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.

Growth of Hexagonal Columnar Nanograin Structured SiC Thin Films on Silicon Substrates with Graphene–Graphitic Carbon Nanoflakes Templates from Solid Carbon Sources

Directory of Open Access Journals (Sweden)

Wanshun Zhao

2013-04-01

Full Text Available We report a new method for growing hexagonal columnar nanograin structured silicon carbide (SiC thin films on silicon substrates by using graphene–graphitic carbon nanoflakes (GGNs templates from solid carbon sources. The growth was carried out in a conventional low pressure chemical vapor deposition system (LPCVD. The GGNs are small plates with lateral sizes of around 100 nm and overlap each other, and are made up of nanosized multilayer graphene and graphitic carbon matrix (GCM. Long and straight SiC nanograins with hexagonal shapes, and with lateral sizes of around 200–400 nm are synthesized on the GGNs, which form compact SiC thin films.

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.

Utilizing thin-film solid-phase extraction to assess the effect of organic carbon amendments on the bioavailability of DDT and dieldrin to earthworms

Science.gov (United States)

Improved approaches are needed to rapidly and accurately assess the bioavailability of persistent, hydrophobic organic compounds in soils at contaminated sites. The performance of a thin-film solid-phase extraction (TF-SPE) assay using vials coated with ethylene vinyl acetate polymer was compared to...

Solid-state dewetting of single- and bilayer Au-W thin films: Unraveling the role of individual layer thickness, stacking sequence and oxidation on morphology evolution

Directory of Open Access Journals (Sweden)

A. Herz

2016-03-01

Full Text Available Self-assembly of ultrathin Au, W, and Au-W bilayer thin films is investigated using a rapid thermal annealing technique in an inert ambient. The solid-state dewetting of Au films is briefly revisited in order to emphasize the role of initial film thickness. W films deposited onto SiO2 evolve into needle-like nanocrystals rather than forming particle-like agglomerates upon annealing at elevated temperatures. Transmission electron microscopy reveals that such nanocrystals actually consist of tungsten (VI oxide (WO3 which is related to an anisotropic oxide crystal growth out of the thin film. The evolution of W films is highly sensitive to the presence of any residual oxygen. Combination of both the dewetting of Au and the oxide crystal growth of WO3 is realized by using various bilayer film configurations of the immiscible Au and W. At low temperature, Au dewetting is initiated while oxide crystal growth is still suppressed. Depending on the stacking sequence of the Au-W bilayer thin film, W acts either as a substrate or as a passivation layer for the dewetting of Au. Being the ground layer, W changes the wettability of Au which clearly modifies its initial state for the dewetting. Being the top layer, W prevents Au from dewetting regardless of Au film thickness. Moreover, regular pattern formation of Au-WO3 nanoparticles is observed at high temperature demonstrating how bilayer thin film dewetting can create unique nanostructure arrangements.

Solid-state dewetting of single- and bilayer Au-W thin films: Unraveling the role of individual layer thickness, stacking sequence and oxidation on morphology evolution

Energy Technology Data Exchange (ETDEWEB)

Herz, A., E-mail: andreas.herz@tu-ilmenau.de, E-mail: dong.wang@tu-ilmenau.de; Franz, A.; Theska, F.; Hentschel, M.; Kups, Th.; Wang, D., E-mail: andreas.herz@tu-ilmenau.de, E-mail: dong.wang@tu-ilmenau.de; Schaaf, P. [Department of Materials for Electronics and Electrical Engineering, Institute of Materials Science and Engineering and Institute of Micro- and Nanotechnologies MacroNano, TU Ilmenau, D-98693 Ilmenau (Germany)

2016-03-15

Self-assembly of ultrathin Au, W, and Au-W bilayer thin films is investigated using a rapid thermal annealing technique in an inert ambient. The solid-state dewetting of Au films is briefly revisited in order to emphasize the role of initial film thickness. W films deposited onto SiO{sub 2} evolve into needle-like nanocrystals rather than forming particle-like agglomerates upon annealing at elevated temperatures. Transmission electron microscopy reveals that such nanocrystals actually consist of tungsten (VI) oxide (WO{sub 3}) which is related to an anisotropic oxide crystal growth out of the thin film. The evolution of W films is highly sensitive to the presence of any residual oxygen. Combination of both the dewetting of Au and the oxide crystal growth of WO{sub 3} is realized by using various bilayer film configurations of the immiscible Au and W. At low temperature, Au dewetting is initiated while oxide crystal growth is still suppressed. Depending on the stacking sequence of the Au-W bilayer thin film, W acts either as a substrate or as a passivation layer for the dewetting of Au. Being the ground layer, W changes the wettability of Au which clearly modifies its initial state for the dewetting. Being the top layer, W prevents Au from dewetting regardless of Au film thickness. Moreover, regular pattern formation of Au-WO{sub 3} nanoparticles is observed at high temperature demonstrating how bilayer thin film dewetting can create unique nanostructure arrangements.

Optical refraction index and polarization profile of ferroelectric thin films

Czech Academy of Sciences Publication Activity Database

Glinchuk, M. D.; Eliseev, E. A.; Deineka, Alexander; Jastrabík, Lubomír; Suchaneck, G.; Sandner, T.; Gerlach, G.; Hrabovský, Miroslav

2001-01-01

Roč. 38, 1-4 (2001), s. 101-110 ISSN 1058-4587 R&D Projects: GA MŠk LN00A015; GA ČR GA202/00/1425 Institutional research plan: CEZ:AV0Z1010914 Keywords : thin film * refraction index * polarization * film thickness Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.512, year: 2001

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.

Thin-film solar cells

International Nuclear Information System (INIS)

Aberle, Armin G.

2009-01-01

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

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

International Nuclear Information System (INIS)

Watanabe, S.

1984-01-01

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

Thin film galvanic cell with RbAg4I5 solid electrolyte

International Nuclear Information System (INIS)

Bodnaruk, L.I.; Danilov, A.V.; Kulinkovich, V.E.; Aleskovskij, V.B.

1975-01-01

In order to decrease the size and weight and to increase the specific capacity and energy of galvanic cells, some solid electrolytes in the form of thin films are proposed. The galvanic cells were prepared by a combined method: the cathodic and anodic materials (Te and Ag) were evaporated under vacuo to cover an electrolyte layer, the latter being obtained by impregnating the porous materials with RbAg 4 I 5 acetonic solution. The most specific charge curves of the galvanic cells at various current densities are given: specific energy of the samples was 0.2 to 0.7 watt-h/kg, their capacity being 0.1 to 0.2 mah. Behaviour of the cells when stored (that of Ag(RbAg 4 I 5 ) interface in particular) was investigated, namely, the effect of the storage time on the capacity and internal resistance of the galvanic cell

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

International Nuclear Information System (INIS)

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

1992-01-01

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

Thin films of molecular materials synthesized from fisher's carbene ferrocenyl: Film formation and electrical properties

Energy Technology Data Exchange (ETDEWEB)

Sanchez-Vergara, M.E. [Coordinacion de Ingenieria Mecatronica. Escuela de Ingenieria, Universidad Anahuac del Norte. Avenida Lomas de la Anahuac s/n, Col. Lomas Anahuac, 52786, Huixquilucan (Mexico)], E-mail: elena.sanchez@anahuac.mx; Ortiz, A. [Instituto de Investigaciones en Materiales. Universidad Nacional Autonoma de Mexico. A. P. 70-360, 04510, Mexico, DF (Mexico); Alvarez-Toledano, C.; Moreno, A. [Instituto de Quimica, Universidad Nacional Autonoma de Mexico. Circuito Exterior, Ciudad Universitaria, 04510, Mexico, DF (Mexico); Alvarez, J.R. [Instituto Tecnologico y de Estudios Superiores de Monterrey, Campus Ciudad de Mexico. Calle del Puente 222, Col. Ejidos de Huipulco, 14380, Mexico, DF (Mexico)

2008-07-31

The synthesis of materials from Fisher's carbene ferrocenyl of the elements chromium, molybdenum and tungsten was carried out. The Fisher's compounds that were synthesized included the following combinations of two different metallic atoms: iron with chromium, iron with molybdenum and iron with tungsten. The molecular solids' preparation was done in electro-synthesis cells with platinum electrodes. Thin films were prepared by vacuum thermal evaporation on quartz substrates and crystalline silicon wafers. Pellets and thin films from these compounds were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive spectroscopy, atomic force microscopy and ellipsometry. The powder and thin films synthesized from these materials show the same intra-molecular bonds shown by infrared spectroscopy results, suggesting that thermal evaporation does not alter these bonds in spite of the thin films being amorphous, in contrast with other bimetallic complexes where material decomposition occurs. The differences in the conductivity values of the prepared films are very small, so they may be attributed to the different metallic ions employed in each case. The tungsten complex exhibits a higher conductivity than the molybdenum and chromium complexes at room temperature. Electrical conductivity values found for thin films are higher than for pellets made of the same molecular materials.

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.

Dielectric and acoustical high frequency characterisation of PZT thin films

Energy Technology Data Exchange (ETDEWEB)

Conde, Janine; Muralt, Paul, E-mail: janine.conde@epfl.ch [Department of Materials Science, EPFL (Switzerland)

2010-02-15

Pb(Zr, Ti)O{sub 3} (PZT) is an interesting material for bulk acoustic wave resonator applications due to its high electromechanical coupling constant, which would enable fabrication of large bandwidth frequency filters. The major challenge of the PZT solid solution system is to overcome mechanical losses generally observed in PZT ceramics. To increase the understanding of these losses in textured thin films, thin film bulk acoustic resonators (TFBAR's) based on PZT thin films with compositions either in the tetragonal region or at the morphotropic phase boundary and (111) or {l_brace}100{r_brace} textures were fabricated and studied up to 2 GHz. The dielectric and elastic materials coefficients were extracted from impedance measurements at the resonance frequency. The dispersion of the dielectric constant was obtained from impedance measurements up to 2 GHz. The films with varying compositions, textures and deposition methods (sol-gel or sputtering) were compared in terms of dielectric and acoustical properties.

First report on synthesis of ZnFe_2O_4 thin film using successive ionic layer adsorption and reaction: Approach towards solid-state symmetric supercapacitor device

International Nuclear Information System (INIS)

Raut, Shrikant S.; Sankapal, Babasaheb R.

2016-01-01

Highlights: • First report on synthesis of ZnFe_2O_4 thin film using SILAR method. • ZnFe_2O_4 electrode yields the specific capacitance of 471 Fg"−"1 at a scan rate of 5 mV s"−"1 in 1 M NaOH aqueous solution. • Solid-state symmetric supercapacitor device based on ZnFe_2O_4 sandwiched in polyvinyl alcohol (PVA)–LiClO_4 gel electrolyte exhibits voltage windows of 1.0 V. • ZnFe_2O_4-SSS supercapacitor device shows good energy and power density with long cycle life. - Abstract: ZnFe_2O_4 thin film has been synthesized by a simple and low cost successive ionic layer adsorption and reaction (SILAR) method without the use of surfactant or template. The nanoplate composed of nanoparticles with porous surface morphology has been revealed which is beneficial towards supercapacitor application. Formed ZnFe_2O_4 thin film has been tested as an electrode material for supercapacitor through electrochemical analysis. First attempt for SILAR synthesized ZnFe_2O_4 thin film exhibited a specific capacitance of 471 Fg"−"1 at a scan rate of 5 mVs"−"1 in 1 M NaOH aqueous solution. Further, ZnFe_2O_4 solid-state symmetric (SSS) supercapacitor device demonstrated voltage window of 1.0 V with specific capacitance of 32 Fg"−"1, energy density of 4.47 Whkg"−"1 and power density of 277 Wkg"−"1 at 1 Ag"−"1 current density. Such high performance capacitive behavior indicates ZnFe_2O_4 thin film is promising and low cost electrode material towards energy storage devices for various portable electronic systems.

Supercritical fluid molecular spray thin films and fine powders

Science.gov (United States)

Smith, Richard D.

1988-01-01

Solid films are deposited, or fine powders formed, by dissolving a solid material into a supercritical fluid solution at an elevated pressure and then rapidly expanding the solution through a short orifice into a region of relatively low pressure. This produces a molecular spray which is directed against a substrate to deposit a solid thin film thereon, or discharged into a collection chamber to collect a fine powder. The solvent is vaporized and pumped away. Solution pressure is varied to determine, together with flow rate, the rate of deposition and to control in part whether a film or powder is produced and the granularity of each. Solution temperature is varied in relation to formation of a two-phase system during expansion to control porosity of the film or powder. A wide variety of film textures and powder shapes are produced of both organic and inorganic compounds. Films are produced with regular textural feature dimensions of 1.0-2.0 .mu.m down to a range of 0.01 to 0.1 .mu.m. Powders are formed in very narrow size distributions, with average sizes in the range of 0.02 to 5 .mu.m.

Bioplasmonic Alloyed Nanoislands Using Dewetting of Bilayer Thin Films.

Science.gov (United States)

Kang, Minhee; Ahn, Myeong-Su; Lee, Youngseop; Jeong, Ki-Hun

2017-10-25

Unlike monometallic materials, bimetallic plasmonic materials offer extensive benefits such as broadband tuning capability or high environmental stability. Here we report a broad range tuning of plasmon resonance of alloyed nanoislands by using solid-state dewetting of gold and silver bilayer thin films. Thermal dewetting after successive thermal evaporation of thin metal double-layer films readily forms AuAg-alloyed nanoislands with a precise composition ratio. The complete miscibility of alloyed nanoislands results in programmable tuning of plasmon resonance wavelength in a broadband visible range. Such extraordinary tuning capability opens up a new direction for plasmonic enhancement in biophotonic applications such as surface-enhanced Raman scattering or plasmon-enhanced fluorescence.

Thickness determination of thin solid films by angle-resolved X-ray fluorescence spectrometry using monochromatized synchrotron radiation

Science.gov (United States)

Schmitt, W.; Drotbohm, P.; Rothe, J.; Hormes, J.; Ottermann, C. R.; Bange, K.

1995-05-01

Thickness measurements by the method of angle-resolved, self-ratio X-ray fluorescence spectrometry (AR/SR/XFS) have been carried out on thin solid films using monochromatized synchrotron radiation at the Bonn storage ring ELSA. Synchrotron radiation was monochromatized by means of a double-crystal monochromator and fluorescence radiation was detected by a Si(Li) semiconductor detector. The results for sample systems consisting of Au on Si, Cr on SiO2 and TiO2 on alkali-free glass are very satisfactory and agree well with results obtained by other methods.

Synthesis and characterization of Cu–Al–Ni shape memory alloy multilayer thin films

International Nuclear Information System (INIS)

Gómez-Cortés, J.F.; San Juan, J.; López, G.A.; Nó, M.L.

2013-01-01

Among active materials, shape memory alloys are well recognized for their work output density. Because of that, these alloys have attracted much attention to be used in micro/nano electromechanical systems. In the present work, the electron beam evaporation technique has been used to growth, by a multilayer method, two shape memory alloy thin films with different Cu–Al–Ni composition. Multilayers have been further thermally treated to produce the alloys by solid solution diffusion. The produced multilayers have been characterized and the presence of the martensite phase in the obtained thin films was studied. Furthermore, the influence of two different coatings onto the Si substrates, namely Si/SiO 2 and Si/Si 3 N 4 , was investigated. Mechanically stable, not detaching from the substrates, Cu–Al–Ni shape memory alloy thin films, about 1 micrometre thick, showing a martensitic transformation have been produced. - Highlights: ► Multilayer thin films of Cu–Al–Ni shape memory alloys produced by e-beam evaporation. ► SiN X 200 nm thick coating is good for high quality Cu–Al–Ni shape memory thin films. ► Thermal treatment renders Cu–Al–Ni multilayer in homogeneous martensite thin film

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

International Nuclear Information System (INIS)

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

2007-01-01

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

In-situ investigation of thermal instabilities and solid state dewetting in polycrystalline platinum thin films via confocal laser microscopy

Energy Technology Data Exchange (ETDEWEB)

Jahangir, S.; Cheng, Xuan; Huang, H. H.; Nagarajan, V. [School of Materials Science and Engineering, University of New South Wales, Sydney 2052 (Australia); Ihlefeld, J. [Electronic, Optical, and Nanomaterials Department, Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

2014-10-28

Solid state dewetting and the subsequent morphological changes for platinum thin films grown on zinc oxide (ZnO) buffered (001) silicon substrates (Pt/ZnO/SiO{sub 2}/(001)Si system) is investigated under vacuum conditions via a custom-designed confocal laser microscope coupled with a laser heating system. Live imaging of thin film dewetting under a range of heating and quenching vacuum ambients reveals events including hillock formation, hole formation, and hole growth that lead to formation of a network of Pt ligaments, break up of Pt ligaments to individual islands and subsequent Pt islands shape reformation, in chronological fashion. These findings are corroborated by ex-situ materials characterization and quantitative electron microscopy analysis. A secondary hole formation via blistering before film rupture is revealed to be the critical stage, after which a rapid dewetting catastrophe occurs. This process is instantaneous and cannot be captured by ex-situ methods. Finally, an intermetallic phase forms at 900 °C and alters the morphology of Pt islands, suggesting a practical limit to the thermal environments that may be used for these platinized silicon wafers in vacuum conditions.

In-situ investigation of thermal instabilities and solid state dewetting in polycrystalline platinum thin films via confocal laser microscopy

International Nuclear Information System (INIS)

Jahangir, S.; Cheng, Xuan; Huang, H. H.; Nagarajan, V.; Ihlefeld, J.

2014-01-01

Solid state dewetting and the subsequent morphological changes for platinum thin films grown on zinc oxide (ZnO) buffered (001) silicon substrates (Pt/ZnO/SiO 2 /(001)Si system) is investigated under vacuum conditions via a custom-designed confocal laser microscope coupled with a laser heating system. Live imaging of thin film dewetting under a range of heating and quenching vacuum ambients reveals events including hillock formation, hole formation, and hole growth that lead to formation of a network of Pt ligaments, break up of Pt ligaments to individual islands and subsequent Pt islands shape reformation, in chronological fashion. These findings are corroborated by ex-situ materials characterization and quantitative electron microscopy analysis. A secondary hole formation via blistering before film rupture is revealed to be the critical stage, after which a rapid dewetting catastrophe occurs. This process is instantaneous and cannot be captured by ex-situ methods. Finally, an intermetallic phase forms at 900 °C and alters the morphology of Pt islands, suggesting a practical limit to the thermal environments that may be used for these platinized silicon wafers in vacuum conditions.

The evolution of droplet impacting on thin liquid film at superhydrophilic surface

Science.gov (United States)

Li, Yun; Zheng, Yi; Lan, Zhong; Xu, Wei; Ma, Xuehu

2017-12-01

Thin films are ubiquitous in nature, and the evolution of a liquid film after droplet impact is critical in many industrial processes. In this paper, a series of experiments and numerical simulations are conducted to investigate the distribution and evolution features of local temperature as the droplet impacts a thin film on the superhydrophilic surface by the thermal tracing method. A cold area is formed in the center after droplet impacts on heated solid surfaces. For the droplet impact on thin heated liquid film, a ring-shaped low temperature zone is observed in this experiment. Meanwhile, numerical simulation is adopted to analyze the mechanism and the interaction between the droplet and the liquid film. It is found that due to the vortex velocity distribution formed inside the liquid film after the impact, a large part of the droplet has congested. The heating process is not obvious in the congested area, which leads to the formation of a low-temperature area in the results.

Slippage and nanorheology of thin liquid polymer films

International Nuclear Information System (INIS)

Bäumchen, Oliver; Fetzer, Renate; Klos, Mischa; Lessel, Matthias; Marquant, Ludovic; Hähl, Hendrik; Jacobs, Karin

2012-01-01

Thin liquid films on surfaces are part of our everyday life; they serve, e.g., as coatings or lubricants. The stability of a thin layer is governed by interfacial forces, described by the effective interface potential, and has been subject of many studies in recent decades. In recent years, the dynamics of thin liquid films has come into focus since results on the reduction of the glass transition temperature raised new questions on the behavior of especially polymeric liquids in confined geometries. The new focus was fired by theoretical models that proposed significant implication of the boundary condition at the solid/liquid interface on the dynamics of dewetting and the form of a liquid front. Our study reflects these recent developments and adds new experimental data to corroborate the theoretical models. To probe the solid/liquid boundary condition experimentally, different methods are possible, each bearing advantages and disadvantages, which will be discussed. Studying liquid flow on a variety of different substrates entails a view on the direct implications of the substrate. The experimental focus of this study is the variation of the polymer chain length; the results demonstrate that inter-chain entanglements and in particular their density close to the interface, originating from non-bulk conformations, govern the liquid slip of a polymer. (paper)

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.

Improved polymer thin-film wetting behavior through nanoparticle segregation to interfaces

International Nuclear Information System (INIS)

Krishnan, R S; Mackay, M E; Duxbury, P M; Hawker, C J; Asokan, Suba; Wong, Michael S; Goyette, Rick; Thiyagarajan, P

2007-01-01

We report a systematic study of improved wetting behavior for thin polymer films containing nanoparticles, as a function of nanoparticle size and concentration, the energy of the substrate and the dielectric properties of the nanoparticles. An enthalpy matched system consisting of polystyrene nanoparticles in linear polystyrene is used to show that nanoparticles are uniformly distributed in the film after spin coating and drying. However, on annealing the film above its bulk glass transition temperature these nanoparticles segregate strongly to the solid substrate. We find that for a wide range of film thicknesses and nanoparticle sizes, a substrate coverage of nanoparticles of approximately a monolayer is required for dewetting inhibition. Cadmium selenide quantum dots also inhibit dewetting of polystyrene thin films, again when a monolayer is present. Moreover, TEM microscopy images indicate that CdSe quantum dots segregate primarily to the air interface. Theoretical interpretation of these phenomena suggests that gain of linear chain configurational entropy promotes segregation of nanoparticles to the solid substrate, as occurs for polystyrene nanoparticles; however, for CdSe nanoparticles this is offset by surface energy or enthalpic terms which promote segregation of the nanoparticles to the air interface

Thermoanalytical study of the decomposition of yttrium trifluoroacetate thin films

International Nuclear Information System (INIS)

Eloussifi, H.; Farjas, J.; Roura, P.; Ricart, S.; Puig, T.; Obradors, X.; Dammak, M.

2013-01-01

We present the use of the thermal analysis techniques to study yttrium trifluoroacetate thin films decomposition. In situ analysis was done by means of thermogravimetry, differential thermal analysis, and evolved gas analysis. Solid residues at different stages and the final product have been characterized by X-ray diffraction and scanning electron microscopy. The thermal decomposition of yttrium trifluoroacetate thin films results in the formation of yttria and presents the same succession of intermediates than powder's decomposition, however, yttria and all intermediates but YF 3 appear at significantly lower temperatures. We also observe a dependence on the water partial pressure that was not observed in the decomposition of yttrium trifluoroacetate powders. Finally, a dependence on the substrate chemical composition is discerned. - Highlights: • Thermal decomposition of yttrium trifluoroacetate films. • Very different behavior of films with respect to powders. • Decomposition is enhanced in films. • Application of thermal analysis to chemical solution deposition synthesis of films

Cycling-induced degradation of LiCoO2 thin-film cathodes at elevated temperature

International Nuclear Information System (INIS)

Van Sluytman, J.S.; West, W.C.; Whitacre, J.F.; Alamgir, F.M.; Greenbaum, S.G.

2006-01-01

The cycle life of LiCoO 2 -based all solid-state thin-film cells has been studied at room temperature, and at elevated temperatures of 50, 100, and 150 deg. C. X-ray diffraction, as well as Raman analysis, has been used to complement the electrochemical data in examining structural and chemical changes. XRD and Raman spectroscopy data indicate that elevated temperature soaks of the thin-film batteries in the quiescent state causes no discernable changes in the LiCoO 2 cathode layer. However, when the thin-film batteries are cycled at elevated temperatures, decreases in average grain size of the LiCoO 2 film occur with dramatic concomitant charge and discharge capacity loss

Comparative Review on Thin Film Growth of Iron-Based Superconductors

Directory of Open Access Journals (Sweden)

Yoshinori Imai

2017-07-01

Full Text Available Since the discovery of the novel iron-based superconductors, both theoretical and experimental studies have been performed intensively. Because iron-based superconductors have a smaller anisotropy than high-Tc cuprates and a high superconducting transition temperature, there have been a lot of researchers working on the film fabrication of iron-based superconductors and their application. Accordingly, many novel features have been reported in the films of iron-based superconductors, for example, the fabrication of the epitaxial film with a higher Tc than bulk samples, the extraction of the metastable phase which cannot be obtained by the conventional solid state reaction, and so on. In this paper, we review the progress of research on thin film fabrications of iron-based superconductors, especially the four categories: LnFeAs(O,F (Ln = Lanthanide, AEFe2As2 (AE = Alkaline-earth metal, FeCh (Ch = Chalcogen, and FeSe monolayer. Furthermore, we focus on two important topics in thin films of iron-based superconductors; one is the substrate material for thin film growth on the iron-based superconductors, and the other is the whole phase diagram in FeSe1-xTex which can be obtained only by using film-fabrication technique.

New phenomena in epitaxial growth: solid films on quasicrystalline substrates

International Nuclear Information System (INIS)

Fournee, V; Thiel, P A

2005-01-01

An overview is given of the research conducted in the field of solid film growth on quasiperiodic surfaces. An atomistic description of quasicrystalline surfaces is presented and discussed in relation to bulk structural models. The various systems for which thin film growth has been attempted so far are reviewed. Emphasis is placed on the nucleation mechanisms of the solid films, on their growth modes in relation to the nature of the deposited metals, on the possibility of intermixing or alloying at the interface and on the epitaxial relationships at the crystal-quasicrystal interfaces. We also describe situations where the deposited elements adopt a quasiperiodic structure, which opens up the possibility of extending our understanding of the relation between quasiperiodicity and the physical properties of such structurally and chemically complex solids. (topical review)

Rupture of thin liquid films on structured surfaces.

Science.gov (United States)

Ajaev, Vladimir S; Gatapova, Elizaveta Ya; Kabov, Oleg A

2011-10-01

We investigate stability and breakup of a thin liquid film on a solid surface under the action of disjoining pressure. The solid surface is structured by parallel grooves. Air is trapped in the grooves under the liquid film. Our mathematical model takes into account the effect of slip due to the presence of menisci separating the liquid film from the air inside the grooves, the deformation of these menisci due to local variations of pressure in the liquid film, and nonuniformities of the Hamaker constant which measures the strength of disjoining pressure. Both linear stability and strongly nonlinear evolution of the film are analyzed. Surface structuring results in decrease of the fastest growing instability wavelength and the rupture time. It is shown that a simplified description of film dynamics based on the standard formula for effective slip leads to significant deviations from the behavior seen in our simulations. Self-similar decay over several orders of magnitude of the film thickness near the rupture point is observed. We also show that the presence of the grooves can lead to instability in otherwise stable films if the relative groove width is above a critical value, found as a function of disjoining pressure parameters.

Bending impact on the performance of a flexible Li4Ti5O12-based all-solid-state thin-film battery.

Science.gov (United States)

Sepúlveda, Alfonso; Speulmanns, Jan; Vereecken, Philippe M

2018-01-01

The growing demand of flexible electronic devices is increasing the requirements of their power sources. The effect of bending in thin-film batteries is still not well understood. Here, we successfully developed a high active area flexible all-solid-state battery as a model system that consists of thin-film layers of Li 4 Ti 5 O 12 , LiPON, and Lithium deposited on a novel flexible ceramic substrate. A systematic study on the bending state and performance of the battery is presented. The battery withstands bending radii of at least 14 mm achieving 70% of the theoretical capacity. Here, we reveal that convex bending has a positive effect on battery capacity showing an average increase of 5.5%, whereas concave bending decreases the capacity by 4% in contrast with recent studies. We show that the change in capacity upon bending may well be associated to the Li-ion diffusion kinetic change through the electrode when different external forces are applied. Finally, an encapsulation scheme is presented allowing sufficient bending of the device and operation for at least 500 cycles in air. The results are meant to improve the understanding of the phenomena present in thin-film batteries while undergoing bending rather than showing improvements in battery performance and lifetime.

Fabrication of amorphous Si and C anode films via co-sputtering for an all-solid-state battery

Energy Technology Data Exchange (ETDEWEB)

Lee, K.S. [Department of Materials Science and Engineering, Yonsei University Shinchondong, 262 Seongsanno, Seodaemoongu, Seoul 120-749 (Korea, Republic of); Department of Environment and Energy Engineering, Gachon University, Seongnamdaero 1342, 461-710 Gyeonggi-do (Korea, Republic of); Lee, S.H. [Department of Environment and Energy Engineering, Gachon University, Seongnamdaero 1342, 461-710 Gyeonggi-do (Korea, Republic of); Woo, S.P. [Department of Materials Science and Engineering, Yonsei University Shinchondong, 262 Seongsanno, Seodaemoongu, Seoul 120-749 (Korea, Republic of); Department of Environment and Energy Engineering, Gachon University, Seongnamdaero 1342, 461-710 Gyeonggi-do (Korea, Republic of); Kim, H.S. [Department of Mechanical Engineering, Gachon University, Seongnamdaero 1342, 461-710 Gyeonggi-do (Korea, Republic of); Yoon, Y.S., E-mail: benedicto@gachon.ac.kr [Department of Environment and Energy Engineering, Gachon University, Seongnamdaero 1342, 461-710 Gyeonggi-do (Korea, Republic of)

2014-08-01

In this study, a combination of silicon and carbon as the anode material for an all-solid-state battery has been investigated to overcome their individual deficiencies. The capacity of silicon thin films with an input power of 60 W shows dramatic failure after 38 cycles due to serious volume expansion. In contrast, C thin films at 60 W show high stability of cyclic performance and capacity retention. The amorphous silicon and carbon composite reduced the volume expansion of silicon during long term cycles and enhanced the low specific capacity of the carbon. This resistance of the volume expansion might be expected from the cushion effect caused by the carbon, which was confirmed by scanning electron microscope images after a 100 cycle test. These results indicate that amorphous silicon and carbon composite thin films have a high possibility as the stable anode material for an all-solid-state battery. - Highlights: • Amorphous Si/C nanocomposite thin films have been prepared by co-sputtering. • Carbon can act as a cushion effect to prevent volume expansion of Si. • Amorphous Si/C nanocomposite thin films show structure stability at 100 cycles. • Capacity of the amorphous Si/C nanocomposite thin films was enhanced considerably.

Praseodymium Cuprate Thin Film Cathodes for Intermediate Temperature Solid Oxide Fuel Cells: Roles of Doping, Orientation, and Crystal Structure.

Science.gov (United States)

Mukherjee, Kunal; Hayamizu, Yoshiaki; Kim, Chang Sub; Kolchina, Liudmila M; Mazo, Galina N; Istomin, Sergey Ya; Bishop, Sean R; Tuller, Harry L

2016-12-21

Highly textured thin films of undoped, Ce-doped, and Sr-doped Pr 2 CuO 4 were synthesized on single crystal YSZ substrates using pulsed laser deposition to investigate their area-specific resistance (ASR) as cathodes in solid-oxide fuel cells (SOFCs). The effects of T' and T* crystal structures, donor and acceptor doping, and a-axis and c-axis orientation on ASR were systematically studied using electrochemical impedance spectroscopy on half cells. The addition of both Ce and Sr dopants resulted in improvements in ASR in c-axis oriented films, as did the T* crystal structure with the a-axis orientation. Pr 1.6 Sr 0.4 CuO 4 is identified as a potential cathode material with nearly an order of magnitude faster oxygen reduction reaction kinetics at 600 °C compared to thin films of the commonly studied cathode material La 0.6 Sr 0.4 Co 0.8 Fe 0.2 O 3-δ . Orientation control of the cuprate films on YSZ was achieved using seed layers, and the anisotropy in the ASR was found to be less than an order of magnitude. The rare-earth doped cuprate was found to be a versatile system for study of relationships between bulk properties and the oxygen reduction reaction, critical for improving SOFC performance.

Synthesis and characterization of Cu–Al–Ni shape memory alloy multilayer thin films

Energy Technology Data Exchange (ETDEWEB)

Gómez-Cortés, J.F. [Dpt. Física Materia Condensada, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644, 48080 Bilbao (Spain); San Juan, J., E-mail: jose.sanjuan@ehu.es [Dpt. Física Materia Condensada, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644, 48080 Bilbao (Spain); López, G.A.; Nó, M.L. [Dpt. Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644, 48080 Bilbao (Spain)

2013-10-01

Among active materials, shape memory alloys are well recognized for their work output density. Because of that, these alloys have attracted much attention to be used in micro/nano electromechanical systems. In the present work, the electron beam evaporation technique has been used to growth, by a multilayer method, two shape memory alloy thin films with different Cu–Al–Ni composition. Multilayers have been further thermally treated to produce the alloys by solid solution diffusion. The produced multilayers have been characterized and the presence of the martensite phase in the obtained thin films was studied. Furthermore, the influence of two different coatings onto the Si substrates, namely Si/SiO{sub 2} and Si/Si{sub 3}N{sub 4}, was investigated. Mechanically stable, not detaching from the substrates, Cu–Al–Ni shape memory alloy thin films, about 1 micrometre thick, showing a martensitic transformation have been produced. - Highlights: ► Multilayer thin films of Cu–Al–Ni shape memory alloys produced by e-beam evaporation. ► SiN{sub X} 200 nm thick coating is good for high quality Cu–Al–Ni shape memory thin films. ► Thermal treatment renders Cu–Al–Ni multilayer in homogeneous martensite thin film.

Nano-sized copper tungstate thin films as positive electrodes for rechargeable Li batteries

International Nuclear Information System (INIS)

Li Chilin; Fu Zhengwen

2008-01-01

Nano-sized CuWO 4 thin films have been fabricated by radio-frequency (R.F.) sputtering deposition, and are used as positive electrode with both LiClO 4 liquid electrolyte and LiPON solid electrolyte in rechargeable lithium batteries. An initial discharge capacity of 192 and 210 mAh/g is obtainable for CuWO 4 film electrode with and without coated LiPON in liquid electrolyte, respectively. An all-solid-state cell with Li/LiPON/CuWO 4 layers shows a high-volume rate capacity of 145 μAh/cm 2 μm in first discharge, and overcomes the unfavorable electrochemical degradation observed in liquid electrolyte system. A two-step reactive mechanism is investigated by both transmission electron microscopy and selected area electron diffraction techniques. Apart from the extrusion and injection of Cu 2+ /Cu 0 , additional capacity can be achieved by the reversible reactivity of (WO 4 ) 2- framework. The chemical diffusion coefficients of Li intercalation/deintercalation are estimated by cyclic voltammetry. Nano-CuWO 4 thin film is expected to be a promising positive electrode material for high-performance rechargeable thin-film lithium batteries

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...

Modeling on the cathodoluminescence properties of the thin film phosphors for field emission flat panel displays

Science.gov (United States)

Cho, Kyu-Gong

2000-12-01

In order to investigate the effects of the film roughness with the fundamental luminance parameters of thin film phosphors, Y2 O3:Eu films with different thickness and roughness values were deposited on various substrate materials using a pulsed laser deposition technique under a controlled experimental procedure. The best luminous efficiency was observed from the Y2O3:Eu films on quartz substrates due to the smaller refractive index and low absorption characteristics of the quartz substrates which produce a larger amount of total internal reflection in the film and low loss of light intensity during the multiple internal reflections. The trapped light inside the film can escape the film more easily due to rougher film surface. The better epitaxial growth capability of the Y2O 3:Eu films with the LaAlO3 substrates resulted in higher luminous efficiency in the small surface roughness region. Higher luminous efficiency was observed in reflection mode than in transmission mode due to the contribution of diffusely scattered light at the air-film interface. A new theoretical model based on the diffraction scattering theory of light, the steady-state diffusion condition of carriers and the Kanaya-Okayama's electron- beam-solid interaction range satisfactorily explains all the experimental results mentioned above. The model also provides solid understandings on the cathodoluminescence properties of the thin film phosphors with the effects of other single or multiple luminance parameters. The parameters encountered for the model are surface roughness, electron-beam-solid interaction, surface recombination rate of carriers, charge carrier diffusion properties, multiple scattering at the interfaces (air- film, film-substrate, and substrate-air), optical properties of the material, film thickness, and substrate type. The model supplies a general solution in both qualitative and quantitative ways to estimate the luminance properties of the thin film phosphors and it can be

Characterization of nano-powder grown ultra-thin film p-CuO/n-Si hetero-junctions by employing vapour-liquid-solid method for photovoltaic applications

Energy Technology Data Exchange (ETDEWEB)

Sultana, Jenifar; Das, Anindita [Centre for Research in Nanoscience and Nanotechnology (CRNN), Kolkata 700098 (India); Das, Avishek [Department of Electronic Science, University of Calcutta, Kolkata 700009 (India); Saha, Nayan Ranjan [Department of Polymer Science and Technology, University of Calcutta, Kolkata 700009 (India); Karmakar, Anupam [Department of Electronic Science, University of Calcutta, Kolkata 700009 (India); Chattopadhyay, Sanatan, E-mail: scelc@caluniv.ac.in [Department of Electronic Science, University of Calcutta, Kolkata 700009 (India)

2016-08-01

In this work, the CuO nano-powder has been synthesized by employing chemical bath deposition technique for its subsequent use to grow ultrathin film (20 nm) of p-CuO on n-Si substrate for the fabrication of p-CuO/n-Si hetero-junction diodes. The thin CuO film has been grown by employing vapour-liquid-solid method. The crystalline structure and chemical phase of the film are characterized by employing field-emission scanning electron microscopy and X-ray diffraction studies. Chemical stoichiometry of the film has been confirmed by using energy dispersive X-ray spectroscopy. The potential for photovoltaic applications of such films is investigated by measuring the junction current-voltage characteristics and by extracting the relevant parameters such as open circuit photo-generated voltage, short circuit current density, fill-factor and energy conversion efficiency. - Highlights: • Synthesis of CuO nano-powder by CBD method • Growth of ultra-thin film of CuO by employing VLS method for the first time • Physical and electrical characterization of such films for photovoltaic applications • Estimation of energy conversion efficiency of the p-CuO/n-Si p-n junction solar cell.

Elaboration of a semiconductive thin film device technology on the basis of monocrystalline gallium arsenide

International Nuclear Information System (INIS)

Antoshenko, V.; Taurbaev, T.; Skirnevskaya, E.; Shorin, V.; Mihajlov, L.; Bajganatova, Sh.

1996-01-01

The aim of the project: To elaborate the economical technological process of preparing super thin monocrystalline GaAs substrates and device structures for semiconductive electronics. To realize the project it is necessary to solve following problems: o to elaborate and produce the equipment for preparing of separated films and thin film multilayer structures with p-n-junction; - to study conditions of preparing plane crystal perfect separated Ga(Al)As - films; - to optimize regimes of preparing thin film structures with p- and n-conductive - layers; - to determine the optimal methods of transferring autonomous films and structures over the second substrates; - to work out preparing methods of ohmic contacts and electrical commutation; - to optimize the process of repeated use of initial monocrystalline GaAs substrate; - to prepare the samples of discrete thin film photo- and emitting devices. As the result of project realization there will be created cheap ecological technology of heterojunction optoelectronic devices on the basis of GaAs and AlGaAs solid solutions, the laboratory samples of thin film devices will be presented

Magnetic and electronic properties of SrMnO3 thin films

Science.gov (United States)

Mandal, Arup Kumar; Panchal, Gyanendra; Choudhary, R. J.; Phase, D. M.

2018-05-01

Single phase hexagonal bulk SrMnO3 (SMO) was prepared by solid state route and it was used for depositing thin films by pulsed laser deposition (PLD) technique on single crystalline (100) oriented SrTiO3 (STO) substrate. X-ray diffraction shows that the thin film is deposited in cubic SrMnO3 phase. From X-ray absorption at the Mn L edge we observed the mixed valency of Mn (Mn3+& Mn4+) due to strain induced by the lattice mismatching between SMO and STO. Due to this mixed valency of Mn ion in SMO film, the ferromagnetic nature is observed at lower temperature because of double exchange. After post annealing with very low oxygen partial pressure, magnetic and electronic property of SMO films are effectively modified.

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.

TAPE CALENDERING MANUFACTURING PROCESS FOR MULTILAYER THIN-FILM SOLID OXIDE FUEL CELLS

Energy Technology Data Exchange (ETDEWEB)

Nguyen Minh; Kurt Montgomery

2004-10-01

This report summarizes the work performed by Hybrid Power Generation Systems, LLC during the Phases I and II under Contract DE-AC26-00NT40705 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Tape Calendering Manufacturing Process For Multilayer Thin-Film Solid Oxide Fuel Cells''. The main objective of this project was to develop the manufacturing process based on tape calendering for multilayer solid oxide fuel cells (SOFC's) using the unitized cell design concept and to demonstrate cell performance under specified operating conditions. Summarized in this report is the development and improvements to multilayer SOFC cells and the unitized cell design. Improvements to the multilayer SOFC cell were made in electrochemical performance, in both the anode and cathode, with cells demonstrating power densities of nearly 0.9 W/cm{sup 2} for 650 C operation and other cell configurations showing greater than 1.0 W/cm{sup 2} at 75% fuel utilization and 800 C. The unitized cell design was matured through design, analysis and development testing to a point that cell operation at greater than 70% fuel utilization was demonstrated at 800 C. The manufacturing process for both the multilayer cell and unitized cell design were assessed and refined, process maps were developed, forming approaches explored, and nondestructive evaluation (NDE) techniques examined.

Mn doped GaN thin films and nanoparticles

Czech Academy of Sciences Publication Activity Database

Šofer, Z.; Sedmidubský, D.; Huber, Š.; Hejtmánek, Jiří; Macková, Anna; Fiala, R.

2012-01-01

Roč. 9, 8-9 (2012), s. 809-824 ISSN 1475-7435 R&D Projects: GA ČR GA104/09/0621 Institutional research plan: CEZ:AV0Z10100521; CEZ:AV0Z10480505 Keywords : GaN nanoparticles * GaN thin films * manganese * transition metals * MOVPE * ion implantations Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.087, year: 2012

Thin Film Photovoltaic Partnership Project | Photovoltaic Research | NREL

Science.gov (United States)

Thin Film Photovoltaic Partnership Project Thin Film Photovoltaic Partnership Project NREL's Thin Film Photovoltaic (PV) Partnership Project led R&D on emerging thin-film solar technologies in the United States from 1994 to 2009. The project made many advances in thin-film PV technologies that allowed

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...

Characterization of Ag-doped vanadium oxide (AgxV2O5) thin film for cathode of thin film battery

International Nuclear Information System (INIS)

Hwang, H.S.; Oh, S.H.; Kim, H.S.; Cho, W.I.; Cho, B.W.; Lee, D.Y.

2004-01-01

The effect of silver co-sputtering on the characteristics of amorphous V 2 O 5 films, grown by dc reactive sputtering, is investigated. The co-sputtering process influences the growth mechanism as well as the characteristics of the V 2 O 5 films. X-ray diffraction (XRD), Inductively coupled plasma-atomic emission spectrometry (ICP-AES), field emission-scanning electron microscopy (FE-SEM), Fourier transform infrared spectrometry (FT-IR) and X-ray photoelectron spectrometry (XPS) results indicate that the microstructure of the V 2 O 5 films is affected by the rf power of the co-sputtered silver. In addition, an all-solid-state thin film battery with full cell structure of Li/LiPON/Ag x V 2 O 5 /Pt has been fabricated. It is found that the silver co-sputtered V 2 O 5 cathode film exhibits better cycle performance than an undoped one

Calixarene Langmuir-Blodgett Thin Films For Volatile Organic Compounds

International Nuclear Information System (INIS)

Capan, R.

2010-01-01

Volatile Organic Compounds (VOC's) such as benzene, toluene, chloroform are chemicals that evaporate easily at room temperature and create many health effects on young children, elderly and a person with heightened sensitivity to chemicals. Concentrations of many VOC's are consistently higher indoors (up to ten times higher) than outdoors because many household products (for example paints, varnishes, many cleaning, disinfecting, cosmetic, degreasing, hobby products etc.) contains VOC's. Some effects of VOC's for human beings can be followed as the eye, nose, and throat irritations; headaches, loss of coordination, nausea; damage to liver, kidneys, and central nervous system. These are big incentives for the development of portable, user-friendly VOC's sensors and for the investigation of the sensing properties of new materials to be prepared as a thin film sensing element. Langmuir-Blodgett (LB) ultra-thin film technique allows us to produce monolayer or multilayer organic thin films that can be used as chemical sensing elements.In this work, materials known as the calix[n]arene are investigated for the production of sensing material against several VOC's such as the chloroform, benzene, ethylbenzene and toluene by using LB thin film techniques. UV-visible, Quartz Crystal Microbalance (QCM) system and Surface Plasmon Resonance (SPR) measurement techniques are used to check the quality of the deposition process onto a solid substrate. Surface morphology and sensing properties of the final sensing layers are then studied by Atomic Force Microscopy (AFM) and SPR techniques. Our results indicated that selected calixarene materials are sensitive enough and quite suitable to fabricate a highly ordered, reproducible and uniform LB film that can be used as a very thin sensing layer against VOC's.

Characterization of organic thin films

CERN Document Server

Ulman, Abraham; Evans, Charles A

2009-01-01

Thin films based upon organic materials are at the heart of much of the revolution in modern technology, from advanced electronics, to optics to sensors to biomedical engineering. This volume in the Materials Characterization series introduces the major common types of analysis used in characterizing of thin films and the various appropriate characterization technologies for each. Materials such as Langmuir-Blodgett films and self-assembled monolayers are first introduced, followed by analysis of surface properties and the various characterization technologies used for such. Readers will find detailed information on: -Various spectroscopic approaches to characterization of organic thin films, including infrared spectroscopy and Raman spectroscopy -X-Ray diffraction techniques, High Resolution EELS studies, and X-Ray Photoelectron Spectroscopy -Concise Summaries of major characterization technologies for organic thin films, including Auger Electron Spectroscopy, Dynamic Secondary Ion Mass Spectrometry, and Tra...

Thermoluminescent properties of nanocrystalline ZnTe thin films: Structural and morphological studies

Science.gov (United States)

Rajpal, Shashikant; Kumar, S. R.

2018-04-01

Zinc Telluride (ZnTe) is a binary II-VI direct band gap semiconducting material with cubic structure and having potential applications in different opto-electronic devices. Here we investigated the effects of annealing on the thermoluminescence (TL) of ZnTe thin films. A nanocrystalline ZnTe thin film was successfully electrodeposited on nickel substrate and the effect of annealing on structural, morphological, and optical properties were studied. The TL emission spectrum of as deposited sample is weakly emissive in UV region at ∼328 nm. The variation in the annealing temperature results into sharp increase in emission intensity at ∼328 nm along with appearance of a new peak at ∼437 nm in visible region. Thus, the deposited nanocrystalline ZnTe thin films exhibited excellent thermoluminescent properties upon annealing. Furthermore, the influence of annealing (annealed at 400 °C) on the solid state of ZnTe were also studied by XRD, SEM, EDS, AFM. It is observed that ZnTe thin film annealed at 400 °C after deposition provide a smooth and flat texture suited for optoelectronic applications.

Characterization of Pb(Zr, Ti)O sub 3 thin films prepared by metal-organic chemical-vapor deposition using a solid delivery system

CERN Document Server

Shin, J C; Hwang, C S; Kim, H J; Lee, J M

1999-01-01

Pb(Zr, Ti)O sub 3 (PZT) thin films were deposited on Pt/SiO sub 2 /Si substrates by metal-organic chemical-vapor deposition technique using a solid delivery system to improve the reproducibility of the deposition. The self-regulation mechanism, controlling the Pb-content of the film, was observed to work above a substrate temperature of 620 .deg. C. Even with the self-regulation mechanism, PZT films having low leakage current were obtained only when the molar mixing ratio of the input precursors was 1

High resolution hard X-ray photoemission using synchrotron radiation as an essential tool for characterization of thin solid films

International Nuclear Information System (INIS)

Kim, J.J.; Ikenaga, E.; Kobata, M.; Takeuchi, A.; Awaji, M.; Makino, H.; Chen, P.P.; Yamamoto, A.; Matsuoka, T.; Miwa, D.; Nishino, Y.; Yamamoto, T.; Yao, T.; Kobayashi, K.

2006-01-01

Recently, we have shown that hard X-ray photoemission spectroscopy using undulator X-rays at SPring-8 is quite feasible with both high resolution and high throughput. Here we report an application of hard X-ray photoemission spectroscopy to the characterization of electronic and chemical states of thin solid films, for which conventional PES is not applicable. As a typical example, we focus on the problem of the scatter in the reported band-gap values for InN. We show that oxygen incorporation into the InN film strongly modifies the valence and plays a crucial role in the band gap problem. The present results demonstrate the powerful applicability of high resolution photoemission spectroscopy with hard X-rays from a synchrotron source

Impact of the substrate on the efficiency of thin film thermoelectric technology

International Nuclear Information System (INIS)

Alvarez-Quintana, J.

2015-01-01

Thermoelectricity is one of the simplest technologies for thermal energy conversion. Moreover, because of their relatively low efficiency, bulk thermoelectric materials are generally used in environments where their solid state nature outweighs their poor efficiency. Nevertheless, low dimensional thermoelectric materials shed a light in order to achieve higher thermoelectric performance than their bulk counterparts via quantum and spatial confinement of energy carriers. The Thermoelectric figure of merit ZT is the basic criterion for estimating the performance of thermoelectric materials. In this work, by way of an extension of the Harman method to thin films onto substrate to evaluate ZT it is shown that the solely presence of a substrate affects significantly the intrinsic value of the ZT independently of the electrical and thermal nature of the substrate. Furthermore, the model unveils that as the thickness ratio between substrate and thin film increases, the parameter ZT sharply tends to zero; this effect opens a serious problem to overcome by the thin film thermoelectric technology, especially at nanoscale. In this sense, challenges in order to engineering planar thermoelectric devices at micro/nanoscale are properly identified. - Highlights: • Extended Harman method to evaluate ZT of thin films onto substrate is presented. • ZT of thermoelectric thin films is strongly affected by substrate's nature. • Thin dielectric substrates are desirable to hold ZT in in-plane configuration. • Film/substrate thickness ratio play important role on the device performance. • Challenges to engineering planar thermoelectric devices are properly identified

solution growth and characterization of copper oxide thin films ...

African Journals Online (AJOL)

Thin films of copper oxide (CuO) were grown on glass slides by using the solution growth technique. Copper cloride (CuCl ) and potassium telluride (K T O ) were used. Buffer 2 2e 3 solution was used as complexing agent. The solid state properties and optical properties were obtained from characterization done using PYE ...

Influence of the substrate on the morphological evolution of gold thin films during solid-state dewetting

International Nuclear Information System (INIS)

Nsimama, Patrick D.; Herz, Andreas; Wang, Dong; Schaaf, Peter

2016-01-01

Highlights: • Dewetting of thin gold films is faster on TiO_2 than on SiO_2. • Dewetting of thin gold films is faster on amorphous TiO_2 than on crystalline TiO_2. • The kinetics is attributed to the energy of adhesion. • The morphology of thin Au films deposited on TiO_2 substrates is different to those deposited on SiO_2 substrates. • The dewetting activation energy of Au films deposited on crystalline substrates was higher than the activation energy of Au nanofilms deposited on amorphous TiO_2 substrates. - Abstract: The evolution of electron-beam evaporated Au thin films deposited on crystalline TiO_2 (c-TiO_2) and amorphous TiO_2 (a-TiO_2) as well as amorphous SiO_2 substrates are investigated. The kinetic of dewetting is clearly dependent on the type of substrate and is faster on TiO_2 substrates than on SiO_2 substrates. This difference can result from the difference in adhesion energy. Furthermore, the kinetic of dewetting is faster on a-TiO_2 than on c-TiO_2, possibly due to the crystallization of TiO_2 during annealing induced dewetting process. The morphologies of dewetted Au films deposited on crystalline TiO_2 are characterized by branched holes. The XRD patterns of the Au films deposited on TiO_2 substrates constituted peaks from both metallic Au and anatase TiO_2. The activation energy of Au films deposited on crystalline TiO_2 substrates was higher than that that of the films deposited on amorphous TiO_2 substrates.

Decomposition of poly(amide-imide) film enameled on solid copper wire using atmospheric pressure non-equilibrium plasma.

Science.gov (United States)

Sugiyama, Kazuo; Suzuki, Katsunori; Kuwasima, Shusuke; Aoki, Yosuke; Yajima, Tatsuhiko

2009-01-01

The decomposition of a poly(amide-imide) thin film coated on a solid copper wire was attempted using atmospheric pressure non-equilibrium plasma. The plasma was produced by applying microwave power to an electrically conductive material in a gas mixture of argon, oxygen, and hydrogen. The poly(amide-imide) thin film was easily decomposed by argon-oxygen mixed gas plasma and an oxidized copper surface was obtained. The reduction of the oxidized surface with argon-hydrogen mixed gas plasma rapidly yielded a metallic copper surface. A continuous plasma heat-treatment process using a combination of both the argon-oxygen plasma and argon-hydrogen plasma was found to be suitable for the decomposition of the poly(amide-imide) thin film coated on the solid copper wire.

Properties of laser-crystallized polycrystalline SiGe thin films

Energy Technology Data Exchange (ETDEWEB)

Weizman, Moshe

2008-06-06

In this thesis, structural, electrical, and optical properties of laser-crystallized polycrystalline Si{sub 1-x}Ge{sub x} thin films with 0thin films with 0.3film, which is directly coupled to a periodic compositional variation. - Amorphous SiGe samples that are exposed to a single laser pulse exhibit a ripple structure that evolves into a hillock structure when the samples are irradiated with additional laser pulses. - It is maintained that the main mechanism behind the structure formation is an instability of the propagating solid-liquid interface during solidification. - The study of defects with electron spin resonance showed that laser-crystallized poly-Si{sub 1-x}Ge{sub x} thin films with 0solid-phase crystallized SiGe films was lower and amounted to N{sub s}=7 x 10{sup 17} cm{sup -3}. - Germanium-rich laser-crystallized poly-SiGe thin films exhibited mostly a broad atypical electric dipole spin resonance (EDSR) signal that was accompanied by a nearly temperature-independent electrical conductivity in the range 20-100 K. - Most likely, the origin of the grain boundary conductance is due to dangling-bond defects and not impurities. Metallic-like conductance occurs when the dangling-bond defect density is above a critical value of about N{sub C} {approx} 10{sup 18} cm{sup -3}. - Laser crystallized poly-Si{sub 1-x}Ge{sub x} thin films with x{>=}0.5 exhibit optical absorption behavior that is characteristic for disordered SiGe, implying that the absorption occurs primarily at the grain boundaries. A sub-band-gap absorption peak was found for

Decomposition of oxidezed lead and aluminium thin films on molybdenum substrates

International Nuclear Information System (INIS)

Makarovskij, N.A.

1981-01-01

The decomposition of oxidized solid phase lead and aluminium thin films on molybdenum substrates in the process of diffusion annealing in the 5x10 -5 mm Hg vacuum at temperatures from 280 to 320 deg C and from 500 to 560 deg C, respectively, is investigated. The conclusion is made that failure of oxidized lead and aluminium thin film coatings is carried out by the mechanism of volumetric self-diffusion. Experimentally established values of activation energies of the process of lead (Qsub(Mo)sup(Pb)=29 kcal/mol) and aluminium (Qsub(Mo)sup(Al)=35 kcal/mol) film failure are close to corresponding activation energies of lead and aluminium volumetric self-diffusion, which agrees with the conclusions made [ru

A study of growth and thermal dewetting behavior of ultra-thin gold films using transmission electron microscopy

Directory of Open Access Journals (Sweden)

Sudheer

2017-07-01

Full Text Available The growth and solid-state dewetting behavior of Au thin films (0.7 to 8.4 nm deposited on the formvar film (substrate by sputtering technique have been studied using transmission electron microscopy. The size and number density of the Au nanoparticles (NPs change with an increase in the film thickness (0.7 to 2.8 nm. Nearly spherical Au NPs are obtained for 6 nm show capability to be used as an irreversible temperature sensor with a sensitivity of ∼0.1 CAF/°C. It is observed that annealing affects the crystallinity of the Au grains in the films. The electron diffraction measurement also shows annealing induced morphological evolution in the percolated Au thin films (≥3 nm during solid-state dewetting and recrystallization of the grains.

Photovoltaic behaviour of titanyl phthalocyanine thin films and titania bilayer films

Czech Academy of Sciences Publication Activity Database

Drabik, M.; Zachary, A. M.; Choi, Y.; Hanuš, J.; Toušek, J.; Toušková, J.; Cimrová, Věra; Slavinská, D.; Biederman, H.; Hanley, L.

2008-01-01

Roč. 268, č. 1 (2008), s. 57-60 ISSN 1022-1360. [Microsymposium on Advanced Polymer Materials for Photonics and Electronics /47./. Prague, 15.07.2007-19.07.2007] R&D Projects: GA MŠk(CZ) 1M06031 Grant - others:National Science Foundation(US) CHE0241425; GA MŠk(CZ) 1P05ME754 Institutional research plan: CEZ:AV0Z40500505 Keywords : conjugated polymers * photovoltaics * phthalocyanine * thin films * titania Subject RIV: BM - Solid Matter Physics ; Magnetism

Self-Limited Growth in Pentacene Thin Films.

Science.gov (United States)

Pachmajer, Stefan; Jones, Andrew O F; Truger, Magdalena; Röthel, Christian; Salzmann, Ingo; Werzer, Oliver; Resel, Roland

2017-04-05

Pentacene is one of the most studied organic semiconducting materials. While many aspects of the film formation have already been identified in very thin films, this study provides new insight into the transition from the metastable thin-film phase to bulk phase polymorphs. This study focuses on the growth behavior of pentacene within thin films as a function of film thickness ranging from 20 to 300 nm. By employing various X-ray diffraction methods, combined with supporting atomic force microscopy investigations, one crystalline orientation for the thin-film phase is observed, while three differently tilted bulk phase orientations are found. First, bulk phase crystallites grow with their 00L planes parallel to the substrate surface; second, however, crystallites tilted by 0.75° with respect to the substrate are found, which clearly dominate the former in ratio; third, a different bulk phase polymorph with crystallites tilted by 21° is found. The transition from the thin-film phase to the bulk phase is rationalized by the nucleation of the latter at crystal facets of the thin-film-phase crystallites. This leads to a self-limiting growth of the thin-film phase and explains the thickness-dependent phase behavior observed in pentacene thin films, showing that a large amount of material is present in the bulk phase much earlier during the film growth than previously thought.

Synthesis, Characterization, and Electrochemical Properties of Polyaniline Thin Films

Science.gov (United States)

Rami, Soukaina

different scenarios. These scenarios included the study in different acid based electrolytes and different gel based electrolytes. The ultra-thin self-assembled PANI films were shown to have a faster switching time, especially for the 1 layer PANI, whereas the color contrast could be observed for the film containing the dye molecule. Also, HCl based electrolyte gave the best electrochemical reversibility compared to other acids used. For the gelatin and PVA based electrolytes, having the same concentration, the results were similar. Hence, the change in the electrolyte consistencies, from liquid to semi-solid, did not change the electrochemical properties of the films. Finally, in the EIS, it was shown that these PANI thin films exhibit a pseudo-capacitance behavior, and as the film thickness grew, the capacitance increased.

Oriented Y-typehexagonal ferrite thin films prepared by chemical

Czech Academy of Sciences Publication Activity Database

Buršík, Josef; Kužel, R.; Knížek, Karel; Drbohlav, Ivo

2013-01-01

Roč. 203, JULY (2013), s. 100-105 ISSN 0022-4596 R&D Projects: GA ČR GA13-03708S Institutional support: RVO:61388980 ; RVO:68378271 Keywords : Y-type hexagonal ferrites * chemical solution deposition * thin films * epitaxial growth Subject RIV: CA - Inorganic Chemistry; BM - Solid Matter Physics ; Magnetism (FZU-D) Impact factor: 2.200, year: 2013

Deposition and characterization of NbAIN thin films by reactive magnetron sputtering

International Nuclear Information System (INIS)

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

2016-01-01

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

Influence of the substrate on the morphological evolution of gold thin films during solid-state dewetting

Energy Technology Data Exchange (ETDEWEB)

Nsimama, Patrick D. [TU Ilmenau, Institute of Materials Engineering and Institute of Micro- and Nanotechnologies MacroNano, Chair Materials for Electrical Engineering and Electronics, 98693 Ilmenau (Germany); Dar Es Salaam Institute of Technology, P.O. Box 2958, Dar Es Salaam (Tanzania, United Republic of); Herz, Andreas; Wang, Dong [TU Ilmenau, Institute of Materials Engineering and Institute of Micro- and Nanotechnologies MacroNano, Chair Materials for Electrical Engineering and Electronics, 98693 Ilmenau (Germany); Schaaf, Peter, E-mail: peter.schaaf@tu-ilmenau.de [TU Ilmenau, Institute of Materials Engineering and Institute of Micro- and Nanotechnologies MacroNano, Chair Materials for Electrical Engineering and Electronics, 98693 Ilmenau (Germany)

2016-12-01

Highlights: • Dewetting of thin gold films is faster on TiO{sub 2} than on SiO{sub 2}. • Dewetting of thin gold films is faster on amorphous TiO{sub 2} than on crystalline TiO{sub 2}. • The kinetics is attributed to the energy of adhesion. • The morphology of thin Au films deposited on TiO{sub 2} substrates is different to those deposited on SiO{sub 2} substrates. • The dewetting activation energy of Au films deposited on crystalline substrates was higher than the activation energy of Au nanofilms deposited on amorphous TiO{sub 2} substrates. - Abstract: The evolution of electron-beam evaporated Au thin films deposited on crystalline TiO{sub 2} (c-TiO{sub 2}) and amorphous TiO{sub 2} (a-TiO{sub 2}) as well as amorphous SiO{sub 2} substrates are investigated. The kinetic of dewetting is clearly dependent on the type of substrate and is faster on TiO{sub 2} substrates than on SiO{sub 2} substrates. This difference can result from the difference in adhesion energy. Furthermore, the kinetic of dewetting is faster on a-TiO{sub 2} than on c-TiO{sub 2}, possibly due to the crystallization of TiO{sub 2} during annealing induced dewetting process. The morphologies of dewetted Au films deposited on crystalline TiO{sub 2} are characterized by branched holes. The XRD patterns of the Au films deposited on TiO{sub 2} substrates constituted peaks from both metallic Au and anatase TiO{sub 2}. The activation energy of Au films deposited on crystalline TiO{sub 2} substrates was higher than that that of the films deposited on amorphous TiO{sub 2} substrates.

Cycling-induced degradation of LiCoO{sub 2} thin-film cathodes at elevated temperature

Energy Technology Data Exchange (ETDEWEB)

Van Sluytman, J.S.; Alamgir, F.M.; Greenbaum, S.G. [Department of Physics and Astronomy, Hunter College of the City University of New York, 695 Park Avenue, New York, NY 10021 (United States); West, W.C.; Whitacre, J.F. [Electrochemical Technologies Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

2006-04-01

The cycle life of LiCoO{sub 2}-based all solid-state thin-film cells has been studied at room temperature, and at elevated temperatures of 50, 100, and 150{sup o}C. X-ray diffraction, as well as Raman analysis, has been used to complement the electrochemical data in examining structural and chemical changes. XRD and Raman spectroscopy data indicate that elevated temperature soaks of the thin-film batteries in the quiescent state causes no discernible changes in the LiCoO{sub 2} cathode layer. However, when the thin-film batteries are cycled at elevated temperatures, decreases in average grain size of the LiCoO{sub 2} film occur with dramatic concomitant charge and discharge capacity loss. (author)

Thin films for precision optics

International Nuclear Information System (INIS)

Araujo, J.F.; Maurici, N.; Castro, J.C. de

1983-01-01

The technology of producing dielectric and/or metallic thin films for high precision optical components is discussed. Computer programs were developed in order to calculate and register, graphically, reflectance and transmittance spectra of multi-layer films. The technology of vacuum evaporation of several materials was implemented in our thin-films laboratory; various films for optics were then developed. The possibility of first calculate film characteristics and then produce the film is of great advantage since it reduces the time required to produce a new type of film and also reduces the cost of the project. (C.L.B.) [pt

Analysis of Hard Thin Film Coating

Science.gov (United States)

Shen, Dashen

1998-01-01

MSFC is interested in developing hard thin film coating for bearings. The wearing of the bearing is an important problem for space flight engine. Hard thin film coating can drastically improve the surface of the bearing and improve the wear-endurance of the bearing. However, many fundamental problems in surface physics, plasma deposition, etc, need further research. The approach is using electron cyclotron resonance chemical vapor deposition (ECRCVD) to deposit hard thin film an stainless steel bearing. The thin films in consideration include SiC, SiN and other materials. An ECRCVD deposition system is being assembled at MSFC.

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

Light management in large area thin-film silicon solar modules

Czech Academy of Sciences Publication Activity Database

Losio, P.A.; Caglar, O.; Cashmore, J.S.; Hötzel, J.E.; Ristau, S.; Holovský, Jakub; Remeš, Zdeněk; Sinicco, I.

2015-01-01

Roč. 143, Dec (2015), s. 375-385 ISSN 0927-0248 R&D Projects: GA ČR(CZ) GA14-05053S Institutional support: RVO:68378271 Keywords : micromorph * thin-film silicon solar cells * light management * ZnO Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.732, year: 2015

Neuromorphic transistor achieved by redox reaction of WO3 thin film

Science.gov (United States)

Tsuchiya, Takashi; Jayabalan, Manikandan; Kawamura, Kinya; Takayanagi, Makoto; Higuchi, Tohru; Jayavel, Ramasamy; Terabe, Kazuya

2018-04-01

An all-solid-state neuromorphic transistor composed of a WO3 thin film and a proton-conducting electrolyte was fabricated for application to next-generation information and communication technology including artificial neural networks. The drain current exhibited a 4-order-of-magnitude increment by redox reaction of the WO3 thin film owing to proton migration. Learning and forgetting characteristics were well tuned by the gate control of WO3 redox reactions owing to the separation of the current reading path and pulse application path in the transistor structure. This technique should lead to the development of versatile and low-power-consumption neuromorphic devices.

Thin-Film Material Science and Processing | Materials Science | NREL

Science.gov (United States)

Thin-Film Material Science and Processing Thin-Film Material Science and Processing Photo of a , a prime example of this research is thin-film photovoltaics (PV). Thin films are important because cadmium telluride thin film, showing from top to bottom: glass, transparent conducting oxide (thin layer

Active frequency tuning of the cantilever nanoresonator utilizing a phase transformation of NiTi thin film

Czech Academy of Sciences Publication Activity Database

Stachiv, Ivo; Šittner, Petr; Jeng, Y.-R.; Vokoun, David

2017-01-01

Roč. 19, č. 7 (2017), s. 5161-5169 ISSN 1392-8716 R&D Projects: GA ČR GC15-13174J Institutional support: RVO:68378271 Keywords : nanoresonator * resonant frequency * thin film * smart memory alloys * NiTi film Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 0.398, year: 2016

Vacuum-Assisted Low-Temperature Synthesis of Reduced Graphene Oxide Thin-Film Electrodes for High-Performance Transparent and Flexible All-Solid-State Supercapacitors.

Science.gov (United States)

Aytug, Tolga; Rager, Matthew S; Higgins, Wesley; Brown, Forrest G; Veith, Gabriel M; Rouleau, Christopher M; Wang, Hui; Hood, Zachary D; Mahurin, Shannon M; Mayes, Richard T; Joshi, Pooran C; Kuruganti, Teja

2018-04-04

Simple and easily integrated design of flexible and transparent electrode materials affixed to polymer-based substrates hold great promise to have a revolutionary impact on the functionality and performance of energy storage devices for many future consumer electronics. Among these applications are touch sensors, roll-up displays, photovoltaic cells, health monitors, wireless sensors, and wearable communication devices. Here, we report an environmentally friendly, simple, and versatile approach to produce optically transparent and mechanically flexible all-solid-state supercapacitor devices. These supercapacitors were constructed on tin-doped indium oxide coated polyethylene terephthalate substrates by intercalation of a polymer-based gel electrolyte between two reduced graphene oxide (rGO) thin-film electrodes. The rGO electrodes were fabricated simply by drop-casting of graphene oxide (GO) films, followed by a novel low-temperature (≤250 °C) vacuum-assisted annealing approach for the in situ reduction of GO to rGO. A trade-off between the optical transparency and electrochemical performance is determined by the concentration of the GO in the initial dispersion, whereby the highest capacitance (∼650 μF cm -2 ) occurs at a relatively lower optical transmittance (24%). Notably, the all-solid-state supercapacitors demonstrated excellent mechanical flexibility with a capacity retention rate above 90% under various bending angles and cycles. These attributes underscore the potential of the present approach to provide a path toward the realization of thin-film-based supercapacitors as flexible and transparent energy storage devices for a variety of practical applications.

Nanocrystal thin film fabrication methods and apparatus

Science.gov (United States)

Kagan, Cherie R.; Kim, David K.; Choi, Ji-Hyuk; Lai, Yuming

2018-01-09

Nanocrystal thin film devices and methods for fabricating nanocrystal thin film devices are disclosed. The nanocrystal thin films are diffused with a dopant such as Indium, Potassium, Tin, etc. to reduce surface states. The thin film devices may be exposed to air during a portion of the fabrication. This enables fabrication of nanocrystal-based devices using a wider range of techniques such as photolithography and photolithographic patterning in an air environment.

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

Energy Technology Data Exchange (ETDEWEB)

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

2006-09-13

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

Structural and electrical transport properties of La2Mo2O9 thin films prepared by pulsed laser deposition

Science.gov (United States)

Paul, T.; Ghosh, A.

2017-04-01

We have studied the structure and electrical properties of La2Mo2O9 thin films of different thicknesses prepared by the laser deposition technique at different substrate temperatures. The structural properties of the thin films have been investigated using XRD, XPS, AFM, TEM, SEM, and Raman spectroscopy. The electrical transport properties of the thin films have been investigated in wide temperature and frequency ranges. The cubic nature of the thin films has been confirmed from structural analysis. An enhancement of the oxygen ion conductivity of the films up to five orders of magnitude is obtained compared to that of the bulk La2Mo2O9, suggesting usefulness of the thin films as electrolytes in micro-solid oxide fuel cells. The enhanced dc ionic conductivity of the thin films has been interpreted using the rule of the mixture model, while a power law model has been used to investigate the frequency and temperature dependences of the conductivity. The analysis of the results predicts the three-dimensional oxygen ion conduction in the thin films.

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.

Thin film tritium dosimetry

Science.gov (United States)

Moran, Paul R.

1976-01-01

The present invention provides a method for tritium dosimetry. A dosimeter comprising a thin film of a material having relatively sensitive RITAC-RITAP dosimetry properties is exposed to radiation from tritium, and after the dosimeter has been removed from the source of the radiation, the low energy electron dose deposited in the thin film is determined by radiation-induced, thermally-activated polarization dosimetry techniques.

Low-pressure chemical vapor deposition as a tool for deposition of thin film battery materials

NARCIS (Netherlands)

Oudenhoven, J.F.M.; Dongen, van T.; Niessen, R.A.H.; Croon, de M.H.J.M.; Notten, P.H.L.

2009-01-01

Low Pressure Chemical Vapor Deposition was utilized for the deposition of LiCoO2 cathode materials for all-solid-state thin-film micro-batteries. To obtain insight in the deposition process, the most important process parameters were optimized for the deposition of crystalline electrode films on

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.

Thermal stability, microstructure and mechanical properties of Ti1-xZrxN thin films

International Nuclear Information System (INIS)

Hoerling, A.; Sjoelen, J.; Willmann, H.; Larsson, T.; Oden, M.; Hultman, L.

2008-01-01

Single-phase [NaCl]-structure Ti 1-x Zr x N thin films (0 1-x Zr x N films is proposed to be solid-solution hardening through local lattice strain fields originating from difference in atomic radius of Ti and Zr. The material system is thus promising for cutting tool applications

Interfaces and thin films physics

International Nuclear Information System (INIS)

Equer, B.

1988-01-01

The 1988 progress report of the Interfaces and Thin Film Physics laboratory (Polytechnic School France) is presented. The research program is focused on the thin films and on the interfaces of the amorphous semiconductor materials: silicon and silicon germanium, silicon-carbon and silicon-nitrogen alloys. In particular, the following topics are discussed: the basic processes and the kinetics of the reactive gas deposition, the amorphous materials manufacturing, the physico-chemical characterization of thin films and interfaces and the electron transport in amorphous semiconductors. The construction and optimization of experimental devices, as well as the activities concerning instrumentation, are also described [fr

Buckling of Thin Films in Nano-Scale

Directory of Open Access Journals (Sweden)

Li L.A.

2010-06-01

Full Text Available Investigation of thin film buckling is important for life prediction of MEMS device which are damaged mainly by the delamination and buckling of thin films. In this paper the mechanical and thermal properties of compressed thin film titanium films with 150 nm thickness deposited on an organic glass substrate under mechanical and thermal loads were measured and characterized. In order to simulate the thin films which subjected to compound loads and the buckle modes the external uniaxial compression and thermal loading were subjected to the specimen by the symmetric loading device and the electrical film in this experiment. The temperature of the thin film deposited on substrate was measured using thermoelectric couple. The range of temperature accords with the temperature range of the MEMS. It is found that the size and number of the delamination and buckling of the film are depended upon the pre-fixed mechanical loading and thermal temperature. The thermal transient conduction and thermal stability of the film and substrate was studied with finite element method.

Spin Seebeck effect in Y-type hexagonal ferrite thin films

Czech Academy of Sciences Publication Activity Database

Hirschner, Jan; Maryško, Miroslav; Hejtmánek, Jiří; Uhrecký, Róbert; Soroka, Miroslav; Buršík, Josef; Anadón, P.; Aguirre, M.H.; Knížek, Karel

2017-01-01

Roč. 96, č. 6 (2017), s. 1-8, č. článku 064428. ISSN 2469-9950 R&D Projects: GA ČR(CZ) GA14-18392S Institutional support: RVO:68378271 ; RVO:61388980 Keywords : hexagonal ferrites * spin Seebeck effect * thin films * magnetization * ferrimagnetic ferrites Subject RIV: BM - Solid Matter Physics ; Magnetism; CA - Inorganic Chemistry (UACH-T) OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.); Inorganic and nuclear chemistry (UACH-T) Impact factor: 3.836, year: 2016

Investigation of nanoporous platinum thin films fabricated by reactive sputtering: Application as micro-SOFC electrode

Science.gov (United States)

Jung, WooChul; Kim, Jae Jin; Tuller, Harry L.

2015-02-01

Highly porous Pt thin films, with nano-scale porosity, were fabricated by reactive sputtering. The strategy involved deposition of thin film PtOx at room temperature, followed by the subsequent decomposition of the oxide by rapid heat treatment. The resulting films exhibited percolating Pt networks infiltrated with interconnected nanosized pores, critical for superior solid oxide fuel cell cathode performance. This approach is particularly attractive for micro-fabricated solid oxide fuel cells, since it enables fabrication of the entire cell stack (anode/electrolyte/cathode) within the sputtering chamber, without breaking vacuum. In this work, the morphological, crystallographic and chemical properties of the porous electrode were systematically varied by control of deposition conditions. Oxygen reduction reaction kinetics were investigated by means of electrochemical impedance spectroscopy, demonstrating the critical role of nano-pores in achieving satisfactory micro-SOFC cathode performance.

Surface Structure and Photocatalytic Activity of Nano-TiO2 Thin Film

Science.gov (United States)

Controlled titanium dioxide (TiO2) thin films were deposited on stainless steel surfaces using flame aerosol synthetic technique, which is a one-step coating process, that doesn’t require further calcination. Solid state characterization of the coatings was conducted by different...

Thin films

International Nuclear Information System (INIS)

Strongin, M.; Miller, D.L.

1976-01-01

This article reviews the phenomena that occur in films from the point of view of a solid state physicist. Films form the basis for many established and developing technologies. Metal layers have always been important for optical coatings and as protective coatings. In the most sophisticated cases, films and their interaction on silicon surfaces form the basis of modern electronic technology. Films of silicon, GaAs and composites of these materials promise to lead to practical photovoltaic devices

Operating method of amorphous thin film semiconductor element

Energy Technology Data Exchange (ETDEWEB)

Mori, Koshiro; Ono, Masaharu; Hanabusa, Akira; Osawa, Michio; Arita, Takashi

1988-05-31

The existing technologies concerning amorphous thin film semiconductor elements are the technologies concerning the formation of either a thin film transistor or an amorphous Si solar cell on a substrate. In order to drive a thin film transistor for electronic equipment control by the output power of an amorphous Si solar cell, it has been obliged to drive the transistor weth an amorphous solar cell which was formed on a substrate different from that for the transistor. Accordingly, the space for the amorphous solar cell, which was formed on the different substrate, was additionally needed on the substrate for the thin film transistor. In order to solve the above problem, this invention proposes an operating method of an amorphous thin film semiconductor element that after forming an amorphous Si solar cell through lamination on the insulation coating film which covers the thin film transistor formed on the substrate, the thin film transistor is driven by the output power of this solar cell. The invention eliminates the above superfluous space and reduces the size of the amorphous thin film semiconductor element including the electric source. (3 figs)

Temperature dependence of LRE-HRE-TM thin films

Science.gov (United States)

Li, Zuoyi; Cheng, Xiaomin; Lin, Gengqi; Li, Zhen; Huang, Zhixin; Jin, Fang; Wang, Xianran; Yang, Xiaofei

2003-04-01

Temperature dependence of the properties of RE-TM thin films is very important for MO recording. In this paper, we studied the temperature dependence of the magnetic and magneto-optical properties of the amorphous LRE-HRE-TM single layer thin films and LRE-HRE-TM/HRE-TM couple-bilayered thin films. For LRE-HRE-TM single layer thin films, the temperature dependence of the magnetization was investigated by using the mean field theory. The experimental and theoretical results matched very well. With the LRE substitution in HRE-TM thin film, the compensation temperature Tcomp decreased and the curie temperature Tc remained unchanged. Kerr rotation angle became larger and the saturation magnetization Ms at room temperature increased. For LRE-HRE-TM/HRE-TM couple-bilayered thin films, comparisons of the temperature dependences of the coercivities and Kerr rotation angles were made between isolated sublayers and couple-bilayered thin film.

Study of thin insulating films using secondary ion emission

International Nuclear Information System (INIS)

Hilleret, Noel

1973-01-01

Secondary ion emission from insulating films was investigated using a CASTAING-SLODZIAN ion analyzer. Various different aspects of the problem were studied: charge flow across a silica film; the mobilization of sodium during ion bombardment; consequences of the introduction of oxygen on the emission of secondary ions from some solids; determination of the various characteristics of secondary ion emission from silica, silicon nitride and silicon. An example of measurements made using this type of operation is presented: profiles (concentration as a function of depth) of boron introduced by diffusion or implantation in thin films of silica on silicon or silicon nitride. Such measurements have applications in microelectronics. The same method of operation was extended to other types of insulating film, and in particular, to the metallurgical study of passivation films formed on the surface of stainless steels. (author) [fr

Deposition of zinc oxide thin films by reactive pulsed laser ablation

Czech Academy of Sciences Publication Activity Database

Bílková, Petra; Zemek, Josef; Mitu, B.; Marotta, V.; Orlando, S.

2006-01-01

Roč. 252, - (2006), s. 4604-4609 ISSN 0169-4332 Grant - others:NATO-CNR Outreach Fellowships Programm 2001(XE) 219.34 Institutional research plan: CEZ:AV0Z10100521 Keywords : reactive pulsed laser deposition * zinc oxide * thin films Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.436, year: 2006

Application-related properties of giant magnetostrictive thin films

International Nuclear Information System (INIS)

Lim, S.H.; Kim, H.J.; Na, S.M.; Suh, S.J.

2002-01-01

In an effort to facilitate the utilization of giant magnetostrictive thin films in microdevices, application-related properties of these thin films, which include induced anisotropy, residual stress and corrosion properties, are investigated. A large induced anisotropy with an energy of 6x10 4 J/m 3 is formed in field-sputtered amorphous Sm-Fe-B thin films, resulting in a large magnetostriction anisotropy. Two components of residual stress, intrinsic compressive stress and tensile stress due to the difference of the thermal expansion coefficients between the substrate and thin film, are identified. The variation of residual stress with fabrication parameter and annealing temperature, and its influence on mechanical bending and magnetic properties are examined. Better corrosion properties are observed in Sm-Fe thin films than in Tb-Fe. Corrosion properties of Tb-Fe thin films, however, are much improved with the introduction of nitrogen to the thin films without deteriorating magnetostrictive properties

PLD of X7R for thin film capacitors

International Nuclear Information System (INIS)

Hino, Takanori; Matsumoto, Noriyuki; Nishida, Minoru; Araki, Takao

2008-01-01

Thin film capacitors with a thickness of 200 nm were prepared on SrTiO 3 (1 0 0), (1 1 0) and (1 1 1) single crystal substrates at a temperature of 973 K by pulsed laser deposition (PLD) using a KrF excimer laser in an O 2 -O 3 atmosphere with a gas pressure of 1 Pa using an X7R sintered target. As a result, perovskite BaTiO 3 solid solution films were obtained. In the X7R thin films on (1 0 0) and (1 1 0) SrTiO 3 , only diffraction peaks with strong intensities from BaTiO 3 (1 0 0) and (1 1 0), respectively, were observed. X7R films on SrTiO 3 (1 1 1) were grown epitaxially oriented to the crystal plane direction of the substrate by inserting an initial homoepitaxial SrTiO 3 layer with a thickness of 4 nm. The X7R/SrTiO 3 film capacitors yielded a large volumetric efficiency of 50 μF/mm 3 and a temperature coefficient of capacitance (TCC) of -1.3% to 1.3% which satisfies the EIA standard specifications for X7R

Pulsed-laser-deposited YBCO thin films using modified MTG processed targets

CERN Document Server

Kim, C H; Kim, I T; Hahn, T S

1999-01-01

YBCO thin films were deposited by pulsed laser deposition from targets fabricated using the modified melt-textured growth (MTG) method and the solid-state sintering (SSS) method. All of the films showed c-axis orientations, but the films from the MTG targets had better crystallinity than those from the SSS targets. As the substrate temperature was increased, T sub c and J sub c of the films increased. The films from the MTG targets showed better superconducting properties than those from the SSS targets. From the composition analysis of the targets, the Y-richer vapor species arriving at the substrate from the MTG targets are thought to form a thermodynamically more stable YBCO phase with less cation disorder.

Analysis of thin-film polymers using attenuated total internal reflection-Raman microspectroscopy.

Science.gov (United States)

Tran, Willie; Tisinger, Louis G; Lavalle, Luis E; Sommer, André J

2015-01-01

Two methods commonly employed for molecular surface analysis and thin-film analysis of microscopic areas are attenuated total reflection infrared (ATR-IR) microspectroscopy and confocal Raman microspectroscopy. In the former method, the depth of the evanescent probe beam can be controlled by the wavelength of light, the angle of incidence, or the refractive index of the internal reflection element. Because the penetration depth is proportional to the wavelength of light, one could interrogate a smaller film thickness by moving from the mid-infrared region to the visible region employing Raman spectroscopy. The investigation of ATR Raman microspectroscopy, a largely unexplored technique available to Raman microspectroscopy, was carried out. A Renishaw inVia Raman microscope was externally modified and used in conjunction with a solid immersion lens (SIL) to perform ATR Raman experiments. Thin-film polymer samples were analyzed to explore the theoretical sampling depth for experiments conducted without the SIL, with the SIL, and with the SIL using evanescent excitation. The feasibility of micro-ATR Raman was examined by collecting ATR spectra from films whose thickness measured from 200 to 60 nm. Films of these thicknesses were present on a much thicker substrate, and features from the underlying substrate did not become visible until the thin film reached a thickness of 68 nm.

Nonepitaxial Thin-Film InP for Scalable and Efficient Photocathodes.

Science.gov (United States)

Hettick, Mark; Zheng, Maxwell; Lin, Yongjing; Sutter-Fella, Carolin M; Ager, Joel W; Javey, Ali

2015-06-18

To date, some of the highest performance photocathodes of a photoelectrochemical (PEC) cell have been shown with single-crystalline p-type InP wafers, exhibiting half-cell solar-to-hydrogen conversion efficiencies of over 14%. However, the high cost of single-crystalline InP wafers may present a challenge for future large-scale industrial deployment. Analogous to solar cells, a thin-film approach could address the cost challenges by utilizing the benefits of the InP material while decreasing the use of expensive materials and processes. Here, we demonstrate this approach, using the newly developed thin-film vapor-liquid-solid (TF-VLS) nonepitaxial growth method combined with an atomic-layer deposition protection process to create thin-film InP photocathodes with large grain size and high performance, in the first reported solar device configuration generated by materials grown with this technique. Current-voltage measurements show a photocurrent (29.4 mA/cm(2)) and onset potential (630 mV) approaching single-crystalline wafers and an overall power conversion efficiency of 11.6%, making TF-VLS InP a promising photocathode for scalable and efficient solar hydrogen generation.

Interaction of acetonitrile with thin films of solid water

International Nuclear Information System (INIS)

Bahr, S.; Kempter, V.

2009-01-01

Thin films of water were prepared on Ag at 124 K. Their properties were studied with metastable impact electron spectroscopy, reflection absorption infrared spectroscopy, and temperature programmed desorption. The interaction of acetonitrile (ACN) with these films was studied with the abovementioned techniques. From the absence of any infrared activity in the initial adsorption stage, it is concluded that ACN adsorbs linearly and that the C≡N axis is aligned parallel to the water surface (as also found on neat Ag). Initially, the interaction with water surface species involves their dangling OD groups. During the completion of the first adlayer the ACN-ACN lateral interaction becomes of importance as well, and the ACN molecules become tilted with respect to the water surface. ACN shows propensity to stay at the surface after surface adsorption even during annealing up to the onset of desorption. The present results for the ACN-water interaction are compared with available classical molecular dynamics calculations providing the orientation profile for ACN on water as well as the ACN bonding properties.

Preparation of LiMn2O4 cathode thin films for thin film lithium secondary batteries by a mist CVD process

International Nuclear Information System (INIS)

Tadanaga, Kiyoharu; Yamaguchi, Akihiro; Sakuda, Atsushi; Hayashi, Akitoshi; Tatsumisago, Masahiro; Duran, Alicia; Aparacio, Mario

2014-01-01

Highlights: • LiMn 2 O 4 thin films were prepared by using the mist CVD process. • An aqueous solution of lithium and manganese acetates is used for the precursor solution. • The cell with the LiMn 2 O 4 thin films exhibited a capacity of about 80 mAh/g. • The cell showed good cycling performance during 10 cycles. - Abstract: LiMn 2 O 4 cathode thin films for thin film lithium secondary batteries were prepared by using so-called the “mist CVD process”, employing an aqueous solution of lithium acetate and manganese acetate, as the source of Li and Mn, respectively. The aqueous solution of starting materials was ultrasonically atomized to form mist particles, and mists were transferred by nitrogen gas to silica glass substrate to form thin films. FE-SEM observation revealed that thin films obtained by this process were dense and smooth, and thin films with a thickness of about 750 nm were obtained. The electrochemical cell with the thin films obtained by sintering at 700 °C exhibited a capacity of about 80 mAh/g, and the cell showed good cycling performance during 10 cycles

P-type CuxS thin films: Integration in a thin film transistor structure

International Nuclear Information System (INIS)

Nunes de Carvalho, C.; Parreira, P.; Lavareda, G.; Brogueira, P.; Amaral, A.

2013-01-01

Cu x S thin films, 80 nm thick, are deposited by vacuum thermal evaporation of sulfur-rich powder mixture, Cu 2 S:S (50:50 wt.%) with no intentional heating of the substrate. The process of deposition occurs at very low deposition rates (0.1–0.3 nm/s) to avoid the formation of Cu or S-rich films. The evolution of Cu x S films surface properties (morphology/roughness) under post deposition mild annealing in air at 270 °C and their integration in a thin film transistor (TFT) are the main objectives of this study. Accordingly, Scanning Electron Microscopy studies show Cu x S films with different surface morphologies, depending on the post deposition annealing conditions. For the shortest annealing time, the Cu x S films look to be constructed of grains with large dimension at the surface (approximately 100 nm) and consequently, irregular shape. For the longest annealing time, films with a fine-grained surface are found, with some randomly distributed large particles bound to this fine-grained surface. Atomic Force Microscopy results indicate an increase of the root-mean-square roughness of Cu x S surface with annealing time, from 13.6 up to 37.4 nm, for 255 and 345 s, respectively. The preliminary integration of Cu x S films in a TFT bottom-gate type structure allowed the study of the feasibility and compatibility of this material with the remaining stages of a TFT fabrication as well as the determination of the p-type characteristic of the Cu x S material. - Highlights: • Surface properties of annealed Cu x S films. • Variation of conductivity with annealing temperatures of Cu x S films. • Application of evaporated Cu x S films in a thin film transistor (TFT) structure. • Determination of Cu x S p-type characteristic from TFT behaviour

Semiconductor-nanocrystal/conjugated polymer thin films

Science.gov (United States)

Alivisatos, A. Paul; Dittmer, Janke J.; Huynh, Wendy U.; Milliron, Delia

2014-06-17

The invention described herein provides for thin films and methods of making comprising inorganic semiconductor-nanocrystals dispersed in semiconducting-polymers in high loading amounts. The invention also describes photovoltaic devices incorporating the thin films.

Self-assembly of dodecaphenyl POSS thin films

Science.gov (United States)

Handke, Bartosz; Klita, Łukasz; Niemiec, Wiktor

2017-12-01

The self-assembly abilities of Dodecaphenyl Polyhedral Oligomeric Silsesquioxane thin films on Si(1 0 0) surfaces were studied. Due to their thermal properties - relatively low sublimation temperature and preservation of molecular structure - cage type silsesquioxanes are ideal material for the preparation of a thin films by Physical Vapor Deposition. The Ultra-High Vacuum environment and the deposition precision of the PVD method enable the study of early stages of thin film growth and its molecular organization. X-ray Reflectivity and Atomic Force Microscopy measurements allow to pursuit size-effects in the structure of thin films with thickness ranges from less than a single molecular layer up to several tens of layers. Thermal treatment of the thin films triggered phase change: from a poorly ordered polycrystalline film into a well-ordered multilayer structure. Self-assembly of the layers is the effect of the π-stacking of phenyl rings, which force molecules to arrange in a superlattice, forming stacks of alternating organic-inorganic layers.

TiO 2 Thin Films Prepared via Adsorptive Self-Assembly for Self-Cleaning Applications

KAUST Repository

Xi, Baojuan

2012-02-22

Low-cost controllable solution-based processes for preparation of titanium oxide (TiO 2) thin films are highly desirable, because of many important applications of this oxide in catalytic decomposition of volatile organic compounds, advanced oxidation processes for wastewater and bactericidal treatments, self-cleaning window glass for green intelligent buildings, dye-sensitized solar cells, solid-state semiconductor metal-oxide solar cells, self-cleaning glass for photovoltaic devices, and general heterogeneous photocatalysis for fine chemicals etc. In this work, we develop a solution-based adsorptive self-assembly approach to fabricate anatase TiO 2 thin films on different glass substrates such as simple plane glass and patterned glass at variable compositions (normal soda lime glass or solar-grade borofloat glass). By tuning the number of process cycles (i.e., adsorption-then-heating) of TiO 2 colloidal suspension, we could facilely prepare large-area TiO 2 films at a desired thickness and with uniform crystallite morphology. Moreover, our as-prepared nanostructured TiO 2 thin films on glass substrates do not cause deterioration in optical transmission of glass; instead, they improve optical performance of commercial solar cells over a wide range of incident angles of light. Our as-prepared anatase TiO 2 thin films also display superhydrophilicity and excellent photocatalytic activity for self-cleaning application. For example, our investigation of photocatalytic degradation of methyl orange indicates that these thin films are indeed highly effective, in comparison to other commercial TiO 2 thin films under identical testing conditions. © 2012 American Chemical Society.

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

Synthesis of high-oxidation Y-Ba-Cu-O phases in superoxygenated thin films

Science.gov (United States)

Zhang, H.; Gauquelin, N.; McMahon, C.; Hawthorn, D. G.; Botton, G. A.; Wei, J. Y. T.

2018-03-01

It is known that solid-state reaction in high-pressure oxygen can stabilize high-oxidation phases of Y-Ba-Cu-O superconductors in powder form. We extend this superoxygenation concept of synthesis to thin films which, due to their large surface-to-volume ratio, are more reactive thermodynamically. Epitaxial thin films of YBa2Cu3O7 -δ grown by pulsed laser deposition are annealed at up to 700 atm O2 and 900 ∘C , in conjunction with Cu enrichment by solid-state diffusion. The films show the clear formation of Y2Ba4Cu7O15 -δ and Y2Ba4Cu8O16 as well as regions of YBa2Cu5O9 -δ and YBa2Cu6O10 -δ phases, according to scanning transmission electron microscopy, x-ray diffraction, and x-ray absorption spectroscopy. Similarly annealed YBa2Cu3O7 -δ powders show no phase conversion. Our results demonstrate a route of synthesis towards discovering more complex phases of cuprates and other superconducting oxides.

Intercalation crystallization of phase-pure α-HC(NH₂)₂PbI₃ upon microstructurally engineered PbI₂ thin films for planar perovskite solar cells.

Science.gov (United States)

Zhou, Yuanyuan; Yang, Mengjin; Kwun, Joonsuh; Game, Onkar S; Zhao, Yixin; Pang, Shuping; Padture, Nitin P; Zhu, Kai

2016-03-28

The microstructure of the solid-PbI2 precursor thin film plays an important role in the intercalation crystallization of the formamidinium lead triiodide perovskite (α-HC(NH2)2PbI3). It is shown that microstructurally engineered PbI2 thin films with porosity and low crystallinity are the most favorable for conversion into uniform-coverage, phase-pure α-HC(NH2)2PbI3 perovskite thin films. Planar perovskite solar cells fabricated using these thin films deliver power conversion efficiency (PCE) up to 13.8%.

Solid state dewetting and stress relaxation in a thin single crystalline Ni film on sapphire

International Nuclear Information System (INIS)

Rabkin, E.; Amram, D.; Alster, E.

2014-01-01

In this study, we deposited a 80 nm thick single crystalline Ni film on a sapphire substrate. Heat treatment of this film at 1000 °C followed by slow cooling resulted in the formation of faceted holes, star-like channel instabilities and faceted microwires. The ridges at the rims of faceted holes and channels exhibited a twinning orientation relationship with the rest of the film. A sub-nanometer-high hexagonal topography pattern on the surface of the unperturbed film was observed by atomic force microscopy. No such pattern was observed on the top facets of isolated Ni particles and hole ridges. We discuss the observed dewetting patterns in terms of the effects of Ni surface anisotropy and faceting on solid state dewetting. The hexagonal pattern on the surface of the unperturbed film was attributed to thermal stress relaxation in the film via dislocations glide. This work demonstrates that solid state dewetting of single crystalline metal films can be utilized for film patterning and for producing hierarchical surface topographies

Preparation of Ferroelectric Thin Films of Bismuth Layer Structured Compounds

Science.gov (United States)

Watanabe, Hitoshi; Mihara, Takashi; Yoshimori, Hiroyuki; Araujo, Carlos

1995-09-01

Ferroelectric thin films of bismuth layer structured compounds, SrBi2Ta2O9, SrBi2Nb2O9, SrBi4Ti4O15 and their solid solutions, were formed onto a sputtered platinum layer on a silicon substrate using spin-on technique and metal-organic decomposition (MOD) method. X-ray diffraction (XRD) analysis and some electrical measurements were performed on the prepared thin films. XRD results of SrBi2(Ta1- x, Nb x)2O9 films (0≤x≤1) showed that niobium ions substitute for tantalum ions in an arbitrary ratio without any change of the layer structure and lattice constants. Furthermore, XRD results of SrBi2 xTa2O9 films (0≤x≤1.5) indicated that the formation of the bismuth layer structure does not always require an accurate bismuth content. The layer structure was formed above 50% of the stoichiometric bismuth content in the general formula. SrBi2(Ta1- x, Nb x)2O9 films with various Ta/Nb ratios have large enough remanent polarization for nonvolatile memory application and have shown high fatigue resistance against 1011 cycles of full switching of the remanent polarization. Mixture films of the three compounds were also investigated.

Novel chemical analysis for thin films

International Nuclear Information System (INIS)

Usui, Toshio; Kamei, Masayuki; Aoki, Yuji; Morishita, Tadataka; Tanaka, Shoji

1991-01-01

Scanning electron microscopy and total-reflection-angle X-ray spectroscopy (SEM-TRAXS) was applied for fluorescence X-ray analysis of 50A- and 125A-thick Au thin films on Si(100). The intensity of the AuM line (2.15 keV) emitted from the Au thin films varied as a function of the take-off angle (θ t ) with respect to the film surface; the intensity of AuM line from the 125A-thick Au thin film was 1.5 times as large as that of SiK α line (1.74 keV) emitted from the Si substrate when θ t = 0deg-3deg, in the vicinity of a critical angle for total external reflection of the AuM line at Si (0.81deg). In addition, the intensity of the AuM line emitted from the 50A-thick Au thin film was also sufficiently strong for chemical analysis. (author)

Magnetism and deformation of epitaxial Pd and Rh thin films

Czech Academy of Sciences Publication Activity Database

Káňa, Tomáš; Hüger, E.; Legut, D.; Čák, M.; Šob, Mojmír

2016-01-01

Roč. 93, č. 13 (2016), č. článku Art. number 134422. ISSN 2469-9950 R&D Projects: GA MŠk(CZ) LQ1601; GA ČR(CZ) GA16-24711S Institutional support: RVO:68081723 Keywords : ab initio calculations * magnetism * palladium * rhodium * thin films * deformation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.836, year: 2016

Thin films by metal-organic precursor plasma spray

International Nuclear Information System (INIS)

Schulz, Douglas L.; Sailer, Robert A.; Payne, Scott; Leach, James; Molz, Ronald J.

2009-01-01

While most plasma spray routes to coatings utilize solids as the precursor feedstock, metal-organic precursor plasma spray (MOPPS) is an area that the authors have investigated recently as a novel route to thin film materials. Very thin films are possible via MOPPS and the technology offers the possibility of forming graded structures by metering the liquid feed. The current work employs metal-organic compounds that are liquids at standard temperature-pressure conditions. In addition, these complexes contain chemical functionality that allows straightforward thermolytic transformation to targeted phases of interest. Toward that end, aluminum 3,5-heptanedionate (Al(hd) 3 ), triethylsilane (HSi(C 2 H 5 ) 3 or HSiEt 3 ), and titanium tetrakisdiethylamide (Ti(N(C 2 H 5 ) 2 ) 4 or Ti(NEt 2 ) 4 ) were employed as precursors to aluminum oxide, silicon carbide, and titanium nitride, respectively. In all instances, the liquids contain metal-heteroatom bonds envisioned to provide atomic concentrations of the appropriate reagents at the film growth surface, thus promoting phase formation (e.g., Si-C bond in triethylsilane, Ti-N bond in titanium amide, etc.). Films were deposited using a Sulzer Metco TriplexPro-200 plasma spray system under various experimental conditions using design of experiment principles. Film compositions were analyzed by glazing incidence x-ray diffraction and elemental determination by x-ray spectroscopy. MOPPS films from HSiEt 3 showed the formation of SiC phase but Al(hd) 3 -derived films were amorphous. The Ti(NEt 2 ) 4 precursor gave MOPPS films that appear to consist of nanosized splats of TiOCN with spheres of TiO 2 anatase. While all films in this study suffered from poor adhesion, it is anticipated that the use of heated substrates will aid in the formation of dense, adherent films.

Nanostructured thin film coatings with different strengthening effects

Directory of Open Access Journals (Sweden)

Panfilov Yury

2017-01-01

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

Development of Flexible, Free-Standing, Thin Films for Additive Manufacturing and Localized Energy Generation

Science.gov (United States)

2015-08-10

does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. Texas Technical University Box 41035 349...upon reaction. All films were cast at a thickness of 1 mm with constant volume percent solids to ensure consistent rheological properties. The films...2005); 10.1063/1.2058175 Local dynamic mechanical properties in model free-standing polymer thin films J. Chem. Phys. 122, 144712 (2005); 10.1063

Thin Film Photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Zweibel, K.

1998-11-19

The motivation to develop thin film technologies dates back to the inception of photovoltaics. It is an idea based on achieving truly low-cost photovoltaics appropriate for mass production and energy significant markets. The key to the idea is the use of pennies worth of active materials. Since sunlight carries relatively little energy in comparison with combustion-based energy sources, photovoltaic (PV) modules must be cheap to produce energy that can be competitive. Thin films are presumed to be the answer to that low-cost requirement. But how cheap do they have to be? The following is an oversimplified analysis that allows some insight into this question.

Thin films: Past, present, future

Energy Technology Data Exchange (ETDEWEB)

Zweibel, K

1995-04-01

This report describes the characteristics of the thin film photovoltaic modules necessary for an acceptable rate of return for rural areas and underdeveloped countries. The topics of the paper include a development of goals of cost and performance for an acceptable PV system, a review of current technologies for meeting these goals, issues and opportunities in thin film technologies.

Non-linear optics of nano-scale pentacene thin film

Science.gov (United States)

Yahia, I. S.; Alfaify, S.; Jilani, Asim; Abdel-wahab, M. Sh.; Al-Ghamdi, Attieh A.; Abutalib, M. M.; Al-Bassam, A.; El-Naggar, A. M.

2016-07-01

We have found the new ways to investigate the linear/non-linear optical properties of nanostructure pentacene thin film deposited by thermal evaporation technique. Pentacene is the key material in organic semiconductor technology. The existence of nano-structured thin film was confirmed by atomic force microscopy and X-ray diffraction. The wavelength-dependent transmittance and reflectance were calculated to observe the optical behavior of the pentacene thin film. It has been observed the anomalous dispersion at wavelength λ 800. The non-linear refractive index of the deposited films was investigated. The linear optical susceptibility of pentacene thin film was calculated, and we observed the non-linear optical susceptibility of pentacene thin film at about 6 × 10-13 esu. The advantage of this work is to use of spectroscopic method to calculate the liner and non-liner optical response of pentacene thin films rather than expensive Z-scan. The calculated optical behavior of the pentacene thin films could be used in the organic thin films base advanced optoelectronic devices such as telecommunications devices.

Hard X-ray photoemission spectroscopy of transition-metal oxide thin films and interfaces

International Nuclear Information System (INIS)

Wadati, H.; Fujimori, A.

2013-01-01

Highlights: •Photoemission spectroscopy is a powerful technique to study the electronic structures of transition-metal oxides. •Hard X-ray photoemission spectroscopy (HXPES) is a new type of photoemission spectroscopy which can probe bulk states. •HXPES is very suitable for studying oxide thin films such as the composition dependence and the film thickness dependence. -- Abstract: Photoemission spectroscopy is a powerful experimental technique to study the electronic structures of solids, especially of transition-metal oxides. Recently, hard X-ray photoemission spectroscopy (HXPES) has emerged as a more relevant experimental technique to obtain clear information about bulk states. Here, we describe how HXPES can be conveniently applied to study the interesting subjects on oxide thin films such as the composition dependence and the film thickness dependence of the electronic structures and the interfacial electronic structure of multilayers

Oxidation of ruthenium thin films using atomic oxygen

Energy Technology Data Exchange (ETDEWEB)

McCoy, A.P.; Bogan, J.; Brady, A.; Hughes, G.

2015-12-31

In this study, the use of atomic oxygen to oxidise ruthenium thin films is assessed. Atomic layer deposited (ALD) ruthenium thin films (~ 3 nm) were exposed to varying amounts of atomic oxygen and the results were compared to the impact of exposures to molecular oxygen. X-ray photoelectron spectroscopy studies reveal substantial oxidation of metallic ruthenium films to RuO{sub 2} at exposures as low as ~ 10{sup 2} L at 575 K when atomic oxygen was used. Higher exposures of molecular oxygen resulted in no metal oxidation highlighting the benefits of using atomic oxygen to form RuO{sub 2}. Additionally, the partial oxidation of these ruthenium films occurred at temperatures as low as 293 K (room temperature) in an atomic oxygen environment. - Highlights: • X-ray photoelectron spectroscopy study of the oxidation of Ru thin films • Oxidation of Ru thin films using atomic oxygen • Comparison between atomic oxygen and molecular oxygen treatments on Ru thin films • Fully oxidised RuO{sub 2} thin films formed with low exposures to atomic oxygen.

Enhancement of YBCO thin film thermal stability under 1 ATM oxygen pressure by Intermediate Cu.sub.2./sub. O nanolayer

Czech Academy of Sciences Publication Activity Database

Cheng, L.; Wang, X.; Yao, X.; Wan, W.; Li, F.H.; Xiong, J.; Tao, B.W.; Jirsa, Miloš

2010-01-01

Roč. 114, č. 22 (2010), s. 7543-7547 ISSN 1520-6106 R&D Projects: GA MŠk(CZ) ME10069 Institutional research plan: CEZ:AV0Z10100520 Keywords : YBCO thin films * thermal stability * thin film growth orientation * temperature optical microscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.603, year: 2010

Thin Films in the Photovoltaic Industry

International Nuclear Information System (INIS)

Jaeger-Waldau, A.

2008-03-01

In the past years, the yearly world market growth rate for Photovoltaics was an average of more than 40%, which makes it one of the fastest growing industries at present. Business analysts predict the market volume to increase to 40 billion euros in 2010 and expect rising profit margins and lower prices for consumers at the same time. Today PV is still dominated by wafer based Crystalline Silicon Technology as the 'working horse' in the global market, but thin films are gaining market shares. For 2007 around 12% are expected. The current silicon shortage and high demand has kept prices higher than anticipated from the learning curve experience and has widened the windows of opportunities for thin film solar modules. Current production capacity estimates for thin films vary between 3 and 6 GW in 2010, representing a 20% market share for these technologies. Despite the higher growth rates for thin film technologies compared with the industry average, Thin Film Photovoltaic Technologies are still facing a number of challenges to maintain this growth and increase market shares. The four main topics which were discussed during the workshop were: Potential for cost reduction; Standardization; Recycling; Performance over the lifetime.

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

Measuring and modelling of diffusivities in carbohydrate-rich matrices during thin film drying

NARCIS (Netherlands)

Perdana, J.A.; Sman, van der R.G.M.; Fox, M.B.; Boom, R.M.; Schutyser, M.A.I.

2014-01-01

Knowledge about moisture diffusivity in solid matrices is a key for understanding drying behaviour of for example probiotic or enzymatic formulations. This paper presents an experimental procedure to determine moisture diffusivity on the basis of thin film drying and gravimetric analysis in a

Investigation of gamma-ray sensitivity of neutron detectors based on thin converter films

Energy Technology Data Exchange (ETDEWEB)

Khaplanov, A; Hall-Wilton, R [European Spallation Source, P.O Box 176, SE-22100 Lund (Sweden); Piscitelli, F; Buffet, J-C; Clergeau, J-F; Correa, J; Esch, P van; Ferraton, M; Guerard, B [Institute Laue Langevin, Rue Jules Horowitz, FR-38042 Grenoble (France)

2013-10-15

Currently, many detector technologies for thermal neutron detection are in development in order to lower the demand for the rare {sup 3}He gas. Gas detectors with solid thin film neutron converters readout by gas proportional counter method have been proposed as an appropriate choice for applications where large area coverage is necessary. In this paper, we investigate the probability for {gamma}-rays to generate a false count in a neutron measurement. Simulated results are compared to measurement with {sup 10}B thin film prototypes and a {sup 3}He detector. It is demonstrated that equal {gamma}-ray rejection to that of {sup 3}He tubes is achieved with the new technology. The arguments and results presented here are also applicable to gas detectors with converters other than solid {sup 10}B layers, such as {sup 6}Li layers and {sup 10}BF{sub 3} gas.

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...

Thermal conductivity model for nanoporous thin films

Science.gov (United States)

Huang, Congliang; Zhao, Xinpeng; Regner, Keith; Yang, Ronggui

2018-03-01

Nanoporous thin films have attracted great interest because of their extremely low thermal conductivity and potential applications in thin thermal insulators and thermoelectrics. Although there are some numerical and experimental studies about the thermal conductivity of nanoporous thin films, a simplified model is still needed to provide a straightforward prediction. In this paper, by including the phonon scattering lifetimes due to film thickness boundary scattering, nanopore scattering and the frequency-dependent intrinsic phonon-phonon scattering, a fitting-parameter-free model based on the kinetic theory of phonon transport is developed to predict both the in-plane and the cross-plane thermal conductivities of nanoporous thin films. With input parameters such as the lattice constants, thermal conductivity, and the group velocity of acoustic phonons of bulk silicon, our model shows a good agreement with available experimental and numerical results of nanoporous silicon thin films. It illustrates that the size effect of film thickness boundary scattering not only depends on the film thickness but also on the size of nanopores, and a larger nanopore leads to a stronger size effect of the film thickness. Our model also reveals that there are different optimal structures for getting the lowest in-plane and cross-plane thermal conductivities.

Epitaxial thin film growth of LiH using a liquid-Li atomic template

International Nuclear Information System (INIS)

Oguchi, Hiroyuki; Ikeshoji, Tamio; Orimo, Shin-ichi; Ohsawa, Takeo; Shiraki, Susumu; Hitosugi, Taro; Kuwano, Hiroki

2014-01-01

We report on the synthesis of lithium hydride (LiH) epitaxial thin films through the hydrogenation of a Li melt, forming abrupt LiH/MgO interface. Experimental and first-principles molecular dynamics studies reveal a comprehensive microscopic picture of the crystallization processes, which sheds light on the fundamental atomistic growth processes that have remained unknown in the vapor-liquid-solid method. We found that the periodic structure that formed, because of the liquid-Li atoms at the film/MgO-substrate interface, serves as an atomic template for the epitaxial growth of LiH crystals. In contrast, films grown on the Al 2 O 3 substrates indicated polycrystalline films with a LiAlO 2 secondary phase. These results and the proposed growth process provide insights into the preparation of other alkaline metal hydride thin films on oxides. Further, our investigations open the way to explore fundamental physics and chemistry of metal hydrides including possible phenomena that emerge at the heterointerfaces of metal hydrides

PREFACE: 15th International Conference on Thin Films (ICTF-15)

Science.gov (United States)

Takai, Osamu; Saito, Nagahiro; Zettsu, Nobuyuki; Cho, Sung-Pyo; Terashima, Chiaki; Ueno, Tomonaga; Sakai, Osamu; Miyazaki, Seiichi; Yoshimura, Kazuki; Akamatsu, Kensuke; Ito, Takahiro; Yogo, Toshinobu; Inoue, Yasushi; Ohtake, Naoto; Yoshida, Tsukasa; Tosa, Masahiro; Takai, Madoka; Fujiwara, Yasufumi; Matsuda, Naoki; Teshima, Katsuya; Seki, Takahiro; Matsunaga, Katsuyuki; Fujita, Daisuke

2013-03-01

The International Conference on Thin Films is the most established conference for all researchers and persons interested in thin films and coatings. It is one of the tri-annual conference series endorsed and co-organized by the Thin Film Division of the International Union for Vacuum Science, Technique and Applications (IUVSTA), a union of national member societies whose role is to stimulate international collaboration in the fields of vacuum science, techniques and applications and related multi-disciplinary topics including solid-vacuum and other interfaces. The 15th International Conference on Thin Films (ICTF-15) is organized by The Vacuum Society of Japan (VSJ) and held at Kyoto TERRSA in Kyoto, Japan on 8-11 November 2011, following the 14th International Conference on Thin Films (ICTF-14), which was held in Ghent, Belgium in 2008. Thin films and coatings are daily becoming increasingly important in the fields of various industries. This International Conference provides a multi-disciplinary forum for recent advances in basic research, development and applications of thin films and coatings. This conference will present a unique opportunity for researchers, engineers and managers to acquire new knowledge of thin films and coatings. We hope that our understanding on thin films and coatings will be deepened through this conference. The conference site, 'Kyoto TERRSA' is located in the historical heart of the old capital Kyoto. Kyoto is an ancient city with a 1200-year history. It was established as Japan's capital under the name 'Heian-kyo' in the year 794. Although many transformations have taken place over the years, Kyoto has always embraced the most advanced standards of the times. It has greatly contributed to the nation's industrial, economic and cultural development. The dauntless spirit of leadership of Kyoto's past as a capital city is still felt here today. Kyoto also preserves the beloved examples of its culture as testimonials of time. This is shown

Photoinduced hydrophobic surface of graphene oxide thin films

International Nuclear Information System (INIS)

Zhang Xiaoyan; Song Peng; Cui Xiaoli

2012-01-01

Graphene oxide (GO) thin films were deposited on transparent conducting oxide substrates and glass slides by spin coating method at room temperature. The wettability of GO thin films before and after ultraviolet (UV) irradiation was characterized with water contact angles, which increased from 27.3° to 57.6° after 3 h of irradiation, indicating a photo-induced hydrophobic surface. The UV–vis absorption spectra, Raman spectroscopy, X-ray photoelectron spectroscopy, and conductivity measurements of GO films before and after UV irradiation were taken to study the mechanism of photoinduced hydrophobic surface of GO thin films. It is demonstrated that the photoinduced hydrophobic surface is ascribed to the elimination of oxygen-containing functional groups on GO molecules. This work provides a simple strategy to control the wettability properties of GO thin films by UV irradiation. - Highlights: ► Photoinduced hydrophobic surface of graphene oxide thin films has been demonstrated. ► Elimination of oxygen-containing functional groups in graphene oxide achieved by UV irradiation. ► We provide novel strategy to control surface wettability of GO thin films by UV irradiation.

Optical thin film deposition

International Nuclear Information System (INIS)

Macleod, H.A.

1979-01-01

The potential usefulness in the production of optical thin-film coatings of some of the processes for thin film deposition which can be classified under the heading of ion-assisted techniques is examined. Thermal evaporation is the process which is virtually universally used for this purpose and which has been developed to a stage where performance is in almost all respects high. Areas where further improvements would be of value, and the possibility that ion-assisted deposition might lead to such improvements, are discussed. (author)

Hydrogen absorption in thin ZnO films prepared by pulsed laser deposition

Czech Academy of Sciences Publication Activity Database

Melikhova, O.; Čížek, J.; Lukáč, F.; Vlček, M.; Novotný, Michal; Bulíř, Jiří; Lančok, Ján; Anwand, W.; Brauer, G.; Connolly, J.; McCarthy, E.; Krishnamurthy, S.; Mosnier, J.-P.

2013-01-01

Roč. 580, suppl. 1 (2013), S40-S43 ISSN 0925-8388 R&D Projects: GA ČR(CZ) GAP108/11/0958 Institutional support: RVO:68378271 Keywords : defects * hydrogen * positron annihilation * thin films * ZnO Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.726, year: 2013

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...

Reflection of circularly polarized light and the effect of particle distribution on circular dichroism in evaporation induced self-assembled cellulose nanocrystal thin films

Directory of Open Access Journals (Sweden)

D. Hewson

2017-06-01

Full Text Available Evaporation induced self-assembled (EISA thin films of cellulose nanocrystals (CNCs have shown great potential for displaying structural colour across the visible spectrum. They are believed primarily to reflect left handed circularly polarised (LCP light due to their natural tendency to form structures comprising left handed chirality. Accordingly the fabrication of homogenously coloured CNC thin films is challenging. Deposition of solid material towards the edge of a dried droplet, via the coffee-stain effect, is one such difficulty in achieving homogenous colour across CNC films. These effects are most easily observed in films prepared from droplets where observable reflection of visible light is localised around the edge of the dry film. We report here, the observation of both left and right hand circularly polarised (LCP/RCP light in reflection from distinct separate regions of CNC EISA thin films and we elucidate how these reflections are dependent on the distribution of CNC material within the EISA thin film. Optical models of reflection are presented which are based on structures revealed using high resolution transmission electron microscopy (TEM images of film cross sections. We have also employed spectroscopic characterisation techniques to evaluate the distribution of solid CNC material within a selection of CNC EISA thin films and we have correlated this distribution with polarised light spectra collected from each film. We conclude that film regions from which RCP light was reflected were associated with lower CNC concentrations and thicker film regions.

Application of V2O5 thin films deposited by laser ablation in micron batteries of solid state

International Nuclear Information System (INIS)

Escobar A, L.; Camps, E.; Haro P, E.; Camacho L, M.A.; Julien, C.

2001-01-01

The obtained results from synthesizing V 2 O 5 thin films by laser ablation are presented. Depending on the deposit conditions V 2 O 5 thin films have been grown as amorphous as a crystalline ones with preferential orientation. The results of the electrochemical characterization of one of the synthesized layers are presented when being manufactured joint with it a micron battery. (Author)

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

Combination of short-length TiO_2 nanorod arrays and compact PbS quantum-dot thin films for efficient solid-state quantum-dot-sensitized solar cells

International Nuclear Information System (INIS)

Zhang, Zhengguo; Shi, Chengwu; Chen, Junjun; Xiao, Guannan; Li, Long

2017-01-01

Graphical abstract: The TiO_2 nanorod array with the length of 600 nm, the diameter of 20 nm, the areal density of 500 μm"−"2 was successfully prepared. The compact PbS quantum-dot thin film was firstly obtained on the TiO_2 nanorod array by spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol. The photoelectric conversion efficiency (PCE) of the compact PbS quantum-dot thin film sensitized solar cells achieved 4.10% using spiro-OMeTAD as a hole transporting layer, while the PCE of the PbS quantum-dot sensitized solar cells was only 0.54%. - Highlights: • Preparation of TiO_2 nanorod arrays with the length of 600 nm, diameter of 20 nm. • The compact PbS QD thin film and short-length TiO_2 nanorod array were combined. • EDT addition improved PbS nanoparticle coverage and photovoltaic performance. • The compact PbS QD thin film sensitized solar cell achieved the PCE of 4.10%. - Abstract: Considering the balance of the hole diffusion length and the loading quantity of quantum-dots, the rutile TiO_2 nanorod array with the length of 600 nm, the diameter of 20 nm, and the areal density of 500 μm"−"2 is successfully prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 105 min. The compact PbS quantum-dot thin film on the TiO_2 nanorod array is firstly obtained by the spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol (EDT). The result reveals that the strong interaction between lead and EDT is very important to control the crystallite size of PbS quantum-dots and obtain the compact PbS quantum-dot thin film on the TiO_2 nanorod array. The all solid-state sensitized solar cell with the combination of the short-length, high-density TiO_2 nanorod array and the compact PbS quantum-dot thin film achieves the photoelectric conversion efficiency of 4.10%, along with an open

Characterization of thin films of the solid electrolyte Li(x)Mg(1-2x)Al(2+x)O4 (x = 0, 0.05, 0.15, 0.25).

Science.gov (United States)

Put, Brecht; Vereecken, Philippe M; Mees, Maarten J; Rosciano, Fabio; Radu, Iuliana P; Stesmans, Andre

2015-11-21

RF-sputtered thin films of spinel Li(x)Mg(1-2x)Al(2+x)O4 were investigated for use as solid electrolyte. The usage of this material can enable the fabrication of a lattice matched battery stack, which is predicted to lead to superior battery performance. Spinel Li(x)Mg(1-2x)Al(2+x)O4 thin films, with stoichiometry (x) ranging between 0 and 0.25, were formed after a crystallization anneal as shown by X-ray diffraction and transmission electron microscopy. The stoichiometry of the films was evaluated by elastic recoil detection and Rutherford backscattering and found to be slightly aluminum rich. The excellent electronic insulation properties were confirmed by both current-voltage measurements as well as by copper plating tests. The electrochemical stability window of the material was probed using cyclic voltammetry. Lithium plating and stripping was observed together with the formation of a Li-Pt alloy, indicating that Li-ions passed through the film. This observation contradicted with impedance measurements at open circuit potential, which showed no apparent Li-ion conductivity of the film. Impedance spectroscopy as a function of potential showed the occurrence of Li-ion intercalation into the Li(x)Mg(1-2x)Al(2+x)O4 layers. When incorporating Li-ions in the material the ionic conductivity can be increased by 3 orders of magnitude. Therefore it is anticipated that the response of Li(x)Mg(1-2x)Al(2+x)O4 is more adequate for a buffer layer than as the solid electrolyte.

Piezoelectric MEMS: Ferroelectric thin films for MEMS applications

Science.gov (United States)

Kanno, Isaku

2018-04-01

In recent years, piezoelectric microelectromechanical systems (MEMS) have attracted attention as next-generation functional microdevices. Typical applications of piezoelectric MEMS are micropumps for inkjet heads or micro-gyrosensors, which are composed of piezoelectric Pb(Zr,Ti)O3 (PZT) thin films and have already been commercialized. In addition, piezoelectric vibration energy harvesters (PVEHs), which are regarded as one of the key devices for Internet of Things (IoT)-related technologies, are promising future applications of piezoelectric MEMS. Significant features of piezoelectric MEMS are their simple structure and high energy conversion efficiency between mechanical and electrical domains even on the microscale. The device performance strongly depends on the function of the piezoelectric thin films, especially on their transverse piezoelectric properties, indicating that the deposition of high-quality piezoelectric thin films is a crucial technology for piezoelectric MEMS. On the other hand, although the difficulty in measuring the precise piezoelectric coefficients of thin films is a serious obstacle in the research and development of piezoelectric thin films, a simple unimorph cantilever measurement method has been proposed to obtain precise values of the direct or converse transverse piezoelectric coefficient of thin films, and recently this method has become to be the standardized testing method. In this article, I will introduce fundamental technologies of piezoelectric thin films and related microdevices, especially focusing on the deposition of PZT thin films and evaluation methods for their transverse piezoelectric properties.

Preparation of cellulose nitrate films using a spinning disc for solid state nuclear track detection (SSNTD) applications

International Nuclear Information System (INIS)

Raghunath, B.; Iyer, M.R.; Samant, S.D.

1995-01-01

Solid state nuclear track detectors (SSNTD) are widely used in the detection and measurement of ionizing particles. Cellulose nitrate (CN) films are commonly used as SSNTD for the measurement of radon/thoron gases and their decay products. A simple method for making uniform thin CN films of various thickness has been developed. Performance of these films is compared with commercially available film. (Author)

Preparation of cellulose nitrate films using a spinning disc for solid state nuclear track detection (SSNTD) applications

Energy Technology Data Exchange (ETDEWEB)

Raghunath, B.; Iyer, M.R. [Bhabha Atomic Research Centre, Bombay (India); Samant, S.D. [Bombay Univ. (India). Dept. of Chemical Technology

1995-01-01

Solid state nuclear track detectors (SSNTD) are widely used in the detection and measurement of ionizing particles. Cellulose nitrate (CN) films are commonly used as SSNTD for the measurement of radon/thoron gases and their decay products. A simple method for making uniform thin CN films of various thickness has been developed. Performance of these films is compared with commercially available film. (Author).

MATERIAL AND PROCESS DEVELOPMENT LEADING TO ECONOMICAL HIGH-PERFORMANCE THIN-FILM SOLID OXIDE FUEL CELLS. Final Technical Report (October 2000 - December 2003)

International Nuclear Information System (INIS)

Jie Guan; Nguyen Minh

2003-01-01

This report summarizes the results of the work conducted under the program: ''Material and Process Development Leading to Economical High-Performance Thin-Film Solid Oxide Fuel Cells'' under contract number DE-AC26-00NT40711. The program goal is to advance materials and processes that can be used to produce economical, high-performance solid oxide fuel cells (SOFC) capable of achieving extraordinary high power densities at reduced temperatures. Under this program, anode-supported thin electrolyte based on lanthanum gallate (LSMGF) has been developed using tape-calendering process. The fabrication parameters such as raw materials characteristics, tape formulations and sintering conditions have been evaluated. Dense anode supported LSGMF electrolytes with thickness range of 10-50 micron have been fabricated. High performance cathode based on Sr 0.5 Sm 0.5 CoO 3 (SSC) has been developed. Polarization of ∼0.23 ohm-cm 2 has been achieved at 600 C with Sr 0.5 Sm 0.5 CoO 3 cathode. The high-performance SSC cathode and thin gallate electrolyte have been integrated into single cells and cell performance has been characterized. Tested cells to date generally showed low performance because of low cell OCVs and material interactions between NiO in the anode and lanthanum gallate electrolyte

Grain Boundaries Act as Solid Walls for Charge Carrier Diffusion in Large Crystal MAPI Thin Films.

Science.gov (United States)

Ciesielski, Richard; Schäfer, Frank; Hartmann, Nicolai F; Giesbrecht, Nadja; Bein, Thomas; Docampo, Pablo; Hartschuh, Achim

2018-03-07

Micro- and nanocrystalline methylammonium lead iodide (MAPI)-based thin-film solar cells today reach power conversion efficiencies of over 20%. We investigate the impact of grain boundaries on charge carrier transport in large crystal MAPI thin films using time-resolved photoluminescence (PL) microscopy and numerical model calculations. Crystal sizes in the range of several tens of micrometers allow for the spatially and time resolved study of boundary effects. Whereas long-ranged diffusive charge carrier transport is observed within single crystals, no detectable diffusive transport occurs across grain boundaries. The observed PL transients are found to crucially depend on the microscopic geometry of the crystal and the point of observation. In particular, spatially restricted diffusion of charge carriers leads to slower PL decay near crystal edges as compared to the crystal center. In contrast to many reports in the literature, our experimental results show no quenching or additional loss channels due to grain boundaries for the studied material, which thus do not negatively affect the performance of the derived thin-film devices.

Growth process and structure of Er/Si(100) thin film

International Nuclear Information System (INIS)

Fujii, S.; Michishita, Y.; Miyamae, N.; Suto, H.; Honda, S.; Okado, H.; Oura, K.; Katayama, M.

2006-01-01

The solid-phase reactive epitaxial growth processes and structures of Er/Si(100) thin films were investigated by coaxial impact-collision ion scattering spectroscopy (CAICISS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The as-deposited Er film grown at room temperature was transformed into crystalline rectangular-shaped islands after annealing at 900 deg. C. These islands have a hexagonal AlB 2 -type structure and the epitaxial relationship is determined to be ErSi 2 (011-bar0)[0001]//Si(100)[011-bar]. It has been revealed that the surface of the Er silicide island is terminated with an Er plane

Mn-doped Ge self-assembled quantum dots via dewetting of thin films

Energy Technology Data Exchange (ETDEWEB)

Aouassa, Mansour, E-mail: mansour.aouassa@yahoo.fr [LMON, Faculté des Sciences de Monastir, Avenue de l’environnement Monastir 5019 (Tunisia); Jadli, Imen [LMON, Faculté des Sciences de Monastir, Avenue de l’environnement Monastir 5019 (Tunisia); Bandyopadhyay, Anup [Department of Mechanical Engineering, Texas A& M University, College Station, TX 77843 (United States); Kim, Sung Kyu [Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Yuseong-daero 1689-gil, Yuseong-gu, Daejeon (Korea, Republic of); Department of Materials Science and Engineering, KAIST 291 Daehak-ro, Yuseong-gu, Daejeon (Korea, Republic of); Karaman, Ibrahim [Department of Mechanical Engineering, Texas A& M University, College Station, TX 77843 (United States); Lee, Jeong Yong [Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Yuseong-daero 1689-gil, Yuseong-gu, Daejeon (Korea, Republic of); Department of Materials Science and Engineering, KAIST 291 Daehak-ro, Yuseong-gu, Daejeon (Korea, Republic of)

2017-03-01

Highlights: • We report the new fabrication approach for producing a self- assembled Mn dpoed Ge quantum dots (QDs) on SiO{sub 2} thin film with a Curie temperature above room temperature. These magnetic QDs are crystalline, monodisperse and have a well-defined shape and a controlled size. The investigation opens new routes for elaboration of self-assembled magnetic nanocrystals - Abstract: In this study, we demonstrate an original elaboration route for producing a Mn-doped Ge self-assembled quantum dots on SiO{sub 2} thin layer for MOS structure. These magnetic quantum dots are elaborated using dewetting phenomenon at solid state by Ultra-High Vacuum (UHV) annealing at high temperature of an amorphous Ge:Mn (Mn: 40%) nanolayer deposed at very low temperature by high-precision Solid Source Molecular Beam Epitaxy on SiO{sub 2} thin film. The size of quantum dots is controlled with nanometer scale precision by varying the nominal thickness of amorphous film initially deposed. The magnetic properties of the quantum-dots layer have been investigated by superconducting quantum interference device (SQUID) magnetometry. Atomic force microscopy (AFM), x-ray energy dispersive spectroscopy (XEDS) and transmission electron microscopy (TEM) were used to examine the nanostructure of these materials. Obtained results indicate that GeMn QDs are crystalline, monodisperse and exhibit a ferromagnetic behavior with a Curie temperature (TC) above room temperature. They could be integrated into spintronic technology.

Raman scattering study of phonons in Bi-based superconductor thin films

International Nuclear Information System (INIS)

Mejia-Garcia, C.; Diaz-Valdes, E.; Contreras-Puente, G.; Lopez-Lopez, J.L.; Jergel, M.; Morales, A.

2004-01-01

Raman spectra were obtained from samples of Bi-Pb-Sr-Ca-Cu-O (BPSCCO) thin films after varying several growth parameters, such as covering material, annealing time (t R ), annealing temperature (T R ), and nominal lead content (x). Thin films with the nominal composition Bi 1.4 Pb x Sr 2 Ca 2 Cu 3 O δ were grown on MgO substrates by a spray pyrolysis technique, followed by a solid state reaction. The results of Raman scattering measurements at room temperature show a series of vibrational optical modes within the range 300-900 cm -1 . The assignment of these modes was made by involving mainly the 2212 and 2223 phases and was confirmed by both X-ray diffraction and resistance in dependence of the temperature (R-T) measurements as well

Nanometric thin film membranes manufactured on square meter scale: ultra-thin films for CO 2 capture

KAUST Repository

Yave, Wilfredo

2010-09-01

Miniaturization and manipulation of materials at nanometer scale are key challenges in nanoscience and nanotechnology. In membrane science and technology, the fabrication of ultra-thin polymer films (defect-free) on square meter scale with uniform thickness (<100 nm) is crucial. By using a tailor-made polymer and by controlling the nanofabrication conditions, we developed and manufactured defect-free ultra-thin film membranes with unmatched carbon dioxide permeances, i.e. >5 m3 (STP) m-2 h -1 bar-1. The permeances are extremely high, because the membranes are made from a CO2 philic polymer material and they are only a few tens of nanometers thin. Thus, these thin film membranes have potential application in the treatment of large gas streams under low pressure like, e.g., carbon dioxide separation from flue gas. © 2010 IOP Publishing Ltd.

Thin film bismuth iron oxides useful for piezoelectric devices

Science.gov (United States)

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.

Solid-State Thin-Film Supercapacitors with Ultrafast Charge/Discharge Based on N-Doped-Carbon-Tubes/Au-Nanoparticles-Doped-MnO2 Nanocomposites.

Science.gov (United States)

Lv, Qiying; Wang, Shang; Sun, Hongyu; Luo, Jun; Xiao, Jian; Xiao, JunWu; Xiao, Fei; Wang, Shuai

2016-01-13

Although carbonaceous materials possess long cycle stability and high power density, their low-energy density greatly limits their applications. On the contrary, metal oxides are promising pseudocapacitive electrode materials for supercapacitors due to their high-energy density. Nevertheless, poor electrical conductivity of metal oxides constitutes a primary challenge that significantly limits their energy storage capacity. Here, an advanced integrated electrode for high-performance pseudocapacitors has been designed by growing N-doped-carbon-tubes/Au-nanoparticles-doped-MnO2 (NCTs/ANPDM) nanocomposite on carbon fabric. The excellent electrical conductivity and well-ordered tunnels of NCTs together with Au nanoparticles of the electrode cause low internal resistance, good ionic contact, and thus enhance redox reactions for high specific capacitance of pure MnO2 in aqueous electrolyte, even at high scan rates. A prototype solid-state thin-film symmetric supercapacitor (SSC) device based on NCTs/ANPDM exhibits large energy density (51 Wh/kg) and superior cycling performance (93% after 5000 cycles). In addition, the asymmetric supercapacitor (ASC) device assembled from NCTs/ANPDM and Fe2O3 nanorods demonstrates ultrafast charge/discharge (10 V/s), which is among the best reported for solid-state thin-film supercapacitors with both electrodes made of metal oxide electroactive materials. Moreover, its superior charge/discharge behavior is comparable to electrical double layer type supercapacitors. The ASC device also shows superior cycling performance (97% after 5000 cycles). The NCTs/ANPDM nanomaterial demonstrates great potential as a power source for energy storage devices.

On mobility of ions in thin films in liquid substrates

International Nuclear Information System (INIS)

Matveev, Yu.A.

1984-01-01

The problem of energy dissipation by emission of ripplons is solved for an ion moving in the media with two interfaces (films on solid and liquid substrates), taking into account the Van der Waals interaction. It is shown that in contrast to the earlier considered case of solid substrate where the action of the Van der Waals forces causes only renormalization of the free fall acceleration, in the vase of liquid substrate the influence of these forces is much more complicated. In addition to renormalization of the amplitude of the emitted surface wave and change of the velocity threshold after which the wave mechanism is effective, in sufficiently thin film, where modes are ''intersected'' the analytical expressions for mobility are also significantly modified. In real experimental environments consideration of all the factors mentioned leads as a rule to higher ion mobility

Tools to synthesize the learning of thin films

International Nuclear Information System (INIS)

Rojas, Roberto; Fuster, Gonzalo; Sluesarenko, Viktor

2011-01-01

After a review of textbooks written for undergraduate courses in physics, we have found that discussions on thin films are mostly incomplete. They consider the reflected and not the transmitted light for two instead of the four types of thin films. In this work, we complement the discussion in elementary textbooks, by analysing the phase differences required to match the conditions for constructive and destructive interference, in the reflected and transmitted light in four types of thin films. We consider thin films with varied sequences in the refractive index, which we identify as barriers, wells and stairs (up and down). Also, we use the conservation of energy in order to understand the complementary colour fringes observed in the reflected and transmitted light through thin films. We analyse systematically the phase changes by introducing a phase table and we synthesize the results in a circular diagram matching 16 physical situations of interference and their corresponding conditions on the film thickness. The phase table and the circular diagram are a pair of tools easily assimilated by students, and useful to organize, analyse and activate the knowledge about thin films.

Low-cost flexible thin-film detector for medical dosimetry applications.

Science.gov (United States)

Zygmanski, P; Abkai, C; Han, Z; Shulevich, Y; Menichelli, D; Hesser, J

2014-03-06

detector sensors in a Solid Water phantom under various irradiation conditions. Different factors are considered in characterization of the device attributes: energies (80 kVp, 130 kVp, 6 MV, 15 MV), dose rates (different ms × mA, 100-600 MU/min), total doses (0.1 cGy-500 cGy), depths (0.5 cm-20 cm), irradiation angles with respect to the detector surface (0°-180°), and IMRT tests (closed MLC, sweeping gap). The detector response to MV radiation is both linear with total dose (~1-400 cGy) and independent of dose rate (100-600 Mu/min). The sensitivity per unit area of thin-film sensors is lower than for aSi flat-panel detectors, but sufficient to acquire stable and accurate signals during irradiations. The proposed thin-film photodiode system has properties which make it promising for clinical dosimetry. Due to the mechanical flexibility of each sensor and readout electronics, low-cost, and wireless data acquisition, it could be considered for quality assurance (e.g., IMRT, mechanical linac QA), as well as real-time dose monitoring in challenging setup configurations, including large area and 3D detection (multiple planes or curved surfaces).

Thin Solid Oxide Cell

DEFF Research Database (Denmark)

2010-01-01

The present invention relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material, at least one metal and a catalyst...... material, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same. The present invention also relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous...... cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material and a catalyst material, wherein the electrolyte material is doper zirconia, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same...

An introduction to fast dissolving oral thin film drug delivery systems: a review.

Science.gov (United States)

Kathpalia, Harsha; Gupte, Aasavari

2013-12-01

Many pharmaceutical companies are switching their products from tablets to fast dissolving oral thin films (OTFs). Films have all the advantages of tablets (precise dosage, easy administration) and those of liquid dosage forms (easy swallowing, rapid bioavailability). Statistics have shown that four out of five patients prefer orally disintegrating dosage forms over conventional solid oral dosages forms. Pediatric, geriatric, bedridden, emetic patients and those with Central Nervous System disorders, have difficulty in swallowing or chewing solid dosage forms. Many of these patients are non-compliant in administering solid dosage forms due to fear of choking. OTFs when placed on the tip or the floor of the tongue are instantly wet by saliva. As a result, OTFs rapidly hydrate and then disintegrate and/or dissolve to release the medication for local and/or systemic absorption. This technology provides a good platform for patent non- infringing product development and for increasing the patent life-cycle of the existing products. The application of fast dissolving oral thin films is not only limited to buccal fast dissolving system, but also expands to other applications like gastroretentive, sublingual delivery systems. This review highlights the composition including the details of various types of polymers both natural and synthetic, the different types of manufacturing techniques, packaging materials and evaluation tests for the OTFs.

Resistivity of thiol-modified gold thin films

International Nuclear Information System (INIS)

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

2014-01-01

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

Resistivity of thiol-modified gold thin films

Energy Technology Data Exchange (ETDEWEB)

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

2014-11-03

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

Adsorption properties of Mg-Al layered double hydroxides thin films grown by laser based techniques

Energy Technology Data Exchange (ETDEWEB)

Matei, A., E-mail: andreeapurice@nipne.ro [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Str., 77125 Bucharest, Magurele (Romania); Birjega, R.; Vlad, A.; Filipescu, M.; Nedelcea, A.; Luculescu, C. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Str., 77125 Bucharest, Magurele (Romania); Zavoianu, R.; Pavel, O.D. [University of Bucharest, Faculty of Chemistry, Department of Chemical Technology and Catalysis, 4-12 Regina Elisabeta Bd., Bucharest (Romania); Dinescu, M. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Str., 77125 Bucharest, Magurele (Romania)

2012-09-15

Highlights: Black-Right-Pointing-Pointer Laser techniques MAPLE and PLD can successfully be used to produce LDHs thin films. Black-Right-Pointing-Pointer Hydration treatments of the PLD and MAPLE deposited films lead to the LDH reconstruction effect. Black-Right-Pointing-Pointer The Ni retention from aqueous solution occurs in the films via a dissolution-reconstruction mechanism. Black-Right-Pointing-Pointer The films are suitable for applications in remediation of contaminated drinking water or waste waters. - Abstract: Powdered layered double hydroxides (LDHs) have been widely studied due to their applications as catalysts, anionic exchangers or host materials for inorganic and/or organic molecules. Assembling nano-sized LDHs onto flat solid substrates forming thin films is an expanding area of research due to the prospects of novel applications as sensors, corrosion-resistant coatings, components in optical and magnetic devices. Continuous and adherent thin films were grown by laser techniques (pulsed laser deposition - PLD and matrix assisted pulsed laser evaporation - MAPLE) starting from targets of Mg-Al LDHs. The capacity of the grown thin films to retain a metal (Ni) from contaminated water has been also explored. The thin films were immersed in an Ni(NO{sub 3}){sub 2} aqueous solutions with Ni concentrations of 10{sup -3}% (w/w) (1 g/L) and 10{sup -4}% (w/w) (0.1 g/L), respectively. X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM) combined with energy dispersive X-ray analysis (EDX) were the techniques used to characterize the prepared materials.

Profilometry of thin films on rough substrates by Raman spectroscopy

Czech Academy of Sciences Publication Activity Database

Ledinský, Martin; Paviet-Salomon, B.; Vetushka, Aliaksi; Geissbühler, J.; Tomasi, A.; Despeisse, M.; De Wolf, S.; Ballif, C.; Fejfar, Antonín

2016-01-01

Roč. 6, Dec (2016), s. 1-7, č. článku 37859. ISSN 2045-2322 R&D Projects: GA MŠk LM2015087; GA ČR GA14-15357S EU Projects: European Commission(XE) 727523 NextBase Institutional support: RVO:68378271 Keywords : solar cells * surfaces * interfaces and thin films * two-dimensional materials Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.259, year: 2016

Thin film removal mechanisms in ns-laser processing of photovoltaic materials

International Nuclear Information System (INIS)

Bovatsek, J.; Tamhankar, A.; Patel, R.S.; Bulgakova, N.M.; Bonse, J.

2010-01-01

The removal of thin films widely used in photovoltaics (amorphous silicon, tin oxide, zinc oxide, aluminum, and molybdenum) is studied experimentally using multi-kHz Q-switched solid-state lasers at 532 nm and 1064 nm wavelengths. The processing ('scribing') is performed through the film-supporting glass plate at scribing speeds of the order of m/s. The dependence of the film removal threshold on the laser pulse duration (8 ns to 40 ns) is investigated and the results are complemented by a multi-layer thermal model used for numerical simulations of the laser-induced spatio-temporal temperature field within the samples. Possible film removal mechanisms are discussed upon consideration of optical, geometrical, thermal and mechanical properties of the layers.

Thermodynamic and kinetic anisotropies in octane thin films

International Nuclear Information System (INIS)

Haji-Akbari, Amir; Debenedetti, Pablo G.

2015-01-01

Confinement breaks the translational symmetry of materials, making all thermodynamic and kinetic quantities functions of position. Such symmetry breaking can be used to obtain configurations that are not otherwise accessible in the bulk. Here, we use computer simulations to explore the effect of substrate-liquid interactions on thermodynamic and kinetic anisotropies induced by a solid substrate. We consider n-octane nano-films that are in contact with substrates with varying degrees of attraction, parameterized by an interaction parameter ϵ S . Complete freezing of octane nano-films is observed at low temperatures, irrespective of ϵ S , while at intermediate temperatures, a frozen monolayer emerges at solid-liquid and vapor-liquid interfaces. By carefully inspecting the profiles of translational and orientational relaxation times, we confirm that the translational and orientational degrees of freedom are decoupled at these frozen monolayers. At sufficiently high temperatures, however, free interfaces and solid-liquid interfaces close to loose (low-ϵ S ) substrates undergo “pre-freezing,” characterized by mild peaks in several thermodynamic quantities. Two distinct dynamic regimes are observed at solid-liquid interfaces. The dynamics is accelerated in the vicinity of loose substrates, while sticky (high-ϵ S ) substrates decelerate dynamics, sometimes by as much as two orders of magnitude. These two distinct dynamical regimes have been previously reported by Haji-Akbari and Debenedetti [J. Chem. Phys. 141, 024506 (2014)] for a model atomic glass-forming liquid. We also confirm the existence of two correlations—proposed in the above-mentioned work—in solid-liquid subsurface regions of octane thin films, i.e., a correlation between atomic density and normal stress, and between atomic translational relaxation time and lateral stress. Finally, we inspect the ability of different regions of an octane film to explore the potential energy landscape by performing

Thermodynamic and kinetic anisotropies in octane thin films

Energy Technology Data Exchange (ETDEWEB)

Haji-Akbari, Amir; Debenedetti, Pablo G., E-mail: pdebene@exchange.princeton.edu [Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544 (United States)

2015-12-07

Confinement breaks the translational symmetry of materials, making all thermodynamic and kinetic quantities functions of position. Such symmetry breaking can be used to obtain configurations that are not otherwise accessible in the bulk. Here, we use computer simulations to explore the effect of substrate-liquid interactions on thermodynamic and kinetic anisotropies induced by a solid substrate. We consider n-octane nano-films that are in contact with substrates with varying degrees of attraction, parameterized by an interaction parameter ϵ{sub S}. Complete freezing of octane nano-films is observed at low temperatures, irrespective of ϵ{sub S}, while at intermediate temperatures, a frozen monolayer emerges at solid-liquid and vapor-liquid interfaces. By carefully inspecting the profiles of translational and orientational relaxation times, we confirm that the translational and orientational degrees of freedom are decoupled at these frozen monolayers. At sufficiently high temperatures, however, free interfaces and solid-liquid interfaces close to loose (low-ϵ{sub S}) substrates undergo “pre-freezing,” characterized by mild peaks in several thermodynamic quantities. Two distinct dynamic regimes are observed at solid-liquid interfaces. The dynamics is accelerated in the vicinity of loose substrates, while sticky (high-ϵ{sub S}) substrates decelerate dynamics, sometimes by as much as two orders of magnitude. These two distinct dynamical regimes have been previously reported by Haji-Akbari and Debenedetti [J. Chem. Phys. 141, 024506 (2014)] for a model atomic glass-forming liquid. We also confirm the existence of two correlations—proposed in the above-mentioned work—in solid-liquid subsurface regions of octane thin films, i.e., a correlation between atomic density and normal stress, and between atomic translational relaxation time and lateral stress. Finally, we inspect the ability of different regions of an octane film to explore the potential energy

Thermodynamic and kinetic anisotropies in octane thin films.

Science.gov (United States)

Haji-Akbari, Amir; Debenedetti, Pablo G

2015-12-07

Confinement breaks the translational symmetry of materials, making all thermodynamic and kinetic quantities functions of position. Such symmetry breaking can be used to obtain configurations that are not otherwise accessible in the bulk. Here, we use computer simulations to explore the effect of substrate-liquid interactions on thermodynamic and kinetic anisotropies induced by a solid substrate. We consider n-octane nano-films that are in contact with substrates with varying degrees of attraction, parameterized by an interaction parameter ϵS. Complete freezing of octane nano-films is observed at low temperatures, irrespective of ϵS, while at intermediate temperatures, a frozen monolayer emerges at solid-liquid and vapor-liquid interfaces. By carefully inspecting the profiles of translational and orientational relaxation times, we confirm that the translational and orientational degrees of freedom are decoupled at these frozen monolayers. At sufficiently high temperatures, however, free interfaces and solid-liquid interfaces close to loose (low-ϵS) substrates undergo "pre-freezing," characterized by mild peaks in several thermodynamic quantities. Two distinct dynamic regimes are observed at solid-liquid interfaces. The dynamics is accelerated in the vicinity of loose substrates, while sticky (high-ϵS) substrates decelerate dynamics, sometimes by as much as two orders of magnitude. These two distinct dynamical regimes have been previously reported by Haji-Akbari and Debenedetti [J. Chem. Phys. 141, 024506 (2014)] for a model atomic glass-forming liquid. We also confirm the existence of two correlations-proposed in the above-mentioned work-in solid-liquid subsurface regions of octane thin films, i.e., a correlation between atomic density and normal stress, and between atomic translational relaxation time and lateral stress. Finally, we inspect the ability of different regions of an octane film to explore the potential energy landscape by performing inherent

Towards a uniform and large-scale deposition of MoS2 nanosheets via sulfurization of ultra-thin Mo-based solid films.

Science.gov (United States)

Vangelista, Silvia; Cinquanta, Eugenio; Martella, Christian; Alia, Mario; Longo, Massimo; Lamperti, Alessio; Mantovan, Roberto; Basset, Francesco Basso; Pezzoli, Fabio; Molle, Alessandro

2016-04-29

Large-scale integration of MoS2 in electronic devices requires the development of reliable and cost-effective deposition processes, leading to uniform MoS2 layers on a wafer scale. Here we report on the detailed study of the heterogeneous vapor-solid reaction between a pre-deposited molybdenum solid film and sulfur vapor, thus resulting in a controlled growth of MoS2 films onto SiO2/Si substrates with a tunable thickness and cm(2)-scale uniformity. Based on Raman spectroscopy and photoluminescence, we show that the degree of crystallinity in the MoS2 layers is dictated by the deposition temperature and thickness. In particular, the MoS2 structural disorder observed at low temperature (<750 °C) and low thickness (two layers) evolves to a more ordered crystalline structure at high temperature (1000 °C) and high thickness (four layers). From an atomic force microscopy investigation prior to and after sulfurization, this parametrical dependence is associated with the inherent granularity of the MoS2 nanosheet that is inherited by the pristine morphology of the pre-deposited Mo film. This work paves the way to a closer control of the synthesis of wafer-scale and atomically thin MoS2, potentially extendable to other transition metal dichalcogenides and hence targeting massive and high-volume production for electronic device manufacturing.

One-dimensional analysis of the hydrodynamic and thermal characteristics of thin film flows including the hydraulic jump and rotation

Science.gov (United States)

Thomas, S.; Hankey, W.; Faghri, A.; Swanson, T.

1990-01-01

The flow of a thin liquid film with a free surface along a horizontal plane that emanates from a pressurized vessel is examined numerically. In one g, a hydraulic jump was predicted in both plane and radial flow, which could be forced away from the inlet by increasing the inlet Froude number or Reynolds number. In zero g, the hydraulic jump was not predicted. The effect of solid-body rotation for radial flow in one g was to 'wash out' the hydraulic jump and to decrease the film height on the disk. The liquid film heights under one g and zero g were equal under solid-body rotation because the effect of centrifugal force was much greater than that of the gravitational force. The heat transfer to a film on a rotating disk was predicted to be greater than that of a stationary disk because the liquid film is extremely thin and is moving with a very high velocity.

Beyond the Young-Laplace model for cluster growth during dewetting of thin films: effective coarsening exponents and the role of long range dewetting interactions.

Science.gov (United States)

Constantinescu, Adi; Golubović, Leonardo; Levandovsky, Artem

2013-09-01

Long range dewetting forces acting across thin films, such as the fundamental van der Waals interactions, may drive the formation of large clusters (tall multilayer islands) and pits, observed in thin films of diverse materials such as polymers, liquid crystals, and metals. In this study we further develop the methodology of the nonequilibrium statistical mechanics of thin films coarsening within continuum interface dynamics model incorporating long range dewetting interactions. The theoretical test bench model considered here is a generalization of the classical Mullins model for the dynamics of solid film surfaces. By analytic arguments and simulations of the model, we study the coarsening growth laws of clusters formed in thin films due to the dewetting interactions. The ultimate cluster growth scaling laws at long times are strongly universal: Short and long range dewetting interactions yield the same coarsening exponents. However, long range dewetting interactions, such as the van der Waals forces, introduce a distinct long lasting early time scaling behavior characterized by a slow growth of the cluster height/lateral size aspect ratio (i.e., a time-dependent Young angle) and by effective coarsening exponents that depend on cluster size. In this study, we develop a theory capable of analytically calculating these effective size-dependent coarsening exponents characterizing the cluster growth in the early time regime. Such a pronounced early time scaling behavior has been indeed seen in experiments; however, its physical origin has remained elusive to this date. Our theory attributes these observed phenomena to ubiquitous long range dewetting interactions acting across thin solid and liquid films. Our results are also applicable to cluster growth in initially very thin fluid films, formed by depositing a few monolayers or by a submonolayer deposition. Under this condition, the dominant coarsening mechanism is diffusive intercluster mass transport while the

Improvement in interfacial characteristics of low-voltage carbon nanotube thin-film transistors with solution-processed boron nitride thin films

Energy Technology Data Exchange (ETDEWEB)

Jeon, Jun-Young; Ha, Tae-Jun, E-mail: taejunha0604@gmail.com

2017-08-15

Highlights: • We demonstrate the potential of solution-processed boron nitride (BN) thin films for nanoelectronics. • Improved interfacial characteristics reduced the leakage current by three orders of magnitude. • The BN encapsulation improves all the device key metrics of low-voltage SWCNT-TFTs. • Such improvements were achieved by reduced interaction of interfacial localized states. - Abstract: In this article, we demonstrate the potential of solution-processed boron nitride (BN) thin films for high performance single-walled carbon nanotube thin-film transistors (SWCNT-TFTs) with low-voltage operation. The use of BN thin films between solution-processed high-k dielectric layers improved the interfacial characteristics of metal-insulator-metal devices, thereby reducing the current density by three orders of magnitude. We also investigated the origin of improved device performance in SWCNT-TFTs by employing solution-processed BN thin films as an encapsulation layer. The BN encapsulation layer improves the electrical characteristics of SWCNT-TFTs, which includes the device key metrics of linear field-effect mobility, sub-threshold swing, and threshold voltage as well as the long-term stability against the aging effect in air. Such improvements can be achieved by reduced interaction of interfacial localized states with charge carriers. We believe that this work can open up a promising route to demonstrate the potential of solution-processed BN thin films on nanoelectronics.

Characterization of nanocrystalline cadmium telluride thin films ...

Indian Academy of Sciences (India)

Unknown

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

Graphene oxide/carbon nanoparticle thin film based IR detector: Surface properties and device characterization

Directory of Open Access Journals (Sweden)

Farzana Aktar Chowdhury

2015-10-01

Full Text Available This work deals with the synthesis, characterization, and application of carbon nanoparticles (CNP adorned graphene oxide (GO nanocomposite materials. Here we mainly focus on an emerging topic in modern research field presenting GO-CNP nanocomposite as a infrared (IR radiation detector device. GO-CNP thin film devices were fabricated from liquid phase at ambient condition where no modifying treatments were necessary. It works with no cooling treatment and also for stationary objects. A sharp response of human body IR radiation was detected with time constants of 3 and 36 sec and radiation responsivity was 3 mAW−1. The current also rises for quite a long time before saturation. This work discusses state-of-the-art material developing technique based on near-infrared photon absorption and their use in field deployable instrument for real-world applications. GO-CNP-based thin solid composite films also offer its potentiality to be utilized as p-type absorber material in thin film solar cell, as well.

Graphene oxide/carbon nanoparticle thin film based IR detector: Surface properties and device characterization

Energy Technology Data Exchange (ETDEWEB)

Chowdhury, Farzana Aktar [Experimental Physics Division, Atomic Energy Centre, 4, Kazi Nazrul Islam Avenue, Dhaka-1000 (Bangladesh); Hossain, Mohammad Abul [Department of Chemistry, Faculty of Science, University of Dhaka, Dhaka-1000 (Bangladesh); Uchida, Koji; Tamura, Takahiro; Sugawa, Kosuke; Mochida, Tomoaki; Otsuki, Joe [College of Science and Technology, Nihon University, 1-8-14 Kanda Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Mohiuddin, Tariq [Department of Physics, College of Science, Sultan Qaboos University, Muscat (Oman); Boby, Monny Akter [Department of Physics, Faculty of Science, University of Dhaka, Dhaka-1000 (Bangladesh); Alam, Mohammad Sahabul, E-mail: msalam@ksu.edu.sa [Department of Physics, Faculty of Science, University of Dhaka, Dhaka-1000 (Bangladesh); Department of Chemical Engineering, College of Engineering & King Abdullah Institute for Nanotechnology, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia)

2015-10-15

This work deals with the synthesis, characterization, and application of carbon nanoparticles (CNP) adorned graphene oxide (GO) nanocomposite materials. Here we mainly focus on an emerging topic in modern research field presenting GO-CNP nanocomposite as a infrared (IR) radiation detector device. GO-CNP thin film devices were fabricated from liquid phase at ambient condition where no modifying treatments were necessary. It works with no cooling treatment and also for stationary objects. A sharp response of human body IR radiation was detected with time constants of 3 and 36 sec and radiation responsivity was 3 mAW{sup −1}. The current also rises for quite a long time before saturation. This work discusses state-of-the-art material developing technique based on near-infrared photon absorption and their use in field deployable instrument for real-world applications. GO-CNP-based thin solid composite films also offer its potentiality to be utilized as p-type absorber material in thin film solar cell, as well.

Optical characteristics of the thin-film scintillator detector

International Nuclear Information System (INIS)

Muga, L.; Burnsed, D.

1976-01-01

A study of the thin-film detector (TFD) was made in which various light guide and scintillator film support configurations were tested for efficiency of light coupling. Masking of selected portions of the photomultiplier (PM) tube face revealed the extent to which emitted light was received at the exposed PM surfaces. By blocking off selected areas of the scintillator film surface from direct view of the PM tube faces, a measure of the light-guiding efficiency of the film and its support could be estimated. The picture that emerges is that, as the light which is initially trapped in the thin film spreads radially outward from the ion entrance/exit point, it is scattered out of the film by minute imperfections. Optimum signals were obtained by a configuration in which the thin scintillator film was supported on a thin rectangular Celluloid frame inserted within a highly polished metal cylindrical sleeve

A simple visible light photo-assisted method for assembling and curing multilayer GO thin films

Energy Technology Data Exchange (ETDEWEB)

Pinheiro da Silva, Mauro Francisco, E-mail: mfps@usp.br [Escola Politécnica da Universidade de São Paulo, Departamento de Engenharia Metalúrgica e de Materiais, PMT-EPUSP e Departamento de Engenharia de Sistemas Eletrônicos, PSI-EPUSP, Av. Professor Mello Moraes, n° 2463, Cidade Universitária, CEP 05508-030, São Paulo, SP (Brazil); Pontifícia Universidade de São Paulo, Faculdade de Ciências Exatas e Tecnologia, Rua Marquês de Paranaguá, 111, CEP 01303-050, São Paulo, SP (Brazil); Oliveira, Débora Rose de [Instituto de Criminalística da Secretaria de Segurança do Estado de São Paulo, Núcleo de Química, Rua Moncorvo Filho, CEP 05507-060, São Paulo, SP (Brazil); Pontifícia Universidade de São Paulo, Faculdade de Ciências Exatas e Tecnologia, Rua Marquês de Paranaguá, 111, CEP 01303-050, São Paulo, SP (Brazil); and others

2015-09-01

A simple and efficient method for deposition of reduced graphene oxide (RGO) thin films onto arbitrary substrates is described. The present protocol consists in the application of radial compression to a thin layer of graphene oxide (GO) formed at the air–liquid interface of an ammoniacal dispersion of graphene oxide by continuous irradiation with visible light, that drives both the formation and curing of the film. Both infrared and near infrared luminescence spectroscopies were used for the proposition of a chemical mechanism in which the in situ singlet oxygen Δ{sup 1}O{sub 2}, generated by the photosensitization of molecular oxygen to visible light, initiates the formation and curing of the film. The GO and RGO films display Raman spectral signatures typical of graphene – based materials, with thickness of ca. 20 nm as evaluated by atomic force microscopy. The deposited films exhibited good transparency to visible light (max. 85%; 550 ± 2 nm), electrical resistivity equals to 14 ± 0.02 Ω m, sheet resistance equals to 5 kΩ sq{sup −1} with associated charge carrier mobility of 200 cm{sup 2}/V s. - Highlights: • Visible light photochemical assembly of self-supported graphene oxide thin films. • Graphene oxide photosensitizer for in situ production of singlet oxygen Δ{sup 1}O{sub 2}. • Δ{sup 1}O{sub 2}, as initiator of formation and curing of graphene oxide thin film. • Deposition of colloidal graphene oxide thin film by radial compression. • Deposition of graphene oxide thin film in arbitrary solid substrate.

Preparation of LiMn{sub 2}O{sub 4} cathode thin films for thin film lithium secondary batteries by a mist CVD process

Energy Technology Data Exchange (ETDEWEB)

Tadanaga, Kiyoharu, E-mail: tadanaga@chem.osakafu-u.ac.jp [Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, Sakai, Osaka, 599-8531 (Japan); Yamaguchi, Akihiro; Sakuda, Atsushi; Hayashi, Akitoshi; Tatsumisago, Masahiro [Department of Applied Chemistry, Graduate School of Engineering, Osaka Prefecture University, Sakai, Osaka, 599-8531 (Japan); Duran, Alicia; Aparacio, Mario [Instituto de Cerámica y Vidrio, Consejo Superior de Investigaciones Científicas, Kelsen 5 (Campus de Cantoblanco), Madrid, 28049 (Spain)

2014-05-01

Highlights: • LiMn{sub 2}O{sub 4} thin films were prepared by using the mist CVD process. • An aqueous solution of lithium and manganese acetates is used for the precursor solution. • The cell with the LiMn{sub 2}O{sub 4} thin films exhibited a capacity of about 80 mAh/g. • The cell showed good cycling performance during 10 cycles. - Abstract: LiMn{sub 2}O{sub 4} cathode thin films for thin film lithium secondary batteries were prepared by using so-called the “mist CVD process”, employing an aqueous solution of lithium acetate and manganese acetate, as the source of Li and Mn, respectively. The aqueous solution of starting materials was ultrasonically atomized to form mist particles, and mists were transferred by nitrogen gas to silica glass substrate to form thin films. FE-SEM observation revealed that thin films obtained by this process were dense and smooth, and thin films with a thickness of about 750 nm were obtained. The electrochemical cell with the thin films obtained by sintering at 700 °C exhibited a capacity of about 80 mAh/g, and the cell showed good cycling performance during 10 cycles.

Effect of grain size on the melting point of confined thin aluminum films

Energy Technology Data Exchange (ETDEWEB)

Wejrzanowski, Tomasz; Lewandowska, Malgorzata; Sikorski, Krzysztof; Kurzydlowski, Krzysztof J. [Materials Design Division, Faculty of Materials Science and Engineering, Warsaw University of Technology, Woloska 141, 02-507 Warsaw (Poland)

2014-10-28

The melting of aluminum thin film was studied by a molecular dynamics (MD) simulation technique. The effect of the grain size and type of confinement was investigated for aluminum film with a constant thickness of 4 nm. The results show that coherent intercrystalline interface suppress the transition of solid aluminum into liquid, while free-surface gives melting point depression. The mechanism of melting of polycrystalline aluminum thin film was investigated. It was found that melting starts at grain boundaries and propagates to grain interiors. The melting point was calculated from the Lindemann index criterion, taking into account only atoms near to grain boundaries. This made it possible to extend melting point calculations to bigger grains, which require a long time (in the MD scale) to be fully molten. The results show that 4 nm thick film of aluminum melts at a temperature lower than the melting point of bulk aluminum (933 K) only when the grain size is reduced to 6 nm.

Solid-state compound phase formation of TiSi₂ thin films under stress

Directory of Open Access Journals (Sweden)

C. Theron

2010-02-01

Full Text Available Different stress situations were created on an Si(100 wafer by depositing either Si₃N₄ or SiO₂ thin films on the back side. Si₃N₄ has a different thermal expansion coefficient from that of SiO2. A thin Ti film was then deposited on the front side of the Si wafer. The structures were then annealed at various high temperatures for different periods of time. Real-time Rutherford backscattering spectrometry, as well as sample curvature measurements, were used to characterise the samples. Different reaction rates were found between Si₃N₄-deposited samples and SiO₂-deposited samples.

Combination of short-length TiO{sub 2} nanorod arrays and compact PbS quantum-dot thin films for efficient solid-state quantum-dot-sensitized solar cells

Energy Technology Data Exchange (ETDEWEB)

Zhang, Zhengguo [School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009 (China); School of Chemistry and Chemical Engineering, Beifang University of Nationalities, Yinchuan 750021 (China); Shi, Chengwu, E-mail: shicw506@foxmail.com [School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009 (China); Chen, Junjun; Xiao, Guannan; Li, Long [School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009 (China)

2017-07-15

Graphical abstract: The TiO{sub 2} nanorod array with the length of 600 nm, the diameter of 20 nm, the areal density of 500 μm{sup −2} was successfully prepared. The compact PbS quantum-dot thin film was firstly obtained on the TiO{sub 2} nanorod array by spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol. The photoelectric conversion efficiency (PCE) of the compact PbS quantum-dot thin film sensitized solar cells achieved 4.10% using spiro-OMeTAD as a hole transporting layer, while the PCE of the PbS quantum-dot sensitized solar cells was only 0.54%. - Highlights: • Preparation of TiO{sub 2} nanorod arrays with the length of 600 nm, diameter of 20 nm. • The compact PbS QD thin film and short-length TiO{sub 2} nanorod array were combined. • EDT addition improved PbS nanoparticle coverage and photovoltaic performance. • The compact PbS QD thin film sensitized solar cell achieved the PCE of 4.10%. - Abstract: Considering the balance of the hole diffusion length and the loading quantity of quantum-dots, the rutile TiO{sub 2} nanorod array with the length of 600 nm, the diameter of 20 nm, and the areal density of 500 μm{sup −2} is successfully prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 105 min. The compact PbS quantum-dot thin film on the TiO{sub 2} nanorod array is firstly obtained by the spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol (EDT). The result reveals that the strong interaction between lead and EDT is very important to control the crystallite size of PbS quantum-dots and obtain the compact PbS quantum-dot thin film on the TiO{sub 2} nanorod array. The all solid-state sensitized solar cell with the combination of the short-length, high-density TiO{sub 2} nanorod array and the compact PbS quantum-dot thin film achieves the photoelectric conversion

Fractal and multifractal analysis of LiF thin film surface

International Nuclear Information System (INIS)

Yadav, R.P.; Dwivedi, S.; Mittal, A.K.; Kumar, M.; Pandey, A.C.

2012-01-01

Highlights: ► Fractal and multifractal analysis of surface morphologies of the LiF thin films. ► Complexity and roughness of the LiF thin films increases as thickness increases. ► LiF thin films are multifractal in nature. ► Strength of the multifractality increases with thickness of the film. - Abstract: Fractal and multifractal analysis is performed on the atomic force microscopy (AFM) images of the surface morphologies of the LiF thin films of thickness 10 nm, 20 nm, and 40 nm, respectively. Autocorrelation function, height–height correlation function, and two-dimensional multifractal detrended fluctuation analysis (MFDFA) are used for characterizing the surface. It is found that the interface width, average roughness, lateral correlation length, and fractal dimension of the LiF thin film increase with the thickness of the film, whereas the roughness exponent decreases with thickness. Thus, the complexity and roughness of the LiF thin films increases as thickness increases. It is also demonstrated that the LiF thin films are multifractal in nature. Strength of the multifractality increases with thickness of the film.

Effect of the Precursor Solution Concentration of CuI Thin Film Deposited By Spin Coating Method

International Nuclear Information System (INIS)

Nur Amalina Muhmmad; Atiq, A.M.; Rusop, M.

2011-01-01

Copper (I) Iodide is a p-type semiconductor with bandgap of 3.1 eV. It is water insoluble solid with three crystalline phases α, β, γ. In this research, the effect of precursor concentration of CuI thin film deposited by spin coating method was studied. The wide band gap p type semiconductor CuI thin film was prepared by mixing the CuI powder (ALDRICH, 98 %) with 50 ml of acetonitrile as a solvent. The CuI concentration varies from 0.025 M to 0.5 M. The speed for spin coating is 1000 rpm for 60 seconds. After the deposition the CuI thin films were annealed at 150 degree Celsius. The electrical and optical properties were characterized by current-voltage (I-V) measurement using Solar Simulator (Bukoh Keiki EP-2000) and ultraviolet visible- near infrared (UV-VIS-NIR) measurement (Jasco V-670). The result shows the CuI thin film properties strongly depends on its precursor concentration. Thickness between 33.65 nm - 441.25 nm was obtained as the concentration increases. The increment of thickness affects the electrical properties which is the resistivity and conductivity of CuI thin film. For optical properties, the transmittance decreases with high concentration as high amount of CuI particle were observed in the thin films. From the transmittance, the absorption coefficient and optical band gap of CuI was determined using Taucs plot. (author)

The interfacial properties of MgCl.sub.2./sub. thin films grown on Ti(001)

Czech Academy of Sciences Publication Activity Database

Karakalos, S.; Siokou, A.; Sutara, F.; Skála, T.; Vitaliy, F.; Ladas, S.; Prince, K.; Matolin, V.; Cháb, Vladimír

2010-01-01

Roč. 133, č. 7 (2010), 074701/1-074701/11 ISSN 0021-9606 Institutional research plan: CEZ:AV0Z10100521 Keywords : silicon, * photoemission * thin films Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.920, year: 2010

SnO.sub.2./sub. and SnAcAc thin film sensors created by laser

Czech Academy of Sciences Publication Activity Database

Myslík, V.; Vysloužil, F.; Vrňata, M.; Jelínek, Miroslav; Lančok, Ján

2002-01-01

Roč. 374, - (2002), s. 285-288 ISSN 1058-725X Institutional research plan: CEZ:AV0Z1010914 Keywords : laser deposition * thin films * gas sensors Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.457, year: 2002

Preparation and characterization of vanadium oxide thin films

Energy Technology Data Exchange (ETDEWEB)

Monfort, O.; Plesch, G. [Comenius University of Bratislava, Faculty of Natural Sciences, Department of Inorganic Chemistry, 84215 Bratislava (Slovakia); Roch, T. [Comenius University of Bratislava, Faculty of Mathematics Physics and Informatics, Department of Experimental Physics, 84248 Bratislava (Slovakia)

2013-04-16

The thermotropic VO{sub 2} films have many applications, since they exhibit semiconductor-conductor switching properties at temperature around 70 grad C. Vanadium oxide thin films were prepared via sol-gel method. Spin coater was used to depose these films on Si/SiO{sub 2} and lime glass substrates. Thin films of V{sub 2}O{sub 5} can be reduced to metastable VO{sub 2} thin films at the temperature of 450 grad C under the pressure of 10{sup -2} Pa. These films are then converted to thermotropic VO{sub 2} at 700 grad C in argon under normal pressure. (authors)

Analysis of critical state response in thin films by AC susceptibility measurements

Czech Academy of Sciences Publication Activity Database

Youssef, A.; Švindrych, Z.; Hadač, J.; Janů, Zdeněk

2008-01-01

Roč. 18, č. 2 (2008), s. 1589-1592 ISSN 1051-8223 R&D Projects: GA ČR GA102/05/0942 Institutional research plan: CEZ:AV0Z10100520 Keywords : AC susceptibility * critical state * harmonics * thin film * axial magnetic-field * superconductor disks * cylinders Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.919, year: 2008

Far-infrared electrodynamics of thin superconducting NbN film in magnetic fields

Czech Academy of Sciences Publication Activity Database

Šindler, Michal; Tesař, Roman; Koláček, Jan; Szabó, P.; Samuely, P.; Hašková, V.; Kadlec, Christelle; Kadlec, Filip; Kužel, Petr

2014-01-01

Roč. 27, č. 5 (2014), 1-8 ISSN 0953-2048 R&D Projects: GA ČR(CZ) GAP204/11/0015; GA MŠk(CZ) LD14060 Institutional support: RVO:68378271 Keywords : superconductivity * thin films * scanning tunneling spectroscopy * time-domain terahertz spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.325, year: 2014

Laser nanostructuring of ZnO thin films

Energy Technology Data Exchange (ETDEWEB)

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

2016-06-30

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

LiCoO.sub.2./sub. thin-film cathodes grown by RF sputtering

Czech Academy of Sciences Publication Activity Database

Prachařová, Jarmila; Přidal, Jiří; Bludská, Jana; Jakubec, Ivo; Vorlíček, Vladimír; Málková, Zuzana; Makris, D. T.; Giorgi, R.; Jastrabík, Lubomír

2002-01-01

Roč. 108, - (2002), s. 204-212 ISSN 0378-7753 R&D Projects: GA MŠk ME 305 Institutional research plan: CEZ:AV0Z1010914 Keywords : LiCoO 3 * thin-film cathodes * Li- ion batteries Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.777, year: 2002

Restructuring in block copolymer thin films

DEFF Research Database (Denmark)

Posselt, Dorthe; Zhang, Jianqi; Smilgies, Detlef-M.

2017-01-01

Block copolymer (BCP) thin films have been proposed for a number of nanotechnology applications, such as nanolithography and as nanotemplates, nanoporous membranes and sensors. Solvent vapor annealing (SVA) has emerged as a powerful technique for manipulating and controlling the structure of BCP...... thin films, e.g., by healing defects, by altering the orientation of the microdomains and by changing the morphology. Due to high time resolution and compatibility with SVA environments, grazing-incidence small-angle X-ray scattering (GISAXS) is an indispensable technique for studying the SVA process......, providing information of the BCP thin film structure both laterally and along the film normal. Especially, state-of-the-art combined GISAXS/SVA setups at synchrotron sources have facilitated in situ and real-time studies of the SVA process with a time resolution of a few seconds, giving important insight...

Nanocoatings and ultra-thin films technologies and applications

CERN Document Server

Tiginyanu, Ion

2011-01-01

Gives a comprehensive account of the developments of nanocoatings and ultra-thin films. This book covers the fundamentals, processes of deposition and characterisation of nanocoatings, as well as the applications. It is suitable for the glass and glazing, automotive, electronics, aerospace, construction and biomedical industries in particular.$bCoatings are used for a wide range of applications, from anti-fogging coatings for glass through to corrosion control in the aerospace and automotive industries. Nanocoatings and ultra-thin films provides an up-to-date review of the fundamentals, processes of deposition, characterisation and applications of nanocoatings. Part one covers technologies used in the creation and analysis of thin films, including chapters on current and advanced coating technologies in industry, nanostructured thin films from amphiphilic molecules, chemical and physical vapour deposition methods and methods for analysing nanocoatings and ultra-thin films. Part two focuses on the applications...

Nanosphere lithography applied to magnetic thin films

Science.gov (United States)

Gleason, Russell

Magnetic nanostructures have widespread applications in many areas of physics and engineering, and nanosphere lithography has recently emerged as promising tool for the fabrication of such nanostructures. The goal of this research is to explore the magnetic properties of a thin film of ferromagnetic material deposited onto a hexagonally close-packed monolayer array of polystyrene nanospheres, and how they differ from the magnetic properties of a typical flat thin film. The first portion of this research focuses on determining the optimum conditions for depositing a monolayer of nanospheres onto chemically pretreated silicon substrates (via drop-coating) and the subsequent characterization of the deposited nanosphere layer with scanning electron microscopy. Single layers of permalloy (Ni80Fe20) are then deposited on top of the nanosphere array via DC magnetron sputtering, resulting in a thin film array of magnetic nanocaps. The coercivities of the thin films are measured using a home-built magneto-optical Kerr effect (MOKE) system in longitudinal arrangement. MOKE measurements show that for a single layer of permalloy (Py), the coercivity of a thin film deposited onto an array of nanospheres increases compared to that of a flat thin film. In addition, the coercivity increases as the nanosphere size decreases for the same deposited layer. It is postulated that magnetic exchange decoupling between neighboring nanocaps suppresses the propagation of magnetic domain walls, and this pinning of the domain walls is thought to be the primary source of the increase in coercivity.

Synthesis and characterization of nanocomposite polymer blend electrolyte thin films by spin-coating method

Energy Technology Data Exchange (ETDEWEB)

Chapi, Sharanappa; Niranjana, M.; Devendrappa, H., E-mail: dehu2010@gmail.com [Department of Physics, Mangalore University, Mangalagangothri - 574 199 (India)

2016-05-23

Solid Polymer blend electrolytes based on Polyethylene oxide (PEO) and poly vinyl pyrrolidone (PVP) complexed with zinc oxide nanoparticles (ZnO NPs; Synthesized by Co-precipitation method) thin films have prepared at a different weight percent using the spin-coating method. The complexation of the NPs with the polymer blend was confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR). The variation in film morphology was examined by polarized optical micrographs (POMs). The thermal behavior of blends was investigated under non-isothermal conditions by differential thermal analyses (DTA). A single glass transition temperature for each blend was observed, which supports the existence of compatibility of such system. The obtained results represent that the ternary based thin films are prominent materials for battery and optoelectronic device applications.

Bandtail characteristics in InN thin films

International Nuclear Information System (INIS)

Shen, W.Z.; Jiang, L.F.; Yang, H.F.; Meng, F.Y.; Ogawa, H.; Guo, Q.X.

2002-01-01

The Urbach bandtail characteristics in InN thin films grown by radio-frequency magnetron sputtering on sapphire (0001) substrates have been investigated both theoretically and experimentally. The bandtail parameter in InN thin films has been obtained by temperature-dependent transmission spectra, with the aid of a detailed calculation of the transmission profile. A bandtail model based on the calculation of density of occupied states and the carrier-phonon interaction has been employed to analyze the temperature-dependent bandtail characteristics. The bandtail parameter is in the range of 90-120 meV in the InN thin film. It is found that the carrier-phonon interaction in InN is weak and the structural disorder contribution (∼90 meV) dominates over the interactive terms. The high structural disorder in InN thin films may relate to the high nonradiative recombination centers

Epitaxial thin film growth of LiH using a liquid-Li atomic template

Energy Technology Data Exchange (ETDEWEB)

Oguchi, Hiroyuki, E-mail: oguchi@nanosys.mech.tohoku.ac.jp [Department of Nanomechanics, Tohoku University, Sendai 980-8579 (Japan); Micro System Integration Center (muSIC), Tohoku University, Sendai 980-0845 (Japan); Ikeshoji, Tamio; Orimo, Shin-ichi [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Advanced Institute for Materials Research (AIMR), Tohoku University, Sendai 980-8577 (Japan); Ohsawa, Takeo; Shiraki, Susumu; Hitosugi, Taro [Advanced Institute for Materials Research (AIMR), Tohoku University, Sendai 980-8577 (Japan); Kuwano, Hiroki [Department of Nanomechanics, Tohoku University, Sendai 980-8579 (Japan)

2014-11-24

We report on the synthesis of lithium hydride (LiH) epitaxial thin films through the hydrogenation of a Li melt, forming abrupt LiH/MgO interface. Experimental and first-principles molecular dynamics studies reveal a comprehensive microscopic picture of the crystallization processes, which sheds light on the fundamental atomistic growth processes that have remained unknown in the vapor-liquid-solid method. We found that the periodic structure that formed, because of the liquid-Li atoms at the film/MgO-substrate interface, serves as an atomic template for the epitaxial growth of LiH crystals. In contrast, films grown on the Al{sub 2}O{sub 3} substrates indicated polycrystalline films with a LiAlO{sub 2} secondary phase. These results and the proposed growth process provide insights into the preparation of other alkaline metal hydride thin films on oxides. Further, our investigations open the way to explore fundamental physics and chemistry of metal hydrides including possible phenomena that emerge at the heterointerfaces of metal hydrides.

Atomic Layer Deposited Thin Films for Dielectrics, Semiconductor Passivation, and Solid Oxide Fuel Cells

Science.gov (United States)

Xu, Runshen

, ultra-thin layer of encapsulating ZnS is coated on the surface of GaSb and GaSb/InAs substrates. The 2 nm-thick ZnS film is found to provide a long-term protection against reoxidation for one order and a half longer times than prior reported passivation likely due to its amorphous structure without pinholes. Finally, a combination of binary ALD processes is developed and demonstrated for the growth of yttria-stabilized zirconia films using alkylamido-cyclopentadiengyls zirconium and tris(isopropyl-cyclopentadienyl)yttrium, as zirconium and yttrium precursors, respectively, with ozone being the oxidant. The desired cubic structure of YSZ films is apparently achieved after post-deposition annealing. Further, platinum is atomic layer deposited as electrode on YSZ (8 mol% of Yttria) within the same system. In order to control the morphology of as-deposited Pt thin structure, the nucleation behavior of Pt on amorphous and cubic YSZ is investigated. Three different morphologies of Pt are observed, including nanoparticle, porous and dense films, which are found to depend on the ALD cycle number and the structure and morphology of they underlying ALD YSZ films.

Hybrid Perovskite Thin-Film Photovoltaics: In Situ Diagnostics and Importance of the Precursor Solvate Phases

KAUST Repository

Munir, Rahim

2016-11-07

Solution-processed hybrid perovskite semiconductors attract a great deal of attention, but little is known about their formation process. The one-step spin-coating process of perovskites is investigated in situ, revealing that thin-film formation is mediated by solid-state precursor solvates and their nature. The stability of these intermediate phases directly impacts the quality and reproducibility of thermally converted perovskite films and their photovoltaic performance.

Hybrid Perovskite Thin-Film Photovoltaics: In Situ Diagnostics and Importance of the Precursor Solvate Phases

KAUST Repository

Munir, Rahim; Sheikh, Arif D.; Abdelsamie, Maged; Hu, Hanlin; Yu, Liyang; Zhao, Kui; Kim, Taesoo; El Tall, Omar; Li, Ruipeng; Smilgies, Detlef M.; Amassian, Aram

2016-01-01

Solution-processed hybrid perovskite semiconductors attract a great deal of attention, but little is known about their formation process. The one-step spin-coating process of perovskites is investigated in situ, revealing that thin-film formation is mediated by solid-state precursor solvates and their nature. The stability of these intermediate phases directly impacts the quality and reproducibility of thermally converted perovskite films and their photovoltaic performance.

Thin films of mixed metal compounds

Science.gov (United States)

Mickelsen, Reid A.; Chen, Wen S.

1985-01-01

A compositionally uniform thin film of a mixed metal compound is formed by simultaneously evaporating a first metal compound and a second metal compound from independent sources. The mean free path between the vapor particles is reduced by a gas and the mixed vapors are deposited uniformly. The invention finds particular utility in forming thin film heterojunction solar cells.

Thin-Film Power Transformers

Science.gov (United States)

Katti, Romney R.

1995-01-01

Transformer core made of thin layers of insulating material interspersed with thin layers of ferromagnetic material. Flux-linking conductors made of thinner nonferromagnetic-conductor/insulator multilayers wrapped around core. Transformers have geometric features finer than those of transformers made in customary way by machining and mechanical pressing. In addition, some thin-film materials exhibit magnetic-flux-carrying capabilities superior to those of customary bulk transformer materials. Suitable for low-cost, high-yield mass production.

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.

Magnetic damping phenomena in ferromagnetic thin-films and multilayers

Science.gov (United States)

Azzawi, S.; Hindmarch, A. T.; Atkinson, D.

2017-11-01

Damped ferromagnetic precession is an important mechanism underpinning the magnetisation processes in ferromagnetic materials. In thin-film ferromagnets and ferromagnetic/non-magnetic multilayers, the role of precession and damping can be critical for spintronic device functionality and as a consequence there has been significant research activity. This paper presents a review of damping in ferromagnetic thin-films and multilayers and collates the results of many experimental studies to present a coherent synthesis of the field. The terms that are used to define damping are discussed with the aim of providing consistent definitions for damping phenomena. A description of the theoretical basis of damping is presented from early developments to the latest discussions of damping in ferromagnetic thin-films and multilayers. An overview of the time and frequency domain methods used to study precessional magnetisation behaviour and damping in thin-films and multilayers is also presented. Finally, a review of the experimental observations of magnetic damping in ferromagnetic thin-films and multilayers is presented with the most recent explanations. This brings together the results from many studies and includes the effects of ferromagnetic film thickness, the effects of composition on damping in thin-film ferromagnetic alloys, the influence of non-magnetic dopants in ferromagnetic films and the effects of combining thin-film ferromagnets with various non-magnetic layers in multilayered configurations.

The investigation of solid solutions thin interlayers in CdS/CdTe film heterosystems

International Nuclear Information System (INIS)

Khrypunov, G.; Boyko, B.; Chernykh, O.

1999-01-01

The photo-response spectral dependence of ITO/CdTe/Au/Cu and ITO/CdS/CdTe/Au/Cu film heterosystems were investigated. At illuminations ITO/CdS/CdTe/Au/Cu heterosystems on ITO side a photo-response maximum was observed for photon absorption with a wavelength of 0.87 μm that is stipulated by formation of CdS x Te 1-x solid solutions interlayer with band gap width less than in CdTe layer. By use optical measurement transmittance spectra was selected a spectral photosensitivity interval appropriate to the contribution of non-equilibrium charge carriers generated in solid solutions interlayer by photon absorption with energy less than CdTe film band gap

Chemical vapour deposition of thin-film dielectrics

International Nuclear Information System (INIS)

Vasilev, Vladislav Yu; Repinsky, Sergei M

2005-01-01

Data on the chemical vapour deposition of thin-film dielectrics based on silicon nitride, silicon oxynitride and silicon dioxide and on phosphorus- and boron-containing silicate glasses are generalised. The equipment and layer deposition procedures are described. Attention is focussed on the analysis and discussion of the deposition kinetics and on the kinetic models for film growth. The film growth processes are characterised and data on the key physicochemical properties of thin-film covalent dielectric materials are given.

Residual stress in spin-cast polyurethane thin films

Energy Technology Data Exchange (ETDEWEB)

Zhang, Hong; Zhang, Li, E-mail: lizhang@mae.cuhk.edu.hk [Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin N.T., Hong Kong (China); Chow Yuk Ho Technology Centre for Innovative Medicine, The Chinese University of Hong Kong, Shatin N.T., Hong Kong (China)

2015-01-19

Residual stress is inevitable during spin-casting. Herein, we report a straightforward method to evaluate the residual stress in as-cast polyurethane thin films using area shrinkage measurement of films in floating state, which shows that the residual stress is independent of radial location on the substrate and decreased with decreasing film thickness below a critical value. We demonstrate that the residual stress is developed due to the solvent evaporation after vitrification during spin-casting and the polymer chains in thin films may undergo vitrification at an increased concentration. The buildup of residual stress in spin-cast polymer films provides an insight into the size effects on the nature of polymer thin films.

Room temperature inorganic polycondensation of oxide (Cu2O and ZnO) nanoparticles and thin films preparation by the dip-coating technique

International Nuclear Information System (INIS)

Salek, G.; Tenailleau, C.; Dufour, P.; Guillemet-Fritsch, S.

2015-01-01

Oxide thin solid films were prepared by dip-coating into colloidal dispersions of oxide nanoparticles stabilized at room temperature without the use of chelating or complex organic dispersing agents. Crystalline oxide nanoparticles were obtained by inorganic polycondensation and characterized by X-ray diffraction and field emission gun scanning electron microscopy. Water and ethanol synthesis and solution stabilization of oxide nanoparticle method was optimized to prepare two different structural and compositional materials, namely Cu 2 O and ZnO. The influence of hydrodynamic parameters over the particle shape and size is discussed. Spherical and rod shape nanoparticles were formed for Cu 2 O and ZnO, respectively. Isoelectric point values of 7.5 and 8.2 were determined for cuprous and zinc oxides, respectively, after zeta potential measurements. A shear thinning and thixotropic behavior was observed in both colloidal sols after peptization at pH ~ 6 with dilute nitric acid. Every colloidal dispersion stabilized in a low cost and environmentally friendly azeotrope solution composed of 96 vol.% of ethanol with water was used for the thin film preparation by the dip-coating technique. Optical properties of the light absorber cuprous oxide and transparent zinc oxide thin solid films were characterized by means of transmittance and reflectance measurements (300–1100 nm). - Highlights: • Room temperature inorganic polycondensation of crystalline oxides • Water and ethanol synthesis and solution stabilization of oxide nanoparticles • Low cost method for thin solid film preparation

Simulated Thin-Film Growth and Imaging

Science.gov (United States)

Schillaci, Michael

2001-06-01

Thin-films have become the cornerstone of the electronics, telecommunications, and broadband markets. A list of potential products includes: computer boards and chips, satellites, cell phones, fuel cells, superconductors, flat panel displays, optical waveguides, building and automotive windows, food and beverage plastic containers, metal foils, pipe plating, vision ware, manufacturing equipment and turbine engines. For all of these reasons a basic understanding of the physical processes involved in both growing and imaging thin-films can provide a wonderful research project for advanced undergraduate and first-year graduate students. After producing rudimentary two- and three-dimensional thin-film models incorporating ballsitic deposition and nearest neighbor Coulomb-type interactions, the QM tunneling equations are used to produce simulated scanning tunneling microscope (SSTM) images of the films. A discussion of computational platforms, languages, and software packages that may be used to accomplish similar results is also given.

Nanostructured thin films as functional coatings

Energy Technology Data Exchange (ETDEWEB)

Lazar, Manoj A; Tadvani, Jalil K; Tung, Wing Sze; Lopez, Lorena; Daoud, Walid A, E-mail: Walid.Daoud@sci.monash.edu.au [School of Applied Sciences and Engineering, Monash University, Churchill, VIC 3842 (Australia)

2010-06-15

Nanostructured thin films is one of the highly exploiting research areas particularly in applications such as photovoltaics, photocatalysis and sensor technologies. Highly tuned thin films, in terms of thickness, crystallinity, porosity and optical properties, can be fabricated on different substrates using the sol-gel method, chemical solution deposition (CSD), electrochemical etching, along with other conventional methods such as chemical vapour deposition (CVD) and physical vapour deposition (PVD). The above mentioned properties of these films are usually characterised using surface analysis techniques such as XRD, SEM, TEM, AFM, ellipsometry, electrochemistry, SAXS, reflectance spectroscopy, STM, XPS, SIMS, ESCA, X-ray topography and DOSY-NMR. This article presents a short review of the preparation and characterisation of thin films of nanocrystalline titanium dioxide and modified silicon as well as their application in solar cells, water treatment, water splitting, self cleaning fabrics, sensors, optoelectronic devices and lab on chip systems.

Thin film characterization by resonantly excited internal standing waves

Energy Technology Data Exchange (ETDEWEB)

Di Fonzio, S [SINCROTRONE TRIESTE, Trieste (Italy)

1996-09-01

This contribution describes how a standing wave excited in a thin film can be used for the characterization of the properties of the film. By means of grazing incidence X-ray reflectometry one can deduce the total film thickness. On the other hand in making use of a strong resonance effect in the electric field intensity distribution inside a thin film on a bulk substrate one can learn more about the internal structure of the film. The profile of the internal standing wave is proven by diffraction experiments. The most appropriate non-destructive technique for the subsequent thin film characterization is angularly dependent X-ray fluorescence analysis. The existence of the resonance makes it a powerful tool for the detection of impurities and of ultra-thin maker layers, for which the position can be determined with very high precision (about 1% of the total film thickness). This latter aspect will be discussed here on samples which had a thin Ti marker layer at different positions in a carbon film. Due to the resonance enhancement it was still possible to perform these experiments with a standard laboratory x-ray tube and with standard laboratory tool for marker or impurity detection in thin films.

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.

Photoluminescence of electron beam evaporated CaS:Bi thin films

CERN Document Server

Smet, P F; Poelman, D R; Meirhaeghe, R L V

2003-01-01

For the first time, the photoluminescence (PL) of electron beam evaporated CaS:Bi thin films is reported. Luminescent CaS:Bi powder prepared out of aqueous solutions was used as source material. The influence of substrate temperature on the PL and the morphology of thin films is discussed, and an optimum is determined. Substrate temperatures between 200 deg. C and 300 deg. C lead to good quality thin films with sufficient PL intensity. As-deposited thin films show two emission bands, peaking at 450 and 530 nm. Upon annealing the emission intensity increases, and annealing at 800 deg. C is sufficient to obtain a homogeneously blue emitting thin film (CIE colour coordinates (0.17; 0.12)), thanks to a single remaining emission band at 450 nm. The influence of ambient temperature on the PL of CaS:Bi powder and thin films was also investigated and it was found that CaS:Bi thin films show a favourable thermal quenching behaviour near room temperature.

Excimer Laser Deposition of PLZT Thin Films

National Research Council Canada - National Science Library

Petersen, GAry

1991-01-01

.... In order to integrate these devices into optical systems, the production of high quality thin films with high transparency and perovskite crystal structure is desired. This requires development of deposition technologies to overcome the challenges of depositing and processing PLZT thin films.

Carrier transport in polycrystalline silicon thin films solar cells grown on a highly textured structure

Czech Academy of Sciences Publication Activity Database

Honda, Shinya; Takakura, H.; Hamakawa, Y.; Muhida, R.; Kawamura, T.; Harano, T.; Toyama, T.; Okamoto, H.

2004-01-01

Roč. 43, 9A (2004), s. 5955-5959 ISSN 0021-4922 Institutional research plan: CEZ:AV0Z1010914 Keywords : polycrystalline silicon thin film * solar cells * substrate texture Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.142, year: 2004

Pyroelectricity of silicon-doped hafnium oxide thin films

Science.gov (United States)

Jachalke, Sven; Schenk, Tony; Park, Min Hyuk; Schroeder, Uwe; Mikolajick, Thomas; Stöcker, Hartmut; Mehner, Erik; Meyer, Dirk C.

2018-04-01

Ferroelectricity in hafnium oxide thin films is known to be induced by various doping elements and in solid-solution with zirconia. While a wealth of studies is focused on their basic ferroelectric properties and memory applications, thorough studies of the related pyroelectric properties and their application potential are only rarely found. This work investigates the impact of Si doping on the phase composition and ferro- as well as pyroelectric properties of thin film capacitors. Dynamic hysteresis measurements and the field-free Sharp-Garn method were used to correlate the reported orthorhombic phase fractions with the remanent polarization and pyroelectric coefficient. Maximum values of 8.21 µC cm-2 and -46.2 µC K-1 m-2 for remanent polarization and pyroelectric coefficient were found for a Si content of 2.0 at%, respectively. Moreover, temperature-dependent measurements reveal nearly constant values for the pyroelectric coefficient and remanent polarization over the temperature range of 0 ° C to 170 ° C , which make the material a promising candidate for IR sensor and energy conversion applications beyond the commonly discussed use in memory applications.

Electron Microscopy Characterization of Vanadium Dioxide Thin Films and Nanoparticles

Science.gov (United States)

Rivera, Felipe

Vanadium dioxide (VO_2) is a material of particular interest due to its exhibited metal to insulator phase transition at 68°C that is accompanied by an abrupt and significant change in its electronic and optical properties. Since this material can exhibit a reversible drop in resistivity of up to five orders of magnitude and a reversible drop in infrared optical transmission of up to 80%, this material holds promise in several technological applications. Solid phase crystallization of VO_2 thin films was obtained by a post-deposition annealing process of a VO_{x,x approx 2} amorphous film sputtered on an amorphous silicon dioxide (SiO_2) layer. Scanning electron microscopy (SEM) and electron-backscattered diffraction (EBSD) were utilized to study the morphology of the solid phase crystallization that resulted from this post-deposition annealing process. The annealing parameters ranged in temperature from 300°C up to 1000°C and in time from 5 minutes up to 12 hours. Depending on the annealing parameters, EBSD showed that this process yielded polycrystalline vanadium dioxide thin films, semi-continuous thin films, and films of isolated single-crystal particles. In addition to these films on SiO_2, other VO_2 thin films were deposited onto a-, c-, and r-cuts of sapphire and on TiO_2(001) heated single-crystal substrates by pulsed-laser deposition (PLD). The temperature of the substrates was kept at ˜500°C during deposition. EBSD maps and orientation imaging microscopy were used to study the epitaxy and orientation of the VO_2 grains deposited on the single crystal substrates, as well as on the amorphous SiO_2 layer. The EBSD/OIM results showed that: 1) For all the sapphire substrates analyzed, there is a predominant family of crystallographic relationships wherein the rutile VO_2{001} planes tend to lie parallel to the sapphire's {10-10} and the rutile VO_2{100} planes lie parallel to the sapphire's {1-210} and {0001}. Furthermore, while this family of

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

Characterization of ultrasonic spray pyrolysed ruthenium oxide thin films

Energy Technology Data Exchange (ETDEWEB)

Patil, P.S.; Ennaoui, E.A.; Lokhande, C.D.; Mueller, M.; Giersig, M.; Diesner, K.; Tributsch, H. [Hahn-Meitner-Institut Berlin GmbH (Germany). Bereich Physikalische Chemie

1997-11-21

The ultrasonic spray pyrolysis (USP) technique was employed to deposit ruthenium oxide thin films. The films were prepared at 190 C substrate temperature and further annealed at 350 C for 30 min in air. The films were 0.22 {mu} thick and black grey in color. The structural, compositional and optical properties of ruthenium oxide thin films are reported. Contactless transient photoconductivity measurement was carried out to calculate the decay time of excess charge carriers in ruthenium oxide thin films. (orig.) 28 refs.

Field ion microscope studies on thin films

International Nuclear Information System (INIS)

Cavaleru, A.; Scortaru, A.

1976-01-01

A review of the progress made in the last years in FIM application to thin film structure studies and adatom properties important in the nucleation stage of thin film growth: substrate binding and mobility of individual adatoms, behaviour of adatoms clusters is presented. (author)

Fabrication of Crack-Free Barium Titanate Thin Film with High Dielectric Constant Using Sub-Micrometric Scale Layer-by-Layer E-Jet Deposition

Directory of Open Access Journals (Sweden)

Junsheng Liang

2016-01-01

Full Text Available Dense and crack-free barium titanate (BaTiO3, BTO thin films with a thickness of less than 4 μm were prepared by using sub-micrometric scale, layer-by-layer electrohydrodynamic jet (E-jet deposition of the suspension ink which is composed of BTO nanopowder and BTO sol. Impacts of the jet height and line-to-line pitch of the deposition on the micro-structure of BTO thin films were investigated. Results show that crack-free BTO thin films can be prepared with 4 mm jet height and 300 μm line-to-line pitch in this work. Dielectric constant of the prepared BTO thin film was recorded as high as 2940 at 1 kHz at room temperature. Meanwhile, low dissipation factor of the BTO thin film of about 8.6% at 1 kHz was also obtained. The layer-by-layer E-jet deposition technique developed in this work has been proved to be a cost-effective, flexible and easy to control approach for the preparation of high-quality solid thin film.

Magnetic surfaces, thin films, and multilayers

International Nuclear Information System (INIS)

Parkin, S.S.P.; Renard, J.P.; Shinjo, T.; Zinn, W.

1992-01-01

This paper details recent developments in the magnetism of surfaces, thin films and multilayers. More than 20 invited contributions and more than 60 contributed papers attest to the great interest and vitality of this subject. In recent years the study of magnetic surfaces, thin films and multilayers has undergone a renaissance, partly motivated by the development of new growth and characterization techniques, but perhaps more so by the discovery of many exciting new properties, some quite unanticipated. These include, most recently, the discovery of enormous values of magnetoresistance in magnetic multilayers far exceeding those found in magnetic single layer films and the discovery of oscillatory interlayer coupling in transition metal multilayers. These experimental studies have motivated much theoretical work. However these developments are to a large extent powered by materials engineering and our ability to control and understand the growth of thin layers just a few atoms thick. The preparation of single crystal thin film layers and multilayers remains important for many studies, in particular, for properties dependent. These studies obviously require engineering not just a layer thicknesses but of lateral dimensions as well. The properties of such structures are already proving to be a great interest

Thin films prepared from tungstate glass matrix

Energy Technology Data Exchange (ETDEWEB)

Montanari, B.; Ribeiro, S.J.L.; Messaddeq, Y. [Departamento de Quimica Geral e Inorganica, Instituto de Quimica, Sao Paulo State University-UNESP, CP 355, CEP 14800-900, Araraquara, SP (Brazil); Li, M.S. [Instituto de Fisica, USP, CP 369, CEP 13560-970, Sao Carlos, SP (Brazil); Poirier, G. [Departamento de Ciencias Exatas, UNIFAL-MG, CEP 37130-000, Alfenas-MG (Brazil)], E-mail: gael@unifal-mg.edu.br

2008-01-30

Vitreous samples containing high concentrations of WO{sub 3} (above 40% M) have been used as a target to prepare thin films. Such films were deposited using the electron beam evaporation method onto soda-lime glass substrates. These films were characterized by X-ray diffraction (XRD), perfilometry, X-ray energy dispersion spectroscopy (EDS), M-Lines and UV-vis absorption spectroscopy. In this work, experimental parameters were established to obtain stable thin films showing a chemical composition close to the glass precursor composition and with a high concentration of WO{sub 3}. These amorphous thin films of about 4 {mu}m in thickness exhibit a deep blue coloration but they can be bleached by thermal treatment near the glass transition temperature. Such bleached films show several guided modes in the visible region and have a high refractive index. Controlled crystallization was realized and thus it was possible to obtain WO{sub 3} microcrystals in the amorphous phase.

Characterization of Sucrose Thin Films for Biomedical Applications

Directory of Open Access Journals (Sweden)

S. L. Iconaru

2011-01-01

Full Text Available Sucrose is a natural osmolyte accumulated in the cells of organisms as they adapt to environmental stress. In vitro sucrose increases protein stability and forces partially unfolded structures to refold. Thin films of sucrose (C12H22O11 were deposited on thin cut glass substrates by the thermal evaporation technique (P∼10−5 torr. Characteristics of thin films were put into evidence by Fourier Transform Infrared Spectroscopy (FTIR, X-ray Photoelectron Spectroscopy (XPS, scanning electron microscopy (SEM, and differential thermal analysis and thermal gravimetric analysis (TG/DTA. The experimental results confirm a uniform deposition of an adherent layer. In this paper we present a part of the characteristics of sucrose thin films deposited on glass in medium vacuum conditions, as a part of a culture medium for osteoblast cells. Osteoblast cells were used to determine proliferation, viability, and cytotoxicity interactions with sucrose powder and sucrose thin films. The osteoblast cells have been provided from the American Type Culture Collection (ATCC Centre. The outcome of this study demonstrated the effectiveness of sucrose thin films as a possible nontoxic agent for biomedical applications.

Significant questions in thin liquid film heat transfer

International Nuclear Information System (INIS)

Bankoff, S.G.

1994-01-01

Thin liquid films appear in many contexts, such as the cooling of gas turbine blade tips, rocket engines, microelectronics arrays, and hot fuel element surfaces in hypothetical nuclear reactor accidents. Apart from these direct cooling applications of thin liquid layers, thin films form a crucial element in determining the allowable heat flux limits in boiling. This is because the last stages of dryout almost invariably involve the rupture of a residual liquid film, either as a microlayer underneath the bubbles, or a thin annular layer in a high-quality burnout scenario. The destabilization of these thin films under the combined actions of shear stress, evaporation, and thermocapillary effects is quite complex. The later stages of actual rupture to form dry regions, which then expand, resulting in possible overheating, are even more complex and less well understood. However, significant progress has been made in understanding the behavior of these thin films, which are subject to competing instabilities prior to actual rupture. This will be reviewed briefly. Recent work on the advance, or recession, of contact lines will also be described briefly, and significant questions that still remain to be answered will be discussed. 68 refs., 7 figs

Novel photon management for thin-film photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Menon, Rajesh [Univ. of Utah, Salt Lake City, UT (United States)

2016-11-11

The objective of this project is to enable commercially viable thin-film photovoltaics whose efficiencies are increased by over 10% using a novel optical spectral-separation technique. A thin planar diffractive optic is proposed that efficiently separates the solar spectrum and assigns these bands to optimal thin-film sub-cells. An integrated device that is comprised of the optical element, an array of sub-cells and associated packaging is proposed.

Flexible solid-state supercapacitors based on three-dimensional graphene hydrogel films.

Science.gov (United States)

Xu, Yuxi; Lin, Zhaoyang; Huang, Xiaoqing; Liu, Yuan; Huang, Yu; Duan, Xiangfeng

2013-05-28

Flexible solid-state supercapacitors are of considerable interest as mobile power supply for future flexible electronics. Graphene or carbon nanotubes based thin films have been used to fabricate flexible solid-state supercapacitors with high gravimetric specific capacitances (80-200 F/g), but usually with a rather low overall or areal specific capacitance (3-50 mF/cm(2)) due to the ultrasmall electrode thickness (typically a few micrometers) and ultralow mass loading, which is not desirable for practical applications. Here we report the exploration of a three-dimensional (3D) graphene hydrogel for the fabrication of high-performance solid-state flexible supercapacitors. With a highly interconnected 3D network structure, graphene hydrogel exhibits exceptional electrical conductivity and mechanical robustness to make it an excellent material for flexible energy storage devices. Our studies demonstrate that flexible supercapacitors with a 120 μm thick graphene hydrogel thin film can exhibit excellent capacitive characteristics, including a high gravimetric specific capacitance of 186 F/g (up to 196 F/g for a 42 μm thick electrode), an unprecedented areal specific capacitance of 372 mF/cm(2) (up to 402 mF/cm(2) for a 185 μm thick electrode), low leakage current (10.6 μA), excellent cycling stability, and extraordinary mechanical flexibility. This study demonstrates the exciting potential of 3D graphene macrostructures for high-performance flexible energy storage devices.

Thin films as an emerging platform for drug delivery

Directory of Open Access Journals (Sweden)

Sandeep Karki

2016-10-01

Full Text Available Pharmaceutical scientists throughout the world are trying to explore thin films as a novel drug delivery tool. Thin films have been identified as an alternative approach to conventional dosage forms. The thin films are considered to be convenient to swallow, self-administrable, and fast dissolving dosage form, all of which make it as a versatile platform for drug delivery. This delivery system has been used for both systemic and local action via several routes such as oral, buccal, sublingual, ocular, and transdermal routes. The design of efficient thin films requires a comprehensive knowledge of the pharmacological and pharmaceutical properties of drugs and polymers along with an appropriate selection of manufacturing processes. Therefore, the aim of this review is to provide an overview of the critical factors affecting the formulation of thin films, including the physico-chemical properties of polymers and drugs, anatomical and physiological constraints, as well as the characterization methods and quality specifications to circumvent the difficulties associated with formulation design. It also highlights the recent trends and perspectives to develop thin film products by various companies.

Optical NIR-VIS-VUV constants of advanced substrates for thin-film devices

Czech Academy of Sciences Publication Activity Database

Chernova, Ekaterina; Brooks, Christopher D.; Chvostová, Dagmar; Bryknar, Z.; Dejneka, Alexandr; Tyunina, Marina

2017-01-01

Roč. 7, č. 11 (2017), s. 3844-3862 ISSN 2159-3930 R&D Projects: GA ČR GA15-13778S; GA MŠk EF15_008/0000162; GA ČR GA15-15123S Grant - others:ELI Beamlines(XE) CZ.02.1.01/0.0/0.0/15_008/0000162 Institutional support: RVO:68378271 Keywords : ellipsometry * epitaxy * optical properties * single-crystal substrates * thin films Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 2.591, year: 2016

Liquid flow deposited spinel (Ni,Mn){sub 3}O{sub 4} thin films for microbolometer applications

Energy Technology Data Exchange (ETDEWEB)

Le, Duc Thang, E-mail: ducthang36@skku.edu [Intelligent Electronic Component Team, Electronic Materials Convergence Division, Korea Institute of Ceramic Engineering and Technology, Seoul 153-801 (Korea, Republic of); School of Advanced Materials Science & Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Jeon, Chang Jun; Lee, Kui Woong; Jeong, Young Hun; Yun, Ji Sun [Intelligent Electronic Component Team, Electronic Materials Convergence Division, Korea Institute of Ceramic Engineering and Technology, Seoul 153-801 (Korea, Republic of); Yoon, Dae Ho, E-mail: dhyoon@skku.edu [School of Advanced Materials Science & Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Cho, Jeong Ho, E-mail: goedc@kicet.re.kr [Intelligent Electronic Component Team, Electronic Materials Convergence Division, Korea Institute of Ceramic Engineering and Technology, Seoul 153-801 (Korea, Republic of)

2015-03-01

Highlights: • Highly quality (Ni,Mn){sub 3}O{sub 4} thin films were grown using liquid flow deposited (LFD) technique. • It is possible to deposit multi–component manganite–oxide thin films by LFD at low temperatures. • Nickel–manganite films showed a good negative temperature coefficient (NTC) characteristic. • Liquid flow deposited (Ni,Mn){sub 3}O{sub 4} thin films are very potential for microbolometer applications. - Abstract: A liquid flow deposition (LFD) technique was initially used for the fabrication of single-component Mn{sub 3}O{sub 4} thin films onto Si wafer substrates at a range of substrate temperatures of 30–80 °C, with the introduction of an oxidizing reagent (H{sub 2}O{sub 2}). As a result, solid thin films were well formed from an aqueous solution. An X-ray diffraction (XRD) analysis showed typical characteristics of hausmannite Mn{sub 3}O{sub 4} with a spinel tetragonal phase. Field-emission scanning electron microscopy (FE-SEM) observations revealed nano-sized grains arranged uniformly on a dense and smooth surface for all of the as-deposited films. On the other hand, the LFD method was then extended to prepare two-component nickel–manganite films according to the binary chemical composition of Ni{sub x}Mn{sub 3−x}O{sub 4} with x = 0.02–0.2. The as-grown nickel–manganite films showed a surface with a good quality with a spherical bead-like architecture when x ≤ 0.10, while a conversion from spherical grains into highly porous nanowalls in the microstructure was noted in films when x ≥ 0.12. These results signify that it is possible to fabricate various multi-component manganite-oxide thin films at a low temperature. In addition, the dependences of the room-temperature electrical resistivity (ρ) and the temperature coefficient of resistance (TCR) on the Ni substitution level (x) were investigated on films annealed at 400 °C.

A liquid-like model for the morphology evolution of ion bombarded thin films

Energy Technology Data Exchange (ETDEWEB)

Repetto, L., E-mail: luca.repetto@unige.it [Department of Physics and Nanomed Labs, Università di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Lo Savio, R. [Department of Physics and Nanomed Labs, Università di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Šetina Batič, B. [Inštitut Za Kovinske Materiale in Tehnologije, Lepi pot 11, 1000 Ljubljana (Slovenia); Firpo, G.; Angeli, E.; Valbusa, U. [Department of Physics and Nanomed Labs, Università di Genova, Via Dodecaneso 33, 16146 Genova (Italy)

2015-07-01

Thin solid films exposed to ion irradiation exhibit a peculiar evolution that can differ substantially from what is observed for bulk samples. The phenomenology of the patterns that self-organize on the substrate is very rich, with morphologies that display several degrees of order upon the modification of initial film characteristics and irradiation parameters. This richness paves the way for the fabrication of novel functional surfaces, but it is also an indication of the complexity of the underlying driving mechanisms. A remarkable simplification for the comprehension of these phenomena can come from the noteworthy similarity of the obtained patterns with those showing up when liquids dewet from their substrates. Here, we analyze the possibility to apply a liquid-like model to explain the morphology evolution of ion bombarded thin films for the whole phenomenology showing up in experiments. In establishing this connection between liquids and ion bombarded thin films, we propose to use also for liquids the insight gained for our system with recent experiments that stress the importance of the substrate topography for the selection of the dewetting mechanism. If confirmed, this result would lead to a reconsideration of the importance of capillary waves in spinodal dewetting, and will help to understand the low reproducibility of the related experimental results.

Formation and structure of V-Zr amorphous alloy thin films

KAUST Repository

King, Daniel J M

2015-01-01

Although the equilibrium phase diagram predicts that alloys in the central part of the V-Zr system should consist of V2Zr Laves phase with partial segregation of one element, it is known that under non-equilibrium conditions these materials can form amorphous structures. Here we examine the structures and stabilities of thin film V-Zr alloys deposited at room temperature by magnetron sputtering. The films were characterized by X-ray diffraction, transmission electron microscopy and computational methods. Atomic-scale modelling was used to investigate the enthalpies of formation of the various competing structures. The calculations confirmed that an amorphous solid solution would be significantly more stable than a random body-centred solid solution of the elements, in agreement with the experimental results. In addition, the modelling effort provided insight into the probable atomic configurations of the amorphous structures allowing predictions of the average distance to the first and second nearest neighbours in the system.

Investigations of Si Thin Films as Anode of Lithium-Ion Batteries

Energy Technology Data Exchange (ETDEWEB)

Wu, Qingliu [Department of Chemical; Shi, Bing; Bareño, Javier; Liu, Yuzi; Maroni, Victor A.; Zhai, Dengyun; Dees, Dennis W.; Lu, Wenquan

2018-01-22

Amorphous silicon thin films having various thicknesses were investigated as a negative electrode material for lithium-ion batteries. Electrochemical characterization of the 20 nm thick thin silicon film revealed a very low first cycle Coulombic efficiency, which can be attributed to the silicon oxide layer formed on both the surface of the as-deposited Si thin film and the interface between the Si and the substrate. Among the investigated films, the 100 nm Si thin film demonstrated the best performance in terms of first cycle efficiency and cycle life. Observations from scanning electron microscopy demonstrated that the generation of cracks was inevitable in the cycled Si thin films, even as the thickness of the film was as little as 20 nm, which was not predicted by previous modeling work. However, the cycling performance of the 20 and 100 nm silicon thin films was not detrimentally affected by these cracks. The poor capacity retention of the 1 mu m silicon thin film was attributed to the delamination.

Annealing-induced recovery of indents in thin Au(Fe bilayer films

Directory of Open Access Journals (Sweden)

Anna Kosinova

2016-12-01

Full Text Available We employed depth-sensing nanoindentation to produce ordered arrays of indents on the surface of 50 nm-thick Au(Fe films deposited on sapphire substrates. The maximum depth of the indents was approximately one-half of the film thickness. The indented films were annealed at a temperature of 700 °C in a forming gas atmosphere. While the onset of solid-state dewetting was observed in the unperturbed regions of the film, no holes to the substrate were observed in the indented regions. Instead, the film annealing resulted in the formation of hillocks at the indent locations, followed by their dissipation and the formation of shallow depressions nearby after subsequent annealing treatments. This annealing-induced evolution of nanoindents was interpreted in terms of annihilation of dislocation loops generated during indentation, accompanied by the formation of nanopores at the grain boundaries and their subsequent dissolution. The application of the processes uncovered in this work show great potential for the patterning of thin films.

Faraday effect of polycrystalline bismuth iron garnet thin film prepared by mist chemical vapor deposition method

International Nuclear Information System (INIS)

Yao, Situ; Kamakura, Ryosuke; Murai, Shunsuke; Fujita, Koji; Tanaka, Katsuhisa

2017-01-01

We have synthesized polycrystalline thin film composed of a single phase of metastable bismuth iron garnet, Bi_3Fe_5O_1_2, on a fused silica substrate, one of the most widely utilized substrates in the solid-state electronics, by using mist chemical vapor deposition (mist CVD) method. The phase purity and stoichiometry are confirmed by X-ray diffraction and Rutherford backscattering spectrometry. The resultant thin film shows a small surface roughness of 3.251 nm. The saturation magnetization at room temperature is 1200 G, and the Faraday rotation angle at 633 nm reaches −5.2 deg/μm. Both the magnetization and the Faraday rotation angles are somewhat higher than those of polycrystalline BIG thin films prepared by other methods. - Highlights: • Thin film of polycrystalline Bi_3Fe_5O_1_2 was prepared by the mist CVD method. • Optimized conditions were found for the synthesis of single phase of Bi_3Fe_5O_1_2. • The Faraday rotation angle at 633 nm is –5.2 deg/μm at room temperature. • The Faraday rotation is interpreted by the electronic transitions of Fe"3"+ ions.

Removable Thin Films used for the Abatement and Mitigation of Beryllium

International Nuclear Information System (INIS)

Lumia, M.; Gentile, C.; Creek, K.; Sandoval, R.

2003-01-01

The use of removable thin films for the abatement of hazardous particulates has many advantages. Removable thin films are designed to trap and fix particulates in the film's matrix by adhesion. Thin films can be applied to an existing contaminated area to fix and capture the particulates for removal. The nature of the removable thin films, after sufficient cure time, is such that it can typically be removed as one continuous entity. The removable thin films can be applied to almost any surface type with a high success rate of removal

Thermochemical hydrogen generation of indium oxide thin films

Directory of Open Access Journals (Sweden)

Taekyung Lim

2017-03-01

Full Text Available Development of alternative energy resources is an urgent requirement to alleviate current energy constraints. As such, hydrogen gas is gaining attention as a future alternative energy source to address existing issues related to limited energy resources and air pollution. In this study, hydrogen generation by a thermochemical water-splitting process using two types of In2O3 thin films was investigated. The two In2O3 thin films prepared by chemical vapor deposition (CVD and sputtering deposition systems contained different numbers of oxygen vacancies, which were directly related to hydrogen generation. The as-grown In2O3 thin film prepared by CVD generated a large amount of hydrogen because of its abundant oxygen vacancies, while that prepared by sputtering had few oxygen vacancies, resulting in low hydrogen generation. Increasing the temperature of the In2O3 thin film in the reaction chamber caused an increase in hydrogen generation. The oxygen-vacancy-rich In2O3 thin film is expected to provide a highly effective production of hydrogen as a sustainable and efficient energy source.

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.

Room temperature inorganic polycondensation of oxide (Cu{sub 2}O and ZnO) nanoparticles and thin films preparation by the dip-coating technique

Energy Technology Data Exchange (ETDEWEB)

Salek, G.; Tenailleau, C., E-mail: tenailleau@chimie.ups-tlse.fr; Dufour, P.; Guillemet-Fritsch, S.

2015-08-31

Oxide thin solid films were prepared by dip-coating into colloidal dispersions of oxide nanoparticles stabilized at room temperature without the use of chelating or complex organic dispersing agents. Crystalline oxide nanoparticles were obtained by inorganic polycondensation and characterized by X-ray diffraction and field emission gun scanning electron microscopy. Water and ethanol synthesis and solution stabilization of oxide nanoparticle method was optimized to prepare two different structural and compositional materials, namely Cu{sub 2}O and ZnO. The influence of hydrodynamic parameters over the particle shape and size is discussed. Spherical and rod shape nanoparticles were formed for Cu{sub 2}O and ZnO, respectively. Isoelectric point values of 7.5 and 8.2 were determined for cuprous and zinc oxides, respectively, after zeta potential measurements. A shear thinning and thixotropic behavior was observed in both colloidal sols after peptization at pH ~ 6 with dilute nitric acid. Every colloidal dispersion stabilized in a low cost and environmentally friendly azeotrope solution composed of 96 vol.% of ethanol with water was used for the thin film preparation by the dip-coating technique. Optical properties of the light absorber cuprous oxide and transparent zinc oxide thin solid films were characterized by means of transmittance and reflectance measurements (300–1100 nm). - Highlights: • Room temperature inorganic polycondensation of crystalline oxides • Water and ethanol synthesis and solution stabilization of oxide nanoparticles • Low cost method for thin solid film preparation.

Thin film limit correction method to the surface defective layer in low absorption spectroscopy

Czech Academy of Sciences Publication Activity Database

Remeš, Zdeněk; Holovský, Jakub; Purkrt, Adam; Stuchlík, Jiří

2015-01-01

Roč. 7, č. 4 (2015), s. 343-346 ISSN 2164-6627 R&D Projects: GA ČR(CZ) GA14-05053S; GA MŠk(CZ) LD14011 Institutional support: RVO:68378271 Keywords : thin films * optical properties * hydrogenated amorphous silicon * photothermal deflection spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism

Phonon transport across nano-scale curved thin films

Energy Technology Data Exchange (ETDEWEB)

Mansoor, Saad B.; Yilbas, Bekir S., E-mail: bsyilbas@kfupm.edu.sa

2016-12-15

Phonon transport across the curve thin silicon film due to temperature disturbance at film edges is examined. The equation for radiative transport is considered via incorporating Boltzmann transport equation for the energy transfer. The effect of the thin film curvature on phonon transport characteristics is assessed. In the analysis, the film arc length along the film centerline is considered to be constant and the film arc angle is varied to obtain various film curvatures. Equivalent equilibrium temperature is introduced to assess the phonon intensity distribution inside the curved thin film. It is found that equivalent equilibrium temperature decay along the arc length is sharper than that of in the radial direction, which is more pronounced in the region close to the film inner radius. Reducing film arc angle increases the film curvature; in which case, phonon intensity decay becomes sharp in the close region of the high temperature edge. Equivalent equilibrium temperature demonstrates non-symmetric distribution along the radial direction, which is more pronounced in the near region of the high temperature edge.

Phonon transport across nano-scale curved thin films

International Nuclear Information System (INIS)

Mansoor, Saad B.; Yilbas, Bekir S.

2016-01-01

Phonon transport across the curve thin silicon film due to temperature disturbance at film edges is examined. The equation for radiative transport is considered via incorporating Boltzmann transport equation for the energy transfer. The effect of the thin film curvature on phonon transport characteristics is assessed. In the analysis, the film arc length along the film centerline is considered to be constant and the film arc angle is varied to obtain various film curvatures. Equivalent equilibrium temperature is introduced to assess the phonon intensity distribution inside the curved thin film. It is found that equivalent equilibrium temperature decay along the arc length is sharper than that of in the radial direction, which is more pronounced in the region close to the film inner radius. Reducing film arc angle increases the film curvature; in which case, phonon intensity decay becomes sharp in the close region of the high temperature edge. Equivalent equilibrium temperature demonstrates non-symmetric distribution along the radial direction, which is more pronounced in the near region of the high temperature edge.

Emergent Topological Phenomena in Thin Films of Pyrochlore Iridates

Science.gov (United States)

Yang, Bohm-Jung; Nagaosa, Naoto

2014-06-01

Because of the recent development of thin film and artificial superstructure growth techniques, it is possible to control the dimensionality of the system, smoothly between two and three dimensions. In this Letter we unveil the dimensional crossover of emergent topological phenomena in correlated topological materials. In particular, by focusing on the thin film of pyrochlore iridate antiferromagnets grown along the [111] direction, we demonstrate that the thin film can have a giant anomalous Hall conductance, proportional to the thickness of the film, even though there is no Hall effect in 3D bulk material. Moreover, in the case of ultrathin films, a quantized anomalous Hall conductance can be observed, despite the fact that the system is an antiferromagnet. In addition, we uncover the emergence of a new topological phase, the nontrivial topological properties of which are hidden in the bulk insulator and manifest only in thin films. This shows that the thin film of correlated topological materials is a new platform to search for unexplored novel topological phenomena.

Microwave Plasma Chemical Vapor Deposition of Nano-Structured Sn/C Composite Thin-Film Anodes for Li-ion Batteries

Energy Technology Data Exchange (ETDEWEB)

Stevenson, Cynthia; Marcinek, M.; Hardwick, L.J.; Richardson, T.J.; Song, X.; Kostecki, R.

2008-02-01

In this paper we report results of a novel synthesis method of thin-film composite Sn/C anodes for lithium batteries. Thin layers of graphitic carbon decorated with uniformly distributed Sn nanoparticles were synthesized from a solid organic precursor Sn(IV) tert-butoxide by a one step microwave plasma chemical vapor deposition (MPCVD). The thin-film Sn/C electrodes were electrochemically tested in lithium half cells and produced a reversible capacity of 440 and 297 mAhg{sup -1} at C/25 and 5C discharge rates, respectively. A long term cycling of the Sn/C nanocomposite anodes showed 40% capacity loss after 500 cycles at 1C rate.

Influence of the side chain and substrate on polythiophene thin film surface, bulk, and buried interfacial structures.

Science.gov (United States)

Xiao, Minyu; Jasensky, Joshua; Zhang, Xiaoxian; Li, Yaoxin; Pichan, Cayla; Lu, Xiaolin; Chen, Zhan

2016-08-10

The molecular structures of organic semiconducting thin films mediate the performance of various devices composed of such materials. To fully understand how the structures of organic semiconductors alter on substrates due to different polymer side chains and different interfacial interactions, thin films of two kinds of polythiophene derivatives with different side-chains, poly(3-hexylthiophene) (P3HT) and poly(3-potassium-6-hexanoate thiophene) (P3KHT), were deposited and compared on various surfaces. A combination of analytical tools was applied in this research: contact angle goniometry and X-ray photoelectron spectroscopy (XPS) were used to characterize substrate dielectric surfaces with varied hydrophobicity for polymer film deposition; X-ray diffraction and UV-vis spectroscopy were used to examine the polythiophene film bulk structure; sum frequency generation (SFG) vibrational spectroscopy was utilized to probe the molecular structures of polymer film surfaces in air and buried solid/solid interfaces. Both side-chain hydrophobicity and substrate hydrophobicity were found to mediate the crystallinity of the polythiophene film, as well as the orientation of the thiophene ring within the polymer backbone at the buried polymer/substrate interface and the polymer thin film surface in air. For the same type of polythiophene film deposited on different substrates, a more hydrophobic substrate surface induced thiophene ring alignment with the surface normal at both the buried interface and on the surface in air. For different films (P3HT vs. P3KHT) deposited on the same dielectric substrate, a more hydrophobic polythiophene side chain caused the thiophene ring to align more towards the surface at the buried polymer/substrate interface and on the surface in air. We believe that the polythiophene surface, bulk, and buried interfacial molecular structures all influence the hole mobility within the polythiophene film. Successful characterization of an organic conducting

Modeling of thermal, electronic, hydrodynamic, and dynamic deposition processes for pulsed-laser deposition of thin films

International Nuclear Information System (INIS)

Liu, C.L.; LeBoeuf, J.N.; Wood, R.F.; Geohegan, D.B.; Donato, J.M.; Chen, K.R.; Puretzky, A.A.

1994-11-01

Various physical processes during laser ablation of solids for pulsed-laser deposition (PLD) are studied using a variety of computational techniques. In the course of the authors combined theoretical and experimental effort, they have been trying to work on as many aspects of PLD processes as possible, but with special focus on the following areas: (a) the effects of collisional interactions between the particles in the plume and in the background on the evolving flow field and on thin film growth, (b) interactions between the energetic particles and the growing thin films and their effects on film quality, (c) rapid phase transformations through the liquid and vapor phases under possibly nonequilibrium thermodynamic conditions induced by laser-solid interactions, (d) breakdown of the vapor into a plasma in the early stages of ablation through both electronic and photoionization processes, (c) hydrodynamic behavior of the vapor/plasma during and after ablation. The computational techniques used include finite difference (FD) methods, particle-in-cell model, and atomistic simulations using molecular dynamics (MD) techniques

Thermoelectric effects of amorphous Ga-Sn-O thin film

Science.gov (United States)

Matsuda, Tokiyoshi; Uenuma, Mutsunori; Kimura, Mutsumi

2017-07-01

The thermoelectric effects of an amorphous Ga-Sn-O (a-GTO) thin film have been evaluated as a physical parameter of a novel oxide semiconductor. Currently, a-GTO thin films are greatly desired not only because they do not contain rare metals and are therefore free from problems on the exhaustion of resources and the increase in cost but also because their initial characteristics and performance stabilities are excellent when they are used in thin-film transistors. In this study, an a-GTO thin film was deposited on a quartz substrate by RF magnetron sputtering and postannealing was performed in air at 350 °C for 1 h using an annealing furnace. The Seebeck coefficient and electrical conductivity of the a-GTO thin film were -137 µV/K and 31.8 S/cm at room temperature, and -183 µV/K and 43.8 S/cm at 397 K, respectively, and as a result, the power factor was 1.47 µW/(cm·K2) at 397 K; these values were roughly as high as those of amorphous In-Ga-Zn-O (a-IGZO) thin films. Therefore, a-GTO thin films will be a candidate material for thermoelectric devices fabricated in a large area at a low cost by controlling the carrier mobility, carrier density, device structures, and so forth.

Beryllium thin films for resistor applications

Science.gov (United States)

Fiet, O.

1972-01-01

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

XRay Study of Transfer Printed Pentacene Thin Films

International Nuclear Information System (INIS)

Shao, Y.; Solin, S. A.; Hines, D. R.; Williams, E. D.

2007-01-01

We investigated the structural properties and transfer properties of pentacene thin films fabricated by thermal deposition and transfer printing onto SiO2 and plastic substrates, respectively. The dependence of the crystallite size on the printing time, temperature and pressure were measured. The increases of crystalline size were observed when pentacene thin films were printed under specific conditions, e.g. 120 deg. C and 600 psi and can be correlated with the improvement of the field effect mobility of pentacene thin-film transistors

Macro stress mapping on thin film buckling

Energy Technology Data Exchange (ETDEWEB)

Goudeau, P.; Villain, P.; Renault, P.-O.; Tamura, N.; Celestre, R.S.; Padmore, H.A.

2002-11-06

Thin films deposited by Physical Vapour Deposition techniques on substrates generally exhibit large residual stresses which may be responsible of thin film buckling in the case of compressive stresses. Since the 80's, a lot of theoretical work has been done to develop mechanical models but only a few experimental work has been done on this subject to support these theoretical approaches and nothing concerning local stress measurement mainly because of the small dimension of the buckling (few 10th mm). This paper deals with the application of micro beam X-ray diffraction available on synchrotron radiation sources for stress mapping analysis of gold thin film buckling.

Interfacial slippage effect on the surface instability of a thin elastic film under van der Waals force

International Nuclear Information System (INIS)

Pan Xiahui; Yu Shouwen; Feng Xiqiao; Huang Shiqing

2009-01-01

This paper studies the surface instability of an elastic thin solid film lying on a rigid substrate and subjected to van der Waals-like surface interactions. The effect of film-substrate interfacial slippage is accounted for by using a simplified linear cohesive interface model. It is found that the interfacial slippage generally plays a destabilizing role in the surface instability of the thin film. For highly compressible films with Poisson's ratio smaller than 0.25, the surface wrinkling behaviour previously inconceivable in the case of a perfectly bonded interface is now feasible if film-substrate interface slipping is permitted. In addition, our linear perturbation analysis shows that the critical conditions for the onset of surface instability can be modulated by adjusting the slippery stiffness of the interface. The result might be helpful for developing novel techniques to create micro-/nanosized surface patterns.

Theoretical investigation of the thermodynamic properties of metallic thin films

International Nuclear Information System (INIS)

Hung, Vu Van; Phuong, Duong Dai; Hoa, Nguyen Thi; Hieu, Ho Khac

2015-01-01

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

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.

Effect of solution concentration on MEH-PPV thin films

Science.gov (United States)

Affendi, I. H. H.; Sarah, M. S. P.; Alrokayan, Salman A. H.; Khan, Haseeb A.; Rusop, M.

2018-05-01

MEH-PPV thin films were prepared with a mixture of THF (tetrahydrofuran) solution deposited by spin coating method. The surface topology of MEH-PPV thin film were characterize by atomic force microscopy (AFM) and optical properties of absorption spectra were characterized by using Ultraviolet-visible-near-infrared (UV-Vis-NIR). The MEH-PPV concentration variation affects the surface and optical properties of the thin film where 0.5 mg/ml MEH-PPV concentration have a good surface topology provided the same film also gives the highest absorption coefficient were then deposited to a TiO2 thin film forming composite layer. The composite layer then shows low current flow of short circuit current of Isc = -5.313E-7 A.

Far infrared and terahertz spectroscopy of ferroelectric soft modes in thin films: a review

Czech Academy of Sciences Publication Activity Database

Petzelt, Jan; Kamba, Stanislav

2016-01-01

Roč. 503, č. 1 (2016), s. 19-44 ISSN 0015-0193 R&D Projects: GA ČR GA15-08389S Institutional support: RVO:68378271 Keywords : soft mode * central mode * ferroelectric thin film * terahertz spectroscopy * far-infrared spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.551, year: 2016

Thermionic vacuum arc (TVA) technique for magnesium thin film deposition

Energy Technology Data Exchange (ETDEWEB)

Balbag, M.Z., E-mail: zbalbag@ogu.edu.t [Eskisehir Osmangazi University, Education Faculty, Primary Education, Meselik Campus, Eskisehir 26480 (Turkey); Pat, S.; Ozkan, M.; Ekem, N. [Eskisehir Osmangazi University, Art and Science Faculty, Physics Department, Eskisehir 26480 (Turkey); Musa, G. [Ovidius University, Physics Department, Constanta (Romania)

2010-08-15

In this study, magnesium thin films were deposited on glass substrate by the Thermionic Vacuum Arc (TVA) technique for the first time. We present a different technique for deposition of high-quality magnesium thin films. By means of this technique, the production of films is achieved by condensing the plasma of anode material generated using Thermionic Vacuum Arc (TVA) under high vacuum conditions onto the surface to be coated. The crystal orientation and morphology of the deposited films were investigated by using XRD, EDX, SEM and AFM. The aim of this study is to search the use of TVA technique to coat magnesium thin films and to determine some of the physical properties of the films generated. Furthermore, this study will contribute to the scientific studies which search the thin films of magnesium or the compounds containing magnesium. In future, this study will be preliminary work to entirely produce magnesium diboride (MgB{sub 2}) superconductor thin film with the TVA technique.

Perovskite phase thin films and method of making

Science.gov (United States)

Boyle, Timothy J.; Rodriguez, Mark A.

2000-01-01

The present invention comprises perovskite-phase thin films, of the general formula A.sub.x B.sub.y O.sub.3 on a substrate, wherein A is selected from beryllium, magnesium, calcium, strontium, and barium or a combination thereof; B is selected from niobium and tantalum or a combination thereof; and x and y are mole fractions between approximately 0.8 and 1.2. More particularly, A is strontium or barium or a combination thereof and B is niobium or tantalum or a combination thereof. Also provided is a method of making a perovskite-phase thin film, comprising combining at least one element-A-containing compound, wherein A is selected from beryllium, magnesium, calcium, strontium or barium, with at least one element-B-containing compound, wherein B niobium or tantalum, to form a solution; adding a solvent to said solution to form another solution; spin-coating the solution onto a substrate to form a thin film; and heating the film to form the perovskite-phase thin film.

Properties of RF-Sputtered PZT Thin Films with Ti/Pt Electrodes

Directory of Open Access Journals (Sweden)

Cui Yan

2014-01-01

Full Text Available Effect of annealing temperature and thin film thickness on properties of Pb(Zr0.53Ti0.47O3 (PZT thin film deposited via radiofrequency magnetron sputtering technique onto Pt/Ti/SiO2/Si substrate was investigated. Average grain sizes of the PZT thin film were measured by atomic force microscope; their preferred orientation was studied through X-ray diffraction analysis. Average residual stress in the thin film was estimated according to the optimized Stoney formula, and impedance spectroscopy characterization was performed via an intelligent LCR measuring instrument. Average grain sizes of PZT thin films were 60 nm~90 nm and their average roughness was less than 2 nm. According to X-ray diffraction analysis, 600°C is the optimal annealing temperature to obtain the PZT thin film with better crystallization. Average residual stress showed that thermal mismatch was the decisive factor of residual stress in Pt/Ti/SiO2/Si substrate; the residual stress in PZT thin film decreased as their thickness increased and increased with annealing temperature. The dielectric constant and loss angle tangent were extremely increased with the thickness of PZT thin films. The capacitance of the device can be adjusted according to the thickness of PZT thin films.

Substrate-HTcS thin film interaction studies by (S)TEM

NARCIS (Netherlands)

Ramaekers, P.P.J.; Klepper, D.; Kitazawa, K.; Ishiguro, T.

1989-01-01

This paper concerns with compatibility aspects beween HTcS thin film either their substrates. The influence of substrate-thin film interaction and thin film microstructure on the superconducting properties is discussed. In this respect, data based on (S)TEM observations are presented. It is

Low-field vortex dynamics in various high-Tc thin films

Indian Academy of Sciences (India)

Abstract. We present a novel ac susceptibility technique for the study of vortex creep in supercon- ducting thin films. With this technique we study the dynamics of dilute vortices in c-axis oriented. Y-123, Hg-1212, and Tl-1212 thin films, as well as a-axis oriented Hg-1212 thin films. Results on the Hg-1212 and Tl-1212 thin ...

Atomic Structure Control of Silica Thin Films on Pt(111)

KAUST Repository

Crampton, Andrew S

2015-05-27

Metal oxide thin films grown on metal single crystals are commonly used to model heterogeneous catalyst supports. The structure and properties of thin silicon dioxide films grown on metal single crystals have only recently been thoroughly characterized and their spectral properties well established. We report the successful growth of a three- dimensional, vitreous silicon dioxide thin film on the Pt(111) surface and reproduce the closed bilayer structure previously reported. The confirmation of the three dimensional nature of the film is unequivocally shown by the infrared absorption band at 1252 cm−1. Temperature programmed desorption was used to show that this three-dimensional thin film covers the Pt(111) surface to such an extent that its application as a catalyst support for clusters/nanoparticles is possible. The growth of a three-dimensional film was seen to be directly correlated with the amount of oxygen present on the surface after the silicon evaporation process. This excess of oxygen is tentatively attributed to atomic oxygen being generated in the evaporator. The identification of atomic oxygen as a necessary building block for the formation of a three-dimensional thin film opens up new possibilities for thin film growth on metal supports, whereby simply changing the type of oxygen enables thin films with different atomic structures to be synthesized. This is a novel approach to tune the synthesis parameters of thin films to grow a specific structure and expands the options for modeling common amorphous silica supports under ultra high vacuum conditions.

Silicon-integrated thin-film structure for electro-optic applications

Science.gov (United States)

McKee, Rodney A.; Walker, Frederick Joseph

2000-01-01

A crystalline thin-film structure suited for use in any of an number of electro-optic applications, such as a phase modulator or a component of an interferometer, includes a semiconductor substrate of silicon and a ferroelectric, optically-clear thin film of the perovskite BaTiO.sub.3 overlying the surface of the silicon substrate. The BaTiO.sub.3 thin film is characterized in that substantially all of the dipole moments associated with the ferroelectric film are arranged substantially parallel to the surface of the substrate to enhance the electro-optic qualities of the film.

Nitrogen incorporation in sputter deposited molybdenum nitride thin films

Energy Technology Data Exchange (ETDEWEB)

Stöber, Laura, E-mail: laura.stoeber@tuwien.ac.at; Patocka, Florian, E-mail: florian.patocka@tuwien.ac.at; Schneider, Michael, E-mail: michael.schneider@tuwien.ac.at; Schmid, Ulrich, E-mail: ulrich.e366.schmid@tuwien.ac.at [Institute of Sensor and Actuator Systems, TU Wien, Gußhausstraße 27-29, A-1040 Vienna (Austria); Konrath, Jens Peter, E-mail: jenspeter.konrath@infineon.com; Haberl, Verena, E-mail: verena.haberl@infineon.com [Infineon Technologies Austria AG, Siemensstraße 2, 9500 Villach (Austria)

2016-03-15

In this paper, the authors report on the high temperature performance of sputter deposited molybdenum (Mo) and molybdenum nitride (Mo{sub 2}N) thin films. Various argon and nitrogen gas compositions are applied for thin film synthetization, and the amount of nitrogen incorporation is determined by Auger measurements. Furthermore, effusion measurements identifying the binding conditions of the nitrogen in the thin film are performed up to 1000 °C. These results are in excellent agreement with film stress and scanning electron microscope analyses, both indicating stable film properties up to annealing temperatures of 500 °C.

Fabrication and characterization of vacuum deposited fluorescein thin films

Energy Technology Data Exchange (ETDEWEB)

Jalkanen, Pasi, E-mail: pasi.jalkanen@gmail.co [University of Jyvaeskylae, Department of Physics, Nanoscience center (NSC), P.O. Box 35, FI-40014 Jyvaeskylae (Finland); Kulju, Sampo, E-mail: sampo.j.kulju@jyu.f [University of Jyvaeskylae, Department of Physics, Nanoscience center (NSC), P.O. Box 35, FI-40014 Jyvaeskylae (Finland); Arutyunov, Konstantin, E-mail: konstantin.arutyunov@jyu.f [University of Jyvaeskylae, Department of Physics, Nanoscience center (NSC), P.O. Box 35, FI-40014 Jyvaeskylae (Finland); Antila, Liisa, E-mail: liisa.j.antila@jyu.f [University of Jyvaeskylae, Department of Chemistry, Nanoscience center (NSC) P.O. Box 35, FI-40014 Jyvaeskylae (Finland); Myllyperkioe, Pasi, E-mail: pasi.myllyperkio@jyu.f [University of Jyvaeskylae, Department of Chemistry, Nanoscience center (NSC) P.O. Box 35, FI-40014 Jyvaeskylae (Finland); Ihalainen, Teemu, E-mail: teemu.o.ihalainen@jyu.f [University of Jyvaeskylae, Department of Biology, Nanoscience center (NSC), P.O. Box 35, FI-40014 Jyvaeskylae (Finland); Kaeaeriaeinen, Tommi, E-mail: tommi.kaariainen@lut.f [Lappeenranta University of Technology, ASTRal, P.O. Box 181, FI-50101 Mikkeli (Finland); Kaeaeriaeinen, Marja-Leena, E-mail: marja-leena.kaariainen@lut.f [Lappeenranta University of Technology, ASTRal, P.O. Box 181, FI-50101 Mikkeli (Finland); Korppi-Tommola, Jouko, E-mail: jouko.korppi-tommola@jyu.f [University of Jyvaeskylae, Department of Biology, Nanoscience center (NSC), P.O. Box 35, FI-40014 Jyvaeskylae (Finland)

2011-03-31

Simple vacuum evaporation technique for deposition of dyes on various solid surfaces has been developed. The method is compatible with conventional solvent-free nanofabrication processing enabling fabrication of nanoscale optoelectronic devices. Thin films of fluorescein were deposited on glass, fluorine-tin-oxide (FTO) coated glass with and without atomically layer deposited (ALD) nanocrystalline 20 nm thick anatase TiO{sub 2} coating. Surface topology, absorption and emission spectra of the films depend on their thickness and the material of supporting substrate. On a smooth glass surface the dye initially forms islands before merging into a uniform layer after 5 to 10 monolayers. On FTO covered glass the absorption spectra are similar to fluorescein solution in ethanol. Absorption spectra on ALD-TiO{sub 2} is red shifted compared to the film deposited on bare FTO. The corresponding emission spectra at {lambda} = 458 nm excitation show various thickness and substrate dependent features, while the emission of films deposited on TiO{sub 2} is quenched due to the effective electron transfer to the semiconductor conduction band.

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

Science.gov (United States)

Choudhary, Sumita; Narula, Rahul; Gangopadhyay, Subhashis

2018-05-01

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

Optical constant of thin gold films

DEFF Research Database (Denmark)

Yakubovsky, D. I.; Fedyanin, D. Yu; Arsenin, A. V.

2017-01-01

The performance of metal-based devices is limited by ohmic losses in the metal, which are determined by electron scattering. The structural properties of gold thin films also play an important role in the film quality, which may affect its' optical properties and the overall capability...... and spectroscopic ellipsometry, the structural morphology and optical properties of polycrystalline gold thin films (fabricated by e-beam deposition at a low sputtering rate smooth gold) in the thickness range of 20 - 200 nm. By extracting the real and imaginary dielectric function and the Drude parameter...... of the device. At the same time, metal films of different thicknesses are needed for different applications and, since these films are polycrystalline, their internal properties and surface roughness can greatly vary from one thickness to another. In this work, we study, using atomic force microscopy...

Preparation and properties of thin films treatise on materials science and technology

CERN Document Server

Tu, K N

1982-01-01

Treatise on Materials Science and Technology, Volume 24: Preparation and Properties of Thin Films covers the progress made in the preparation of thin films and the corresponding study of their properties. The book discusses the preparation and property correlations in thin film; the variation of microstructure of thin films; and the molecular beam epitaxy of superlattices in thin film. The text also describes the epitaxial growth of silicon structures (thermal-, laser-, and electron-beam-induced); the characterization of grain boundaries in bicrystalline thin films; and the mechanical properti

Thin RuO2 conducting films grown by MOCVD for microelectronic applications

International Nuclear Information System (INIS)

Froehlich, K.; Cambel, V.; Machajdik, D.; Pignard, S.; Baumann, P. K.; Lindner, J.; Schumacher, M.

2002-01-01

We have prepared thin RuO 2 films by MOCVD using thermal evaporation of Ru(thd) 2 (cod) solid precursor. The films were prepared at deposition temperatures between 250 and 500 grad C on silicon and sapphire substrates. Different structure was observed for the RuO 2 films on these substrates; the films on Si substrate were polycrystalline, while X-ray diffraction analysis revealed epitaxial growth of RuO 2 on sapphire substrates. Polycrystalline RuO 2 films prepared at temperatures below 300 grad C on Si substrate exhibit smooth surface and excellent step coverage. Highly conformal growth of the RuO 2 films at low temperature and low pressure results in nearly 100% step coverage for sub-mm features with 1:1 aspect ratio. Resistivity of the polycrystalline RuO 2 at room temperature ranged between 100 and 200 μ x Ω x cm. These films are suitable for CMOS and RAM applications. (Authors)

Effect of the Ultrasonic Substrate Vibration on Nucleation and Crystallization of PbI2 Crystals and Thin Films

Directory of Open Access Journals (Sweden)

Fatemeh Zabihi

2018-01-01

Full Text Available Preparation of defect-free and well-controlled solution-processed crystalline thin films is highly desirable for emerging technologies, such as perovskite solar cells. In this work, using PbI2 as a model solution with a vast variety of applications, we demonstrate that the excitation of a liquid thin film by imposed ultrasonic vibration on the film substrate significantly affects the nucleation and crystallization kinetics of PbI2 and the morphology of the resulting solid thin film. It is found that by applying ultrasonic vibration to PbI2 solution spun onto an ITO substrate with a moderate power and excitation duration (5 W and 1 min for the 40 kHz transducer used in this study, the nucleation rate increases and the crystals transform from 2D or planar to epitaxial 3D columnar structures, resulting in the suppression of crystallization dewetting. The effects of various induced physical phenomena as a result of the excitation by ultrasonic vibration are discussed, including microstreaming and micromixing, increased heat transfer and local temperature, a change in the thermodynamic state of the solution, and a decrease in the supersaturation point. It is shown that the ultrasonic-assisted solution deposition of the PbI2 thin films is controllable and reproducible, a process which is low-cost and in line with the large-scale fabrication of such solution-processed thin films.

Hall effect of K-doped superconducting thin films

Energy Technology Data Exchange (ETDEWEB)

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

2013-09-15

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

Properties of Spray Pyrolysied Copper Oxide Thin Films

Directory of Open Access Journals (Sweden)

S. S. Roy

2017-02-01

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

Laser-induced damage to thin film dielectric coatings

International Nuclear Information System (INIS)

Walker, T.W.

1980-01-01

The laser-induced damage thresholds of dielectric thin film coatings have been found to be more than an order of magnitude lower than the bulk material damage thresholds. Prior damage studies have been inconclusive in determining the damage mechanism which is operative in thin films. A program was conducted in which thin film damage thresholds were measured as a function of laser wavelength (1.06 μm, 0.53 μm, 0.35 μm and 0.26 μm), laser pulse length (5 and 15 nanoseconds), film materials and film thickness. The large matrix of data was compared to predictions given by avalanche ionization, multiphoton ionization and impurity theories of laser damage. When Mie absorption cross-sections and the exact thermal equations were included into the impurity theory excellent agreement with the data was found. The avalanche and multiphoton damage theories could not account for most parametric variations in the data. For example, the damage thresholds for most films increased as the film thickness decreased and only the impurity theory could account for this behavior. Other observed changes in damage threshold with changes in laser wavelength, pulse length and film material could only be adequately explained by the impurity theory. The conclusion which results from this study is that laser damage in thin film coatings results from absorbing impurities included during the deposition process

Physical Vapor Deposition of Thin Films

Science.gov (United States)