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.

Trade-off between Photon Management Efficacy and Material Quality in Thin-Film Solar Cells on Nanostructured Substrates of High Aspect Ratio Structures

Directory of Open Access Journals (Sweden)

Alan H. Chin

2018-04-01

Full Text Available Although texturing of the transparent electrode of thin-film solar cells has long been used to enhance light absorption via light trapping, such texturing has involved low aspect ratio features. With the recent development of nanotechnology, nanostructured substrates enable improved light trapping and enhanced optical absorption via resonances, a process known as photon management, in thin-film solar cells. Despite the progress made in the development of photon management in thin-film solar cells using nanostructures substrates, the structural integrity of the thin-film solar cells deposited onto such nanostructured substrates is rarely considered. Here, we report the observation of the reduction in the open circuit voltage of amorphous silicon solar cells deposited onto a nanostructured substrate with increasing areal number density of high aspect ratio structures. For a nanostructured substrate with the areal number density of such nanostructures increasing in correlation with the distance from one edge of the substrate, a correlation between the open circuit voltage reduction and the increase of the areal number density of high aspect ratio nanostructures of the front electrode of the small-size amorphous silicon solar cells deposited onto different regions of the substrate with graded nanostructure density indicates the effect of the surface morphology on the material quality, i.e., a trade-off between photon management efficacy and material quality. This observed trade-off highlights the importance of optimizing the morphology of the nanostructured substrate to ensure conformal deposition of the thin-film solar cell.

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

Synthesis and characterization of copper antimony tin sulphide thin films for solar cell applications

Energy Technology Data Exchange (ETDEWEB)

Ali, N., E-mail: nisar.ali@utm.my [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor (Malaysia); Department of Physics, Govt. Post Graduate Jehanzeb College Saidu Sharif, Swat, 19200 (Pakistan); Hussain, A. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor (Malaysia); Ahmed, R., E-mail: rashidahmed@utm.my [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor (Malaysia); Wan Shamsuri, W.N. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor (Malaysia); Fu, Y.Q., E-mail: richard.fu@northumbria.ac.uk [Department of Physics and Electrical Engineering, Faculty of Engineering & Environment, University of Northumbria, Newcastle upon Tyne, NE1 8ST (United Kingdom)

2016-12-30

Highlights: • A new and novel material for solar cell applications is demonstrated as a replacement for toxic and expansive compounds. • The materials used in this compound are abundant and low cost. • Compound exhibit unusual optical and electrical properties. • The band gap was found to be comparable with that of GaAs. - Abstract: Low price thin film modules based on Copper antimony tin sulphide (CATS) are introduced for solar harvesting to compete for the already developed compound semiconductors. Here, CATS thin films were deposited on soda lime glass by thermal evaporation technique followed by a rapid thermal annealing in an argon atmosphere. From Our XRD analysis, it was revealed that the annealed samples were poly-crystalline and their crystallinity was improved with increasing annealing temperature. The constituent elements and their corresponding chemical states were identified using X-ray photoelectron spectroscopy. The obtained optical band gap of 1.4 eV for CATS thin film is found nearly equal to GaAs – one of the highly efficient thin film material for solar cell technology. Furthermore, our observed good optical absorbance and low transmittance for the annealed CATS thin films in the visible region of light spectrum assured the aptness of the CATS thin films for solar cell applications.

Perovskite Thin Film Solar Cells Based on Inorganic Hole Conducting Materials

Directory of Open Access Journals (Sweden)

Pan-Pan Zhang

2017-01-01

Full Text Available Organic-inorganic metal halide perovskites have recently shown great potential for application, due to their advantages of low-cost, excellent photoelectric properties and high power conversion efficiency. Perovskite-based thin film solar cells have achieved a power conversion efficiency (PCE of up to 20%. Hole transport materials (HTMs are one of the most important components of perovskite solar cells (PSCs, having functions of optimizing interface, adjusting the energy match, and helping to obtain higher PCE. Inorganic p-type semiconductors are alternative HTMs due to their chemical stability, higher mobility, high transparency in the visible region, and applicable valence band (VB energy level. This review analyzed the advantages, disadvantages, and development prospects of several popular inorganic HTMs in PSCs.

Light-Induced Degradation of Thin Film Silicon Solar Cells

International Nuclear Information System (INIS)

Hamelmann, F U; Weicht, J A; Behrens, G

2016-01-01

Silicon-wafer based solar cells are still domination the market for photovoltaic energy conversion. However, most of the silicon is used only for mechanical stability, while only a small percentage of the material is needed for the light absorption. Thin film silicon technology reduces the material demand to just some hundred nanometer thickness. But even in a tandem stack (amorphous and microcrystalline silicon) the efficiencies are lower, and light-induced degradation is an important issue. The established standard tests for characterisation are not precise enough to predict the performance of thin film silicon solar cells under real conditions, since many factors do have an influence on the degradation. We will show some results of laboratory and outdoor measurements that we are going to use as a base for advanced modelling and simulation methods. (paper)

Progress in Thin Film Solar Cells Based on Cu2ZnSnS4

Directory of Open Access Journals (Sweden)

Hongxia Wang

2011-01-01

Full Text Available The research in thin film solar cells has been dominated by light absorber materials based on CdTe and Cu(In,GaSe2 (CIGS in the last several decades. The concerns of environment impact of cadmium and the limited availability of indium in those materials have driven the research towards developing new substitute light absorbers made from earth abundant, environment benign materials. Cu2ZnSnS4 (CZTS semiconductor material has emerged as one of the most promising candidates for this aim and has attracted considerable interest recently. Significant progress in this relatively new research area has been achieved in the last three years. Over 130 papers on CZTS have been published since 2007, and the majority of them are on the preparation of CZTS thin films by different methods. This paper, will review the wide range of techniques that have been used to deposit CZTS semiconductor thin films. The performance of the thin film solar cells using the CZTS material will also be discussed.

Advances in thin-film solar cells for lightweight space photovoltaic power

Science.gov (United States)

Landis, Geoffrey A.; Bailey, Sheila G.; Flood, Dennis J.

1989-01-01

The development of photovoltaic arrays beyond the next generation is discussed with attention given to the potentials of thin-film polycrystalline and amorphous cells. Of particular importance is the efficiency (the fraction of incident solar energy converted to electricity) and specific power (power to weight ratio). It is found that the radiation tolerance of thin-film materials is far greater than that of single crystal materials. CuInSe2 shows no degradation when exposed to 1-MeV electrons.

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.

Crystalline silicon thin film growth by ECR plasma CVD for solar cells

International Nuclear Information System (INIS)

Licai Wang

1999-07-01

This thesis describes the background, motivation and work carried out towards this PhD programme entitled 'Crystalline Silicon Thin Film Growth by ECR Plasma CVD for Solar Cells'. The fundamental principles of silicon solar cells are introduced with a review of silicon thin film and bulk solar cells. The development and prospects for thin film silicon solar cells are described. Some results of a modelling study on thin film single crystalline solar cells are given which has been carried out using a commercially available solar cell simulation package (PC-1D). This is followed by a description of thin film deposition techniques. These include Chemical Vapour Deposition (CVD) and Plasma-Assisted CVD (PACVD). The basic theory and technology of the emerging technique of Electron Cyclotron Resonance (ECR) PACVD, which was used in this research, are introduced and the potential advantages summarised. Some of the basic methods of material and cell characterisation are briefly described, together with the work carried out in this research. The growth by ECR PACVD at temperatures 2 illumination. The best efficiency in the ECR grown structures was 13.76% using an epitaxial emitter. Cell performance was analysed in detail and the factors controlling performance identified by fitting self-consistently the fight and dark current-voltage and spectral response data using PC-1D. Finally, the conclusions for this research and suggestions for further work are outlined. (author)

Mixed Valence Perovskite Cs2 Au2 I6 : A Potential Material for Thin-Film Pb-Free Photovoltaic Cells with Ultrahigh Efficiency.

Science.gov (United States)

Debbichi, Lamjed; Lee, Songju; Cho, Hyunyoung; Rappe, Andrew M; Hong, Ki-Ha; Jang, Min Seok; Kim, Hyungjun

2018-03-01

New light is shed on the previously known perovskite material, Cs 2 Au 2 I 6 , as a potential active material for high-efficiency thin-film Pb-free photovoltaic cells. First-principles calculations demonstrate that Cs 2 Au 2 I 6 has an optimal band gap that is close to the Shockley-Queisser value. The band gap size is governed by intermediate band formation. Charge disproportionation on Au makes Cs 2 Au 2 I 6 a double-perovskite material, although it is stoichiometrically a single perovskite. In contrast to most previously discussed double perovskites, Cs 2 Au 2 I 6 has a direct-band-gap feature, and optical simulation predicts that a very thin layer of active material is sufficient to achieve a high photoconversion efficiency using a polycrystalline film layer. The already confirmed synthesizability of this material, coupled with the state-of-the-art multiscale simulations connecting from the material to the device, strongly suggests that Cs 2 Au 2 I 6 will serve as the active material in highly efficient, nontoxic, and thin-film perovskite solar cells in the very near future. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Polycaprolactone Thin-Film Micro- and Nanoporous Cell-Encapsulation Devices.

Science.gov (United States)

Nyitray, Crystal E; Chang, Ryan; Faleo, Gaetano; Lance, Kevin D; Bernards, Daniel A; Tang, Qizhi; Desai, Tejal A

2015-06-23

Cell-encapsulating devices can play an important role in advancing the types of tissue available for transplantation and further improving transplant success rates. To have an effective device, encapsulated cells must remain viable, respond to external stimulus, and be protected from immune responses, and the device itself must elicit a minimal foreign body response. To address these challenges, we developed a micro- and a nanoporous thin-film cell encapsulation device from polycaprolactone (PCL), a material previously used in FDA-approved biomedical devices. The thin-film device construct allows long-term bioluminescent transfer imaging, which can be used for monitoring cell viability and device tracking. The ability to tune the microporous and nanoporous membrane allows selective protection from immune cell invasion and cytokine-mediated cell death in vitro, all while maintaining typical cell function, as demonstrated by encapsulated cells' insulin production in response to glucose stimulation. To demonstrate the ability to track, visualize, and monitor the viability of cells encapsulated in implanted thin-film devices, we encapsulated and implanted luciferase-positive MIN6 cells in allogeneic mouse models for up to 90 days. Lack of foreign body response in combination with rapid neovascularization around the device shows promise in using this technology for cell encapsulation. These devices can help elucidate the metrics required for cell encapsulation success and direct future immune-isolation therapies.

Synthesis of Cu2ZnSnS4 thin films by a precursor solution paste for thin film solar cell applications.

Science.gov (United States)

Cho, Jin Woo; Ismail, Agus; Park, Se Jin; Kim, Woong; Yoon, Sungho; Min, Byoung Koun

2013-05-22

Cu2ZnSnS4 (CZTS) is a very promising semiconductor material when used for the absorber layer of thin film solar cells because it consists of only abundant and inexpensive elements. In addition, a low-cost solution process is applicable to the preparation of CZTS absorber films, which reduces the cost when this film is used for the production of thin film solar cells. To fabricate solution-processed CZTS thin film using an easily scalable and relatively safe method, we suggest a precursor solution paste coating method with a two-step heating process (oxidation and sulfurization). The synthesized CZTS film was observed to be composed of grains of a size of ~300 nm, showing an overall densely packed morphology with some pores and voids. A solar cell device with this film as an absorber layer showed the highest efficiency of 3.02% with an open circuit voltage of 556 mV, a short current density of 13.5 mA/cm(2), and a fill factor of 40.3%. We also noted the existence of Cd moieties and an inhomogeneous Zn distribution in the CZTS film, which may have been triggered by the presence of pores and voids in the CZTS film.

Cell adhesion on NiTi thin film sputter-deposited meshes

Energy Technology Data Exchange (ETDEWEB)

Loger, K. [Inorganic Functional Materials, Institute for Materials Science, Faculty of Engineering, University of Kiel (Germany); Engel, A.; Haupt, J. [Department of Cardiovascular Surgery, University Hospital of Schleswig-Holstein, Kiel (Germany); Li, Q. [Biocompatible Nanomaterials, Institute for Materials Science, Faculty of Engineering, University of Kiel (Germany); Lima de Miranda, R. [Inorganic Functional Materials, Institute for Materials Science, Faculty of Engineering, University of Kiel (Germany); ACQUANDAS GmbH, Kiel (Germany); Quandt, E. [Inorganic Functional Materials, Institute for Materials Science, Faculty of Engineering, University of Kiel (Germany); Lutter, G. [Department of Cardiovascular Surgery, University Hospital of Schleswig-Holstein, Kiel (Germany); Selhuber-Unkel, C. [Biocompatible Nanomaterials, Institute for Materials Science, Faculty of Engineering, University of Kiel (Germany)

2016-02-01

Scaffolds for tissue engineering enable the possibility to fabricate and form biomedical implants in vitro, which fulfill special functionality in vivo. In this study, free-standing Nickel–Titanium (NiTi) thin film meshes were produced by means of magnetron sputter deposition. Meshes contained precisely defined rhombic holes in the size of 440 to 1309 μm{sup 2} and a strut width ranging from 5.3 to 9.2 μm. The effective mechanical properties of the microstructured superelastic NiTi thin film were examined by tensile testing. These results will be adapted for the design of the holes in the film. The influence of hole and strut dimensions on the adhesion of sheep autologous cells (CD133 +) was studied after 24 h and after seven days of incubation. Optical analysis using fluorescence microscopy and scanning electron microscopy showed that cell adhesion depends on the structural parameters of the mesh. After 7 days in cell culture a large part of the mesh was covered with aligned fibrous material. Cell adhesion is particularly facilitated on meshes with small rhombic holes of 440 μm{sup 2} and a strut width of 5.3 μm. Our results demonstrate that free-standing NiTi thin film meshes have a promising potential for applications in cardiovascular tissue engineering, particularly for the fabrication of heart valves. - Highlights: • Freestanding NiTi thin film scaffolds were fabricated with magnetron sputtering process. • Effective mechanical properties of NiTi scaffolds can be adapted by the mesh structure parameters. • Cell adhesion on the NiTi thin film scaffold is controlled by the structure parameters of the mesh. • Cells strongly adhere after seven days and form a confluent layer on the mesh.

Cell adhesion on NiTi thin film sputter-deposited meshes

International Nuclear Information System (INIS)

Loger, K.; Engel, A.; Haupt, J.; Li, Q.; Lima de Miranda, R.; Quandt, E.; Lutter, G.; Selhuber-Unkel, C.

2016-01-01

Scaffolds for tissue engineering enable the possibility to fabricate and form biomedical implants in vitro, which fulfill special functionality in vivo. In this study, free-standing Nickel–Titanium (NiTi) thin film meshes were produced by means of magnetron sputter deposition. Meshes contained precisely defined rhombic holes in the size of 440 to 1309 μm 2 and a strut width ranging from 5.3 to 9.2 μm. The effective mechanical properties of the microstructured superelastic NiTi thin film were examined by tensile testing. These results will be adapted for the design of the holes in the film. The influence of hole and strut dimensions on the adhesion of sheep autologous cells (CD133 +) was studied after 24 h and after seven days of incubation. Optical analysis using fluorescence microscopy and scanning electron microscopy showed that cell adhesion depends on the structural parameters of the mesh. After 7 days in cell culture a large part of the mesh was covered with aligned fibrous material. Cell adhesion is particularly facilitated on meshes with small rhombic holes of 440 μm 2 and a strut width of 5.3 μm. Our results demonstrate that free-standing NiTi thin film meshes have a promising potential for applications in cardiovascular tissue engineering, particularly for the fabrication of heart valves. - Highlights: • Freestanding NiTi thin film scaffolds were fabricated with magnetron sputtering process. • Effective mechanical properties of NiTi scaffolds can be adapted by the mesh structure parameters. • Cell adhesion on the NiTi thin film scaffold is controlled by the structure parameters of the mesh. • Cells strongly adhere after seven days and form a confluent layer on the mesh.

Development of CIGS2 thin film solar cells

International Nuclear Information System (INIS)

Dhere, Neelkanth G.; Gade, Vivek S.; Kadam, Ankur A.; Jahagirdar, Anant H.; Kulkarni, Sachin S.; Bet, Sachin M.

2005-01-01

Research and development of CuIn 1-x Ga x Se 2-y S y (CIGSS) thin-film solar cells on ultralightweight flexible metallic foil substrates is being carried out at FSEC PV Materials Lab for space applications. Earlier, the substrate size was limited to 3 cm x 2.5 cm. Large-area sputtering systems and scrubber for hydrogen selenide and sulfide have been designed and constructed for preparation of CIGSS thin-films on large (15 cm x 10 cm) substrates. A selenization/sulfurization furnace donated by Shell (formerly Siemens) Solar has also been refurbished and upgraded. The sputtering target assembly design was modified for proper clamping of targets and effective cooling. A new design of the magnetic assembly for large-area magnetron sputtering sources was implemented so as to achieve uniform deposition on large area. Lightweight stainless steel foil and ultralightweight titanium foil substrates were utilized to increase the specific power of solar cells. Sol-gel derived SiO 2 layers were coated on titanium foil by dip coating method. Deposition parameters for the preparation of molybdenum back contact layers were optimized so as to minimize the residual stress as well as reaction with H 2 S. Presently large (15 cm x 10 cm) CuIn 1-x Ga x S 2 (CIGS2) thin film solar cells are being prepared on Mo-coated titanium and stainless steel foil by sulfurization of CuGa/In metallic precursors in diluted Ar:H 2 S(4%). Heterojunction partner CdS layers are deposited by chemical bath deposition. The regeneration sequence of ZnO/ZnO:Al targets was optimized for obtaining consistently good-quality, transparent and conducting ZnO/ZnO:Al bilayer by RF magnetron-sputter deposition. Excellent facilities at FSEC PV Materials Lab are one of its kinds and could serve as a nucleus of a small pilot plant for CIGSS thin film solar cell fabrication

Materials and Light Management for High-Efficiency Thin-Film Silicon Solar Cells

NARCIS (Netherlands)

Tan, H.

2015-01-01

Direct conversion of sunlight into electricity is one of the most promising approaches to provide sufficient renewable energy for humankind. Solar cells are such devices which can efficiently generate electricity from sunlight through the photovoltaic effect. Thin-film silicon solar cells, a type of

Progress in Polycrystalline Thin-Film Cu(In,GaSe2 Solar Cells

Directory of Open Access Journals (Sweden)

Udai P. Singh

2010-01-01

Full Text Available For some time, the chalcopyrite semiconductor CuInSe2 and its alloy with Ga and/or S [Cu(InGaSe2 or Cu(InGa(Se,S2], commonly referred as CIGS, have been leading thin-film material candidates for incorporation in high-efficiency photovoltaic devices. CuInSe2-based solar cells have shown long-term stability and the highest conversion efficiencies among all thin-film solar cells, reaching 20%. A variety of methods have been reported to prepare CIGS thin film. Efficiency of solar cells depends upon the various deposition methods as they control optoelectronic properties of the layers and interfaces. CIGS thin film grown on glass or flexible (metal foil, polyimide substrates require p-type absorber layers of optimum optoelectronic properties and n-type wideband gap partner layers to form the p-n junction. Transparent conducting oxide and specific metal layers are used for front and back contacts. Progress made in the field of CIGS solar cell in recent years has been reviewed.

Low cost thin film poly-silicon solar cells

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

This report presents the results of a project to design and develop a high density plasma based thin-film poly-silicon (TFPS) deposition system based on PQL proprietary advanced plasma technology to produce semiconductor quality TFPS for fabricating a TFPS solar cell. Details are given of the TFPS deposition system, the material development programme, solar cell structure, and cell efficiencies. The reproducibility of the deposition process and prospects for commercial exploitation are discussed.

Paths to light trapping in thin film GaAs solar cells.

Science.gov (United States)

Xiao, Jianling; Fang, Hanlin; Su, Rongbin; Li, Kezheng; Song, Jindong; Krauss, Thomas F; Li, Juntao; Martins, Emiliano R

2018-03-19

It is now well established that light trapping is an essential element of thin film solar cell design. Numerous light trapping geometries have already been applied to thin film cells, especially to silicon-based devices. Less attention has been paid to light trapping in GaAs thin film cells, mainly because light trapping is considered less attractive due to the material's direct bandgap and the fact that GaAs suffers from strong surface recombination, which particularly affects etched nanostructures. Here, we study light trapping structures that are implemented in a high-bandgap material on the back of the GaAs active layer, thereby not perturbing the integrity of the GaAs active layer. We study photonic crystal and quasi-random nanostructures both by simulation and by experiment and find that the photonic crystal structures are superior because they exhibit fewer but stronger resonances that are better matched to the narrow wavelength range where GaAs benefits from light trapping. In fact, we show that a 1500 nm thick cell with photonic crystals achieves the same short circuit current as an unpatterned 4000 nm thick cell. These findings are significant because they afford a sizeable reduction in active layer thickness, and therefore a reduction in expensive epitaxial growth time and cost, yet without compromising performance.

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...

Silver Nanoparticle Enhanced Freestanding Thin-Film Silicon Solar Cells

Science.gov (United States)

Winans, Joshua David

As the supply of fossil fuels diminishes in quantity the demand for alternative energy sources will consistently increase. Solar cells are an environmentally friendly and proven technology that suffer in sales due to a large upfront cost. In order to help facilitate the transition from fossil fuels to photovoltaics, module costs must be reduced to prices well below $1/Watt. Thin-film solar cells are more affordable because of the reduced materials costs, but lower in efficiency because less light is absorbed before passing through the cell. Silver nanoparticles placed at the front surface of the solar cell absorb and reradiate the energy of the light in ways such that more of the light ends being captured by the silicon. Silver nanoparticles can do this because they have free electron clouds that can take on the energy of an incident photon through collective action. This bulk action of the electrons is called a plasmon. This work begins by discussing the economics driving the need for reduced material use, and the pros and cons of taking this step. Next, the fundamental theory of light-matter interaction is briefly described followed by an introduction to the study of plasmonics. Following that we discuss a traditional method of silver nanoparticle formation and the initial experimental studies of their effects on the ability of thin-film silicon to absorb light. Then, Finite-Difference Time-Domain simulation software is used to simulate the effects of nanoparticle morphology and size on the scattering of light at the surface of the thin-film.

Cell adhesion to cathodic arc plasma deposited CrAlSiN thin films

Energy Technology Data Exchange (ETDEWEB)

Kim, Sun Kyu, E-mail: skim@ulsan.ac.kr [School of Materials Science and Engineering, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Pham, Vuong-Hung [Department of Materials Science and Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Kim, Chong-Hyun [Department of Food Science, Cornell University, Ithaca, NY 14853 (United States)

2012-07-01

Osteoblast cell response (cell adhesion, actin cytoskeleton and focal contact adhesion as well as cell proliferation) to CrN, CrAlSiN and Ti thin films was evaluated in vitro. Cell adhesion and actin stress fibers organization depended on the film composition significantly. Immunofluorescent staining of vinculin in osteoblast cells showed good focal contact adhesion on the CrAlSiN and Ti thin films but not on the CrN thin films. Cell proliferation was significantly greater on the CrAlSiN thin films as well as on Ti thin films than on the CrN thin films.

Materials science in microelectronics I the relationships between thin film processing and structure

CERN Document Server

Machlin, Eugene

2005-01-01

Thin films play a key role in the material science of microelectronics, and the subject matter of thin-films divides naturally into two headings: processing / structure relationship, and structure / properties relationship.The first volume of Materials Science in Microelectronics focuses on the first relationship - that between processing and the structure of the thin-film. The state of the thin film's surface during the period that one monolayer exists - before being buried in the next layer - determines the ultimate structure of the thin film, and thus its properties. This

Thin film solar cell technology in Germany

International Nuclear Information System (INIS)

Diehl, W.; Sittinger, V.; Szyszka, B.

2005-01-01

Within the scope of limited nonrenewable energy resources and the limited capacity of the ecosystem for greenhouse gases and nuclear waste, sustainability is one important target in the future. Different energy scenarios showed the huge potential for photovoltaics (PV) to solve this energy problem. Nevertheless, in the last decade, PV had an average growth rate of over 20% per year. In 2002, the solar industry delivered more than 500 MWp/year of photovoltaic generators [A. Jaeger-Waldau, A European Roadmap for PV R and D, E-MRS Spring Meeting, (2003)]. More than 85% of the current production involves crystalline silicon technologies. These technologies still have a high cost reduction potential, but this will be limited by the silicon feedstock. On the other hand the so-called second generation thin film solar cells based on a-Si, Cu(In,Ga)(Se,S 2 (CIGS) or CdTe have material thicknesses of a few microns as a result of their direct band gap. Also, the possibility of circuit integration offers an additional cost reduction potential. Especially in Germany, there are a few companies who focus on thin film solar cells. Today, there are two manufacturers with production lines: the Phototronics (PST) division of RWE-Schott Solar with a-Si thin film technology and the former Antec Solar GmbH (now Antec Solar Energy GmbH) featuring the CdTe technology. A pilot line based on CIGS technology is run by Wuerth Solar GmbH. There is also a variety of research activity at other companies, namely, at Shell Solar, Sulfurcell Solartechnik GmbH, Solarion GmbH and the CIS-Solartechnik GmbH. We will give an overview on research activity on various thin film technologies, as well as different manufacturing and production processes in the companies mentioned above. (Author)

High-throughput characterization of film thickness in thin film materials libraries by digital holographic microscopy

International Nuclear Information System (INIS)

Lai Yiuwai; Hofmann, Martin R; Ludwig, Alfred; Krause, Michael; Savan, Alan; Thienhaus, Sigurd; Koukourakis, Nektarios

2011-01-01

A high-throughput characterization technique based on digital holography for mapping film thickness in thin-film materials libraries was developed. Digital holographic microscopy is used for fully automatic measurements of the thickness of patterned films with nanometer resolution. The method has several significant advantages over conventional stylus profilometry: it is contactless and fast, substrate bending is compensated, and the experimental setup is simple. Patterned films prepared by different combinatorial thin-film approaches were characterized to investigate and demonstrate this method. The results show that this technique is valuable for the quick, reliable and high-throughput determination of the film thickness distribution in combinatorial materials research. Importantly, it can also be applied to thin films that have been structured by shadow masking.

High-throughput characterization of film thickness in thin film materials libraries by digital holographic microscopy.

Science.gov (United States)

Lai, Yiu Wai; Krause, Michael; Savan, Alan; Thienhaus, Sigurd; Koukourakis, Nektarios; Hofmann, Martin R; Ludwig, Alfred

2011-10-01

A high-throughput characterization technique based on digital holography for mapping film thickness in thin-film materials libraries was developed. Digital holographic microscopy is used for fully automatic measurements of the thickness of patterned films with nanometer resolution. The method has several significant advantages over conventional stylus profilometry: it is contactless and fast, substrate bending is compensated, and the experimental setup is simple. Patterned films prepared by different combinatorial thin-film approaches were characterized to investigate and demonstrate this method. The results show that this technique is valuable for the quick, reliable and high-throughput determination of the film thickness distribution in combinatorial materials research. Importantly, it can also be applied to thin films that have been structured by shadow masking.

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

II-IV-V Based Thin Film Tandem Photovoltaic Cell

Energy Technology Data Exchange (ETDEWEB)

Newman, Nathan [Arizona State Univ., Mesa, AZ (United States); van Schilfgaarde, Mark [Arizona State Univ., Mesa, AZ (United States)

2012-10-04

[Through a combination of theory and experiment that, absent unknown mitigating factors, a tandem cell whose (wide-gap. 1.8 eV) top layer is made of ZnSnP2 and whose (narrow gap, 1.1 eV) bottom layer consisting of ZnGeAs2 are near-ideal materials for a tandem cell. Not only are there gaps optimally adjusted to the solar spectrum, but the two compounds are lattice-matched, and their energy band structure and optical absorption are also near-ideal (they closely resemble that of GaAs). Our first major challenge is to establish that high-quality II-IV-V thin films can be synthesized. We have begun growing and characterizing films of ZnGeAs2 and ZnSnP2, initially grown on Ge substrates (the lattice constant of Ge matches these compounds) by pulsed laser ablation and sputtering. In tandem are theoretical calculations to guide the experiments. The goal is to develop methods that can be used to produce a pair of lattice-matched thin films that will be useful in tandem cells.

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

Improvements in CdTe- and CIGS-based thin-film solar cells and investigation on new materials for photovoltaic applications.

OpenAIRE

Rosa, Greta

2018-01-01

Currently, thin-film solar cells are one of the most promising technologies for low-cost renewable energy production. CdTe- and CuInGaSe2-based cells, which achieved record efficiencies of 22.1% and 22.6% respectively, are the most attractive among thin-film solar cells. These high efficiencies have had a huge influence in making them highly competitive in the photovoltaic market, with an estimated final cost per module lower than US $ 0.50 per peak-watt. At the Thin Film Laboratory of the...

Analytical techniques for thin films treatise on materials science and technology

CERN Document Server

Tu, K N

1988-01-01

Treatise on Materials Science and Technology, Volume 27: Analytical Techniques for Thin Films covers a set of analytical techniques developed for thin films and interfaces, all based on scattering and excitation phenomena and theories. The book discusses photon beam and X-ray techniques; electron beam techniques; and ion beam techniques. Materials scientists, materials engineers, chemical engineers, and physicists will find the book invaluable.

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

Plasmonic versus dielectric enhancement in thin-film solar cells

DEFF Research Database (Denmark)

Dühring, Maria Bayard; Mortensen, N. Asger; Sigmund, Ole

2012-01-01

to its metallic counterpart. We show that the enhanced normalized short-circuit current for a cell with silicon strips can be increased 4 times compared to the best performance for strips of silver, gold, or aluminium. For this particular case, the simple dielectric grating may outperform its plasmonic......Several studies have indicated that broadband absorption of thin-film solar cells can be enhanced by use of surface-plasmon induced resonances of metallic parts like strips or particles. The metallic parts may create localized modes or scatter incoming light to increase absorption in thin......-film semiconducting material. For a particular case, we show that coupling to the same type of localized slab-waveguide modes can be obtained by a surface modulation consisting of purely dielectric strips. The purely dielectric device turns out to have a significantly higher broadband enhancement factor compared...

Silk fibroin/chitosan thin film promotes osteogenic and adipogenic differentiation of rat bone marrow-derived mesenchymal stem cells.

Science.gov (United States)

Li, Da-Wei; He, Jin; He, Feng-Li; Liu, Ya-Li; Liu, Yang-Yang; Ye, Ya-Jing; Deng, Xudong; Yin, Da-Chuan

2018-04-01

As a biodegradable polymer thin film, silk fibroin/chitosan composite film overcomes the defects of pure silk fibroin and chitosan films, respectively, and shows remarkable biocompatibility, appropriate hydrophilicity and mechanical properties. Silk fibroin/chitosan thin film can be used not only as metal implant coating for bone injury repair, but also as tissue engineering scaffold for skin, cornea, adipose, and other soft tissue injury repair. However, the biocompatibility of silk fibroin/chitosan thin film for mesenchymal stem cells, a kind of important seed cell of tissue engineering and regenerative medicine, is rarely reported. In this study, silk fibroin/chitosan film was prepared by solvent casting method, and the rat bone marrow-derived mesenchymal stem cells were cultured on the silk fibroin/chitosan thin film. Osteogenic and adipogenic differentiation of rat bone marrow-derived mesenchymal stem cells were induced, respectively. The proliferation ability, osteogenic and adipogenic differentiation abilities of rat bone marrow-derived mesenchymal stem cells were systematically compared between silk fibroin/chitosan thin film and polystyrene tissue culture plates. The results showed that silk fibroin/chitosan thin film not only provided a comparable environment for the growth and proliferation of rat bone marrow-derived mesenchymal stem cells but also promoted their osteogenic and adipogenic differentiation. This work provided information of rat bone marrow-derived mesenchymal stem cells behavior on silk fibroin/chitosan thin film and extended the application of silk fibroin/chitosan thin film. Based on the results, we suggested that the silk fibroin/chitosan thin film could be a promising material for tissue engineering of bone, cartilage, adipose, and skin.

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.

Commercial Development Of Ovonic Thin Film Solar Cells

Science.gov (United States)

Ovshinsky, Stanford R.

1983-09-01

subsequent paper) which has clearly demonstrated that the basic barrier to low-cost production has been broken through and that one can now speak realistically of delivering power directly from the sun for under a dollar per peak watt merely by making larger versions of this basic continuous web, large-area thin-film machine. We have made one square foot amorphous silicon alloy PIN devices with conversion efficiencies in the range of 7%, and in the laboratory, we have reported smaller area PIN de-vices in the 10% conversion efficiency range. In addition, much higher energy conversion efficiencies can be obtained within the same process by using multi-cell layered or tandem thin-film solar cell structures (see Figure 1). These devices exhibit enhanced efficiency by utilizing a wider range of the solar spectrum. Since the theoretical maximum efficiency for multi-cell structures is over 60%, one can certainly realistically anticipate the pro-duction of thin-film amorphous photovoltaic devices with efficiencies as high as 30%. Our production device is already a two-cell tandem, as we have solved not only the problems of interfacing the individual cell components but also the difficulties associated with a one foot square format deposited on a continuous web. Figure 2 shows a continuous roll of Ovonic solar cells. Realistic calculations for a three-cell tandem thin-film device using amorphous semiconductor alloys with 1.8eV, 1.5eV, and 1.0eV optical band gaps indicate that solar energy conversion efficiencies of 20-30% can be achieved.

Atmospheric-Pressure-Spray, Chemical- Vapor-Deposited Thin-Film Materials Being Developed for High Power-to- Weight-Ratio Space Photovoltaic Applications

Science.gov (United States)

Hepp, Aloysius F.; Harris, Jerry D.; Raffaelle, Ryne P.; Banger, Kulbinder K.; Smith, Mark A.; Cowen, Jonathan E.

2001-01-01

The key to achieving high specific power (watts per kilogram) space photovoltaic arrays is the development of high-efficiency thin-film solar cells that are fabricated on lightweight, space-qualified substrates such as Kapton (DuPont) or another polymer film. Cell efficiencies of 20 percent air mass zero (AM0) are required. One of the major obstacles to developing lightweight, flexible, thin-film solar cells is the unavailability of lightweight substrate or superstrate materials that are compatible with current deposition techniques. There are two solutions for working around this problem: (1) develop new substrate or superstrate materials that are compatible with current deposition techniques, or (2) develop new deposition techniques that are compatible with existing materials. The NASA Glenn Research Center has been focusing on the latter approach and has been developing a deposition technique for depositing thin-film absorbers at temperatures below 400 C.

Thin Film Solar Cells and their Optical Properties

Directory of Open Access Journals (Sweden)

Stanislav Jurecka

2006-01-01

Full Text Available In this work we report on the optical parameters of the semiconductor thin film for solar cell applications determination. The method is based on the dynamical modeling of the spectral reflectance function combined with the stochastic optimization of the initial reflectance model estimation. The spectral dependency of the thin film optical parameters computations is based on the optical transitions modeling. The combination of the dynamical modeling and the stochastic optimization of the initial theoretical model estimation enable comfortable analysis of the spectral dependencies of the optical parameters and incorporation of the microstructure effects on the solar cell properties. The results of the optical parameters ofthe i-a-Si thin film determination are presented.

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

Science.gov (United States)

Rajanikant, Ray Jayminkumar

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

Method for preparing microstructure arrays on the surface of thin film material

KAUST Repository

Wang, Peng; Tang, Bo; Zhang, Lianbin

2017-01-01

Methods are provided for growing a thin film of a nanoscale material. Thin films of nanoscale materials are also provided. The films can be grown with microscale patterning. The method can include vacuum filtration of a solution containing the nanostructured material through a porous substrate. The porous substrate can have a pore size that is comparable to the size of the nanoscale material. By patterning the pores on the surface of the substrate, a film can be grown having the pattern on a surface of the thin film, including on the top surface opposite the substrate. The nanoscale material can be graphene, graphene oxide, reduced graphene oxide, molybdenum disulfide, hexagonal boron nitride, tungsten diselenide, molybdenum trioxide, or clays such as montmorillonite or lapnotie. The porous substrate can be a porous organic or inorganic membrane, a silicon stencil membrane, or similar membrane having pore sizes on the order of microns.

Method for preparing microstructure arrays on the surface of thin film material

KAUST Repository

Wang, Peng

2017-02-09

Methods are provided for growing a thin film of a nanoscale material. Thin films of nanoscale materials are also provided. The films can be grown with microscale patterning. The method can include vacuum filtration of a solution containing the nanostructured material through a porous substrate. The porous substrate can have a pore size that is comparable to the size of the nanoscale material. By patterning the pores on the surface of the substrate, a film can be grown having the pattern on a surface of the thin film, including on the top surface opposite the substrate. The nanoscale material can be graphene, graphene oxide, reduced graphene oxide, molybdenum disulfide, hexagonal boron nitride, tungsten diselenide, molybdenum trioxide, or clays such as montmorillonite or lapnotie. The porous substrate can be a porous organic or inorganic membrane, a silicon stencil membrane, or similar membrane having pore sizes on the order of microns.

Research progress of VO2 thin film as laser protecting material

Science.gov (United States)

Liu, Zhiwei; Lu, Yuan; Hou, Dianxin

2018-03-01

With the development of laser technology, the battlefield threat of directional laser weapons is becoming more and more serious. The blinding and destruction caused by laser weapons on the photoelectric equipment is an important part of the current photo-electronic warfare. The research on the defense technology of directional laser weapons based on the phase transition characteristics of VO2 thin films is an important subject. The researches of VO2 thin films are summarized based on review these points: the preparation methods of VO2 thin films, phase transition mechanism, phase transition temperature regulating, interaction between VO2 thin films and laser, and the application prospect of vo2 thin film as laser protecting material. This paper has some guiding significance for further research on the VO2 thin films in the field of defense directional laser weapons.

Silicon Thin-Film Solar Cells

Directory of Open Access Journals (Sweden)

Guy Beaucarne

2007-01-01

with plasma-enhanced chemical vapor deposition (PECVD. In spite of the fundamental limitation of this material due to its disorder and metastability, the technology is now gaining industrial momentum thanks to the entry of equipment manufacturers with experience with large-area PECVD. Microcrystalline Si (also called nanocrystalline Si is a material with crystallites in the nanometer range in an amorphous matrix, and which contains less defects than amorphous silicon. Its lower bandgap makes it particularly appropriate as active material for the bottom cell in tandem and triple junction devices. The combination of an amorphous silicon top cell and a microcrystalline bottom cell has yielded promising results, but much work is needed to implement it on large-area and to limit light-induced degradation. Finally thin-film polysilicon solar cells, with grain size in the micrometer range, has recently emerged as an alternative photovoltaic technology. The layers have a grain size ranging from 1 μm to several tens of microns, and are formed at a temperature ranging from 600 to more than 1000∘C. Solid Phase Crystallization has yielded the best results so far but there has recently been fast progress with seed layer approaches, particularly those using the aluminum-induced crystallization technique.

High mobility transparent conducting oxides for thin film solar cells

International Nuclear Information System (INIS)

Calnan, S.; Tiwari, A.N.

2010-01-01

A special class of transparent conducting oxides (TCO) with high mobility of > 65 cm 2 V -1 s -1 allows film resistivity in the low 10 -4 Ω cm range and a high transparency of > 80% over a wide spectrum, from 300 nm to beyond 1500 nm. This exceptional coincidence of desirable optical and electrical properties provides opportunities to improve the performance of opto-electronic devices and opens possibilities for new applications. Strategies to attain high mobility (HM) TCO materials as well as the current status of such materials based on indium and cadmium containing oxides are presented. Various concepts used to understand the underlying mechanisms for high mobility in HMTCO films are discussed. Examples of HMTCO layers used as transparent electrodes in thin film solar cells are used to illustrate possible improvements in solar cell performance. Finally, challenges and prospects for further development of HMTCO materials are discussed.

Cell culture arrays using micron-sized ferromagnetic ring-shaped thin films

Energy Technology Data Exchange (ETDEWEB)

Huang, Chen-Yu; Wei, Zung-Hang, E-mail: wei@pme.nthu.edu.tw [Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu City 300, Taiwan (China); Lai, Mei-Feng; Ger, Tzong-Rong [Institute of NanoEngineering and MicroSystems, National Tsing Hua University, Hsinchu City 300, Taiwan (China)

2015-05-07

Cell patterning has become an important technology for tissue engineering. In this research, domain walls are formed at the two ends of a ferromagnetic ring thin film after applying a strong external magnetic field, which can effectively attract magnetically labeled cells and control the position for biological cell. Magnetophoresis experiment was conducted to quantify the magnetic nanoparticle inside the cells. A ring-shaped magnetic thin films array was fabricated through photolithography. It is observed that magnetically labeled cells can be successfully attracted to the two ends of the ring-shaped magnetic thin film structure and more cells were attracted and further attached to the structures. The cells are co-cultured with the structure and kept proliferating; therefore, such ring thin film can be an important candidate for in-vitro biomedical chips or tissue engineering.

Cell culture arrays using micron-sized ferromagnetic ring-shaped thin films

International Nuclear Information System (INIS)

Huang, Chen-Yu; Wei, Zung-Hang; Lai, Mei-Feng; Ger, Tzong-Rong

2015-01-01

Cell patterning has become an important technology for tissue engineering. In this research, domain walls are formed at the two ends of a ferromagnetic ring thin film after applying a strong external magnetic field, which can effectively attract magnetically labeled cells and control the position for biological cell. Magnetophoresis experiment was conducted to quantify the magnetic nanoparticle inside the cells. A ring-shaped magnetic thin films array was fabricated through photolithography. It is observed that magnetically labeled cells can be successfully attracted to the two ends of the ring-shaped magnetic thin film structure and more cells were attracted and further attached to the structures. The cells are co-cultured with the structure and kept proliferating; therefore, such ring thin film can be an important candidate for in-vitro biomedical chips or tissue engineering

Failure and fracture of thin film materials for MEMS

Science.gov (United States)

Jonnalagadda, Krishna Nagasai

Design and reliable operation of Microelectromechanical systems (MEMS) depend on the material parameters that influence the failure and fracture properties of brittle and metallic thin films. Failure in brittle materials is quantified by the onset of catastrophic fracture, while in metals, the onset of inelastic deformation is considered as failure as it increases the material compliance. This dissertation research developed new experimental methods to address three aspects on the failure response of these two categories of materials: (a) the role of microstructure and intrinsic stress gradients in the opening mode fracture of mathematically sharp pre-cracks in amorphous and polycrystalline brittle thin films, (b) the critical conditions for mixed mode I/II pre-cracks and their comparison with linear elastic fracture mechanics (LEFM) criteria for crack initiation in homogeneous materials, and (c) the strain rate sensitivity of textured nanocrystalline Au and Pt films with grain sizes of 38 nm and 25 nm respectively. One of the technical objectives of this research was to develop experimental methods and tools that could become standards in MEMS and thin film experimental mechanics. In this regard, a new method was introduced to conduct mode I and mixed mode I/II fracture studies with microscale thin film specimens containing sharp edge pre-cracks. The mode I experiments permitted the direct application of LEFM handbook solutions. On the other hand, the newly introduced mixed mode I/II experiments in thin films were conducted by establishing a new protocol that employs non-standard oblique edge pre-cracks and a numerical analysis based on the J-integral to calculate the stress intensity factors. Similarly, a new experimental protocol has been implemented to carry out experiments with metallic thin films at strain rates that vary by more than six orders of magnitude. The results of mode I fracture experiments concluded that grain inhomogeneity in polycrystalline

Spray Chemical Vapor Deposition of Single-Source Precursors for Chalcopyrite I-III-VI2 Thin-Film Materials

Science.gov (United States)

Hepp, Aloysius F.; Banger, Kulbinder K.; Jin, Michael H.-C.; Harris, Jerry D.; McNatt, Jeremiah S.; Dickman, John E.

2008-01-01

Thin-film solar cells on flexible, lightweight, space-qualified substrates provide an attractive approach to fabricating solar arrays with high mass-specific power. A polycrystalline chalcopyrite absorber layer is among the new generation of photovoltaic device technologies for thin film solar cells. At NASA Glenn Research Center we have focused on the development of new single-source precursors (SSPs) for deposition of semiconducting chalcopyrite materials onto lightweight, flexible substrates. We describe the syntheses and thermal modulation of SSPs via molecular engineering. Copper indium disulfide and related thin-film materials were deposited via aerosol-assisted chemical vapor deposition using SSPs. Processing and post-processing parameters were varied in order to modify morphology, stoichiometry, crystallography, electrical properties, and optical properties to optimize device quality. Growth at atmospheric pressure in a horizontal hotwall reactor at 395 C yielded the best device films. Placing the susceptor closer to the evaporation zone and flowing a more precursor-rich carrier gas through the reactor yielded shinier-, smoother-, and denser-looking films. Growth of (112)-oriented films yielded more Cu-rich films with fewer secondary phases than growth of (204)/(220)-oriented films. Post-deposition sulfur-vapor annealing enhanced stoichiometry and crystallinity of the films. Photoluminescence studies revealed four major emission bands and a broad band associated with deep defects. The highest device efficiency for an aerosol-assisted chemical vapor deposited cell was one percent.

Polycrystalline silicon thin-film solar cells on glass

Energy Technology Data Exchange (ETDEWEB)

Gall, S.; Becker, C.; Conrad, E.; Dogan, P.; Fenske, F.; Gorka, B.; Lee, K.Y.; Rau, B.; Ruske, F.; Rech, B. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH (formerly Hahn-Meitner-Institut Berlin GmbH), Department Silicon Photovoltaics (SE1), Kekulestr. 5, D-12489 Berlin (Germany)

2009-06-15

Poly-Si thin-film solar cells on glass feature the potential to reach single-junction efficiencies of 15% or even higher at low costs. In this paper innovative approaches are discussed, which could lead to substantial efficiency improvements and significant cost reductions: (i) preparation of large-grained poly-Si films using the 'seed layer concept' targeting at high material quality, (ii) utilization of ZnO:Al-coated glass enabling simple contacting and light-trapping schemes, (iii) utilization of high-rate electron-beam evaporation for the absorber deposition offering a high potential for cost reduction. (author)

Significant efficiency enhancement in thin film solar cells using laser beam-induced graphene transparent conductive electrodes

OpenAIRE

Thekkekara, L. V.; Cai, Bouyan

2018-01-01

Thin film solar cells have been attractive for decades in advanced green technology platforms due to its possibilities to be integrated with buildings and on-chip applications. However, the bottleneck issues involved to consider the current solar cells as a major electricity source includes the lower efficiencies and cost-effectiveness. We numerically demonstrate the concept of the absorption enhancement in thin-film amorphous silicon solar cells using the laser beam-induced graphene material...

Transparent conductive zinc oxide basics and applications in thin film solar cells

CERN Document Server

Klein, Andreas; Rech, Bernd

2008-01-01

Zinc oxide (ZnO) belongs to the class of transparent conducting oxides which can be used as transparent electrodes in electronic devices or heated windows. In this book the material properties of, the deposition technologies for, and applications of zinc oxide in thin film solar cells are described in a comprehensive manner. Structural, morphological, optical and electronic properties of ZnO are treated in this review. The editors and authors of this book are specialists in deposition, analysis and fabrication of thin-film solar cells and especially of ZnO. This book is intended as an overview and a data collection for students, engineers and scientist.

Materials and Light Management for High-Efficiency Thin-Film Silicon Solar Cells

OpenAIRE

Tan, H.

2015-01-01

Direct conversion of sunlight into electricity is one of the most promising approaches to provide sufficient renewable energy for humankind. Solar cells are such devices which can efficiently generate electricity from sunlight through the photovoltaic effect. Thin-film silicon solar cells, a type of photovoltaic (PV) devices which deploy the chemical-vapor-deposited hydrogenated amorphous silicon (a-Si:H) and nanocrystalline silicon (nc-Si:H) and their alloys as the absorber layers and doped ...

Sputter Deposited TiOx Thin-Films as Electron Transport Layers in Organic Solar Cells

DEFF Research Database (Denmark)

Mirsafaei, Mina; Bomholt Jensen, Pia; Lakhotiya, Harish

transparency and favorable energy-level alignment with many commonly used electron-acceptor materials. There are several methods available for fabricating compact TiOx thin-films for use in organic solar cells, including sol-gel solution processing, spray pyrolysis and atomic-layer deposition; however...... of around 7%, by incorporating sputter deposited TiOx thin-films as electron-transport and exciton-blocking layers. In the work, we report on the effect of different TiOx deposition temperatures and thicknesses on the organic-solar-cell device performance. Besides optical characterization, AFM and XRD...... analyses are performed to characterize the morphology and crystal structure of the films, and external quantum efficiency measurements are employed to shed further light on the device performance. Our study presents a novel method for implementation of TiOx thin-films as electron-transport layer in organic...

Ferroelectric thin films using oxides as raw materials

Directory of Open Access Journals (Sweden)

E.B. Araújo

1999-01-01

Full Text Available This work describes an alternative method for the preparation of ferroelectric thin films based on pre-calcination of oxides, to be used as precursor material for a solution preparation. In order to show the viability of the proposed method, PbZr0.53Ti0.47O3 and Bi4Ti3O12 thin films were prepared on fused quartz and Si substrates. The results were analyzed by X-ray Diffraction (XRD, Scanning Electron Microscopy (SEM, Infrared Spectroscopy (IR and Rutherford Backscattering Spectroscopy (RBS. The films obtained show good quality, homogeneity and the desired stoichiometry. The estimated thickness for one layer deposition was approximately 1000 Å and 1500 Å for Bi4Ti3O12 and PbZr0.53Ti0.47O3 films, respectively.

Large Area Thin Film Silicon: Synergy between Displays and Solar Cells

NARCIS (Netherlands)

Schropp, R.E.I.

2012-01-01

Thin-film silicon technology has changed our society, owing to the rapid advance of its two major application fields in communication (thin-film displays) and sustainable energy (thin-film solar cells). Throughout its development, advances in these application fields have always benefitted each

Chemical bath deposition of thin semiconductor films for use as buffer layers in CuInS2 thin film solar cells

International Nuclear Information System (INIS)

Kaufmann, C.A.

2002-01-01

A CulnS 2 thin film solar cell is a multilayered semiconductor device. The solar cells discussed have a layer sequence Mo/CulnS 2 /buffer/i-ZnO/ZnO:Ga, where a heterojunction establishes between the p-type absorber and the n-type front contact. Conventionally the buffer consists of CdS, deposited by chemical bath deposition (CBD). Apart from providing process oriented benefits the buffer layer functions as a tool for engineering the energy band line-up at the heterojunction interface. Motivated through environmental concern and EU legislation it is felt necessary to substitute this potentially toxic layer by an alternative, Cd-free component. This thesis investigates the suitability of various Zn- and In-compounds, in particular In(OH,O) x S y , as alternative buffer layer materials using CBD. Initial experiments were carried out depositing Zn-based compounds from aqueous solutions. Characterization of the layers, the solution and the processed solar cells was performed. This thesis focuses on the investigation of the CBD process chemistry for the deposition of In-compound thin films. A careful study of the morphology and composition of the deposited thin films was conducted using electron microscopy (SEM, HREM), elastic recoil detection analysis, X-ray photoelectron spectroscopy and optical transmission spectroscopy. This allowed conclusions concerning the nucleation and film growth mechanism from the chemical bath. Connections between bath chemistry, different growth phases, layer morphology and solar cell performance were sought and an improved deposition process was developed. As a result, Cd-free CulnS 2 thin film solar cells with efficiencies of up to 10.6%) (total area) could be produced. Overall the substitution of CdS is shown to be possible by different alternative compounds, such as Zn(OH,O) x S y or In(OH,O) x S y . In the case of In(OH,O) x S y , an understanding of the CBD process and the effect of different growth phases on the resulting solar cell

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.

P-doped strontium titanate grown using two target pulsed laser deposition for thin film solar cells

Science.gov (United States)

Man, Hamdi

Thin-film solar cells made of Mg-doped SrTiO3 p-type absorbers are promising candidates for clean energy generation. This material shows p-type conductivity and also demonstrates reasonable absorption of light. In addition, p-type SrTiO3 can be deposited as thin films so that the cost can be lower than the competing methods. In this work, Mg-doped SrTiO3 (STO) thin-films were synthesized and analyzed in order to observe their potential to be employed as the base semiconductor in photovoltaic applications. Mg-doped STO thin-films were grown by using pulsed laser deposition (PLD) using a frequency quadrupled Yttrium Aluminum Garnet (YAG) laser and with a substrate that was heated by back surface absorption of infrared (IR) laser light. The samples were characterized using X-ray photoelectron spectroscopy (XPS) and it was observed that Mg atoms were doped successfully in the stoichiometry. Reflection high energy electron diffraction (RHEED) spectroscopy proved that the thin films were polycrystalline. Kelvin Probe work function measurements indicated that the work function of the films were 4.167 eV after annealing. UV/Vis Reflection spectroscopy showed that Mg-doped STO thin-films do not reflect significantly except in the ultraviolet region of the spectrum where the reflection percentage increased up to 80%. Self-doped STO thin-films, Indium Tin Oxide (ITO) thin films and stainless steel foil (SSF) were studied in order to observe their characteristics before employing them in Mg-doped STO based solar cells. Self-doped STO thin films were grown using PLD and the results showed that they are capable of serving as the n-type semiconductor in solar cell applications with oxygen vacancies in their structure and low reflectivity. Indium Tin Oxide thin-films grown by PLD system showed low 25-50 ?/square sheet resistance and very low reflection features. Finally, commercially available stainless steel foil substrates were excellent substrates for the inexpensive growth of

Cuinse2 Thin Film For Solar Cell By Flash Evaporation

OpenAIRE

A.H. Soepardjo

2009-01-01

Deposition of thin films for material solar cell CuInSe2 are relatively simple. In this research mainly focused on the use of flash evaporation method, and the material created can then be characterized by optical and electrical properties. The optical characterization is done by X-ray Diffraction (XRD), Energy Dispersive Spectroscopy (EDS), and transmission and reflection by UV-VIS spectrophotometry. Electrical characterization is done by utilizing the Hall effect equipment. From these chara...

Hybrid thin films based on bilayer heterojunction of titania nanocrystals/polypyrrole/natural dyes (Kappaphycus alvarezii) materials

Science.gov (United States)

Ghazali, Salmah Mohd; Salleh, Hasiah; Dagang, Ahmad Nazri; Ghazali, Mohd Sabri Mohd; Ali, Nik Aziz Nik; Rashid, Norlaily Abdul; Kamarulzaman, Nurul Huda; Ahmad, Wan Almaz Dhafina Che Wan

2017-09-01

In this research, hybrid thin films which consist of a combination of organic red seaweed (RS) (Kappaphycus alvarezii) and polypyrrole (PPy) with inorganic titania nanocrystals (TiO2 NCs) materials were fabricated. These hybrid thin films were fabricated accordingly with bilayer heterojunction of ITO/TiO2 NCs/PPy/RS via electrochemical method using Electrochemical Impedance Spectroscopy (EIS). The effect of number of scans (thickness) of titania on optical and electrical properties of hybrid thin films were studied. TiO2 NCs function as an electron acceptor and electronic conductor. Meanwhile, PPy acts as holes conductor and RS dye acts as a photosensitizer enhances the optical and electrical properties of the thin films. The UV absorption spectrum of TiO2 NCs, PPy and RS are characterized by UV-Visible spectroscopy, while the functional group of RS was characterized by Fourier transform infrared spectroscopy (FTIR). The UV-Vis spectra showed that TiO2 NCs, PPy and RS were absorbed over a wide range of light spectrum which were 200-300 nm, 300-900 nm and 250-900 nm; respectively. The FTIR spectra of the RS showed the presence of hydroxyl group which was responsible for a good sensitizer for these hybrid solar cells. The electrical conductivity of these hybrid thin films were measured by using four point probes. The electrical conductivity of ITO/ (1)TiO2 NCs/PPy/RS thin film under the radiation of 100 Wm-2 was 0.062 Scm-1, hence this hybrid thin films can be applied in solar cell application.

Thin film microelectrodes for electrochemical detection of neurotransmitters

DEFF Research Database (Denmark)

Larsen, Simon Tylsgaard

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

Thin film preparation of semiconducting iron pyrite

Science.gov (United States)

Smestad, Greg P.; Ennaoui, Ahmed; Fiechter, Sebastian; Hofmann, Wolfgang; Tributsch, Helmut; Kautek, Wolfgang

1990-08-01

Pyrite (Fe52) has been investigated as a promising new absorber material for thin film solar cell applications because of its high optical absorption coefficient of 1OL cm1, and its bandgap of 0.9 to 1.0 eV. Thin layers have been prepared by Metal Organic Chemical Vapor Deposition, MOCVD, Chemical Spray Pyrolysis, CSP, Chemical Vapor Transport, CVT, and Sulfurization of Iron Oxide films, 510. It is postulated that for the material FeS2, if x is not zero, a high point defect concentration results from replacing 2 dipoles by single S atoms. This causes the observed photovoltages and solar conversion efficiencies to be lower than expected. Using the Fe-O-S ternary phase diagram and the related activity plots, a thermodynamic understanding is formulated for the resulting composition of each of these types of films. It is found that by operating in the oxide portion of the phase diagram, the resulting oxidation state favors pyrite formation over FeS. By proper orientation of the grains relative to the film surface, and by control of pinholes and stoichiometry, an efficient thin film photovolatic solar cell material could be achieved.

Method for producing textured substrates for thin-film photovoltaic cells

Science.gov (United States)

Lauf, Robert J.

1994-01-01

The invention pertains to the production of ceramic substrates used in the manufacture of thin-film photovoltaic cells used for directly converting solar energy to electrical energy. Elongated ribbon-like sheets of substrate precursor containing a mixture of ceramic particulates, a binder, and a plasticizer are formed and then while green provided with a mechanically textured surface region used for supporting the thin film semiconductor of the photovoltaic cell when the sheets of the substrate precursor are subsequently cut into substrate-sized shapes and then sintered. The textured surface pattern on the substrate provides enhanced light trapping and collection for substantially increasing the solar energy conversion efficiency of thin-film photovoltaic cells.

Steps Towards Industrialization of Cu-III-VI2Thin-Film Solar Cells:Linking Materials/Device Designs to Process Design For Non-stoichiometric Photovoltaic Materials.

Science.gov (United States)

Hwang, Huey-Liang; Chang, Hsueh-Hsin; Sharma, Poonam; Letha, Arya Jagadhamma; Shao, Lexi; Zhang, Yafei; Tseng, Bae-Heng

2016-10-01

The concept of in-line sputtering and selenization become industrial standard for Cu-III-VI 2 solar cell fabrication, but still it's very difficult to control and predict the optical and electrical parameters, which are closely related to the chemical composition distribution of the thin film. The present review article addresses onto the material design, device design and process design using parameters closely related to the chemical compositions. Its variation leads to change in the Poisson equation, current equation, and continuity equation governing the device design. To make the device design much realistic and meaningful, we need to build a model that relates the opto-electrical properties to the chemical composition. The material parameters as well as device structural parameters are loaded into the process simulation to give a complete set of process control parameters. The neutral defect concentrations of non-stoichiometric CuMSe 2 (M = In and Ga) have been calculated under the specific atomic chemical potential conditions using this methodology. The optical and electrical properties have also been investigated for the development of a full-function analytical solar cell simulator. The future prospects regarding the development of copper-indium-gallium-selenide thin film solar cells have also been discussed.

High index glass thin film processing for photonics and photovoltaic (PV) applications

Science.gov (United States)

Ogbuu, Okechukwu Anthony

To favorably compete with fossil-fuel technology, the greatest challenge for thin film solar-cells is to improve efficiency and reduce material cost. Thickness scaling to thin film reduces material cost but affects the light absorption in the cells; therefore a concept that traps incident photons and increases its optical path length is needed to boost absorption in thin film solar cells. One approach is the integration of low symmetric gratings (LSG), using high index material, on either the front-side or backside of 30 um thin c-Si cells. In this study, Multicomponent TeO2--Bi2O 3--ZnO (TBZ) glass thin films were prepared using RF magnetron sputtering under different oxygen flow rates. The influences of oxygen flow rate on the structural and optical properties of the resulting thin films were investigated. The structural origin of the optical property variation was studied using X-ray diffraction, X-ray photoelectron spectroscopy, Raman Spectroscopy, and transmission electron microscopy. The results indicate that TBZ glass thin film is a suitable material for front side LSG material photovoltaic and photonics applications due to their amorphous nature, high refractive index (n > 2), broad band optical transparency window, low processing temperature. We developed a simple maskless method to pattern sputtered tellurite based glass thin films using unconventional agarose hydrogel mediated wet etching. Conventional wet etching process, while claiming low cost and high throughput, suffers from reproducibility and pattern fidelity issues due to the isotropic nature of wet chemical etching when applied to glasses and polymers. This method overcomes these challenges by using an agarose hydrogel stamp to mediate a conformal etching process. In our maskless method, agarose hydrogel stamps are patterned following a standard soft lithography and replica molding process from micropatterned masters and soaked in a chemical etchant. The micro-scale features on the stamp are

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.

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.

Microcrystalline silicon carbide alloys prepared with HWCVD as highly transparent and conductive window layers for thin film solar cells

International Nuclear Information System (INIS)

Finger, F.; Astakhov, O.; Bronger, T.; Carius, R.; Chen, T.; Dasgupta, A.; Gordijn, A.; Houben, L.; Huang, Y.; Klein, S.; Luysberg, M.; Wang, H.; Xiao, L.

2009-01-01

Crystalline silicon carbide alloys have a very high potential as transparent conductive window layers in thin-film solar cells provided they can be prepared in thin-film form and at compatible deposition temperatures. The low-temperature deposition of such material in microcrystalline form (μc-Si:C:H) was realized by use of monomethylsilane precursor gas diluted in hydrogen with the Hot-Wire Chemical Vapor Deposition process. A wide range of deposition parameters has been investigated and the structural, electronic and optical properties of the μc-SiC:H thin films have been studied. The material, which is strongly n-type from unintentional doping, has been used as window layer in n-side illuminated microcrystalline silicon solar cells. High short-circuit current densities are obtained due to the high transparency of the material resulting in a maximum solar cell conversion efficiency of 9.2%.

Extremely Efficient Design of Organic Thin Film Solar Cells via Learning-Based Optimization

Directory of Open Access Journals (Sweden)

Mine Kaya

2017-11-01

Full Text Available Design of efficient thin film photovoltaic (PV cells require optical power absorption to be computed inside a nano-scale structure of photovoltaics, dielectric and plasmonic materials. Calculating power absorption requires Maxwell’s electromagnetic equations which are solved using numerical methods, such as finite difference time domain (FDTD. The computational cost of thin film PV cell design and optimization is therefore cumbersome, due to successive FDTD simulations. This cost can be reduced using a surrogate-based optimization procedure. In this study, we deploy neural networks (NNs to model optical absorption in organic PV structures. We use the corresponding surrogate-based optimization procedure to maximize light trapping inside thin film organic cells infused with metallic particles. Metallic particles are known to induce plasmonic effects at the metal–semiconductor interface, thus increasing absorption. However, a rigorous design procedure is required to achieve the best performance within known design guidelines. As a result of using NNs to model thin film solar absorption, the required time to complete optimization is decreased by more than five times. The obtained NN model is found to be very reliable. The optimization procedure results in absorption enhancement greater than 200%. Furthermore, we demonstrate that once a reliable surrogate model such as the developed NN is available, it can be used for alternative analyses on the proposed design, such as uncertainty analysis (e.g., fabrication error.

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

Surface, interface and thin film characterization of nano-materials using synchrotron radiation

International Nuclear Information System (INIS)

Kimura, Shigeru; Kobayashi, Keisuke

2005-01-01

From the results of studies in the nanotechnology support project of the Ministry of Education, Culture, Sports, Science and Technology of Japan, several investigations on the surface, interface and thin film characterization of nano-materials are described; (1) the MgB 2 thin film by X-ray diffraction, (2) the magnetism of the Pt thin film on a Co film by X-ray magnetic circular dichroism measurement, (3) the structure and physical properties of oxygen molecules absorbed in a micro hole of the cheleted polymer crystal by the direct observation in X-ray powder diffraction, and (4) the thin film gate insulator with a large dielectric constant, thermally treated HfO 2 /SiO 2 /Si, by X-ray photoelectron spectroscopy. (M.H.)

Disorder improves nanophotonic light trapping in thin-film solar cells

Energy Technology Data Exchange (ETDEWEB)

Paetzold, U. W., E-mail: u.paetzold@fz-juelich.de; Smeets, M.; Meier, M.; Bittkau, K.; Merdzhanova, T.; Smirnov, V.; Carius, R.; Rau, U. [IEK5—Photovoltaik, Forschungszentrum Jülich GmbH, 52425 Jülich (Germany); Michaelis, D.; Waechter, C. [Fraunhofer Institut für Angewandte Optik und Feinmechanik, Albert Einstein Str. 7, D-07745 Jena (Germany)

2014-03-31

We present a systematic experimental study on the impact of disorder in advanced nanophotonic light-trapping concepts of thin-film solar cells. Thin-film solar cells made of hydrogenated amorphous silicon were prepared on imprint-textured glass superstrates. For periodically textured superstrates of periods below 500 nm, the nanophotonic light-trapping effect is already superior to state-of-the-art randomly textured front contacts. The nanophotonic light-trapping effect can be associated to light coupling to leaky waveguide modes causing resonances in the external quantum efficiency of only a few nanometer widths for wavelengths longer than 500 nm. With increasing disorder of the nanotextured front contact, these resonances broaden and their relative altitude decreases. Moreover, overall the external quantum efficiency, i.e., the light-trapping effect, increases incrementally with increasing disorder. Thereby, our study is a systematic experimental proof that disorder is conceptually an advantage for nanophotonic light-trapping concepts employing grating couplers in thin-film solar cells. The result is relevant for the large field of research on nanophotonic light trapping in thin-film solar cells which currently investigates and prototypes a number of new concepts including disordered periodic and quasi periodic textures.

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.

Numerical Optimization of a Bifacial Bi-Glass Thin-Film a-Si:H Solar Cell for Higher Conversion Efficiency

Science.gov (United States)

Berrian, Djaber; Fathi, Mohamed; Kechouane, Mohamed

2018-02-01

Bifacial solar cells that maximize the energy output per a square meter have become a new fashion in the field of photovoltaic cells. However, the application of thin-film material on bifacial solar cells, viz., thin-film amorphous hydrogenated silicon ( a- Si:H), is extremely rare. Therefore, this paper presents the optimization and influence of the band gap, thickness and doping on the performance of a glass/glass thin-film a- Si:H ( n- i- p) bifacial solar cell, using a computer-aided simulation tool, Automat for simulation of hetero-structures (AFORS-HET). It is worth mentioning that the thickness and the band gap of the i-layer are the key parameters in achieving higher efficiency and hence it has to be handled carefully during the fabrication process. Furthermore, an efficient thin-film a- Si:H bifacial solar cell requires thinner and heavily doped n and p emitter layers. On the other hand, the band gap of the p-layer showed a dramatic reduction of the efficiency at 2.3 eV. Moreover, a high bifaciality factor of more than 92% is attained, and top efficiency of 10.9% is revealed under p side illumination. These optimizations demonstrate significant enhancements of the recent experimental work on thin-film a- Si:H bifacial solar cells and would also be useful for future experimental investigations on an efficient a- Si:H thin-film bifacial solar cell.

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

Crystal structure determination of solar cell materials: Cu2ZnSnS4 thin films using X-ray anomalous dispersion

International Nuclear Information System (INIS)

Nozaki, Hiroshi; Fukano, Tatsuo; Ohta, Shingo; Seno, Yoshiki; Katagiri, Hironori; Jimbo, Kazuo

2012-01-01

Highlights: ► Cu 2 ZnSnS 4 thin films as a solar cell material were synthesized. ► The wavelength dependences of the diffraction intensity were measured. ► The crystal structures were clearly identified as kesterite structure for all samples. ► Crystal structure analysis revealed that the atomic compositions were Cu/(Zn + Sn) = 0.97 and Zn/Sn = 1.42 for the sample synthesized using stoichiometric amount of starting materials. - Abstract: The crystal structure of Cu 2 ZnSnS 4 (CZTS) thin films fabricated by vapor-phase sulfurization was determined using X-ray anomalous dispersion. High statistic synchrotron radiation X-ray diffraction data were collected from very small amounts of powder. By analyzing the wavelength dependencies of the diffraction peak intensities, the crystal structure was clearly identified as kesterite. Rietveld analysis revealed that the atomic composition deviated from stoichiometric composition, and the compositions were Cu/(Zn + Sn) = 0.97, and Zn/Sn = 1.42.

High-rate deposition of epitaxial layers for efficient low-temperature thin film epitaxial silicon solar cells

Energy Technology Data Exchange (ETDEWEB)

Oberbeck, L.; Schmidt, J.; Wagner, T.A.; Bergmann, R.B. [Stuttgart Univ. (Germany). Inst. of Physical Electronics

2001-07-01

Low-temperature deposition of Si for thin-film solar cells has previously been hampered by low deposition rates and low material quality, usually reflected by a low open-circuit voltage of these solar cells. In contrast, ion-assisted deposition produces Si films with a minority-carrier diffusion length of 40 {mu}m, obtained at a record deposition rate of 0.8 {mu}m/min and a deposition temperature of 650{sup o}C with a prebake at 810{sup o}C. A thin-film Si solar cell with a 20-{mu}m-thick epitaxial layer achieves an open-circuit voltage of 622 mV and a conversion efficiency of 12.7% without any light trapping structures and without high-temperature solar cell process steps. (author)

Proposed suitable electron reflector layer materials for thin-film CuIn1-xGaxSe2 solar cells

Science.gov (United States)

Sharbati, Samaneh; Gharibshahian, Iman; Orouji, Ali A.

2018-01-01

This paper investigates the electrical properties of electron reflector layer to survey materials as an electron reflector (ER) for chalcopyrite CuInGaSe solar cells. The purpose is optimizing the conduction-band and valence-band offsets at ER layer/CIGS junction that can effectively reduce the electron recombination near the back contact. In this work, an initial device model based on an experimental solar cell is established, then the properties of a solar cell with electron reflector layer are physically analyzed. The electron reflector layer numerically applied to baseline model of thin-film CIGS cell fabricated by ZSW (efficiency = 20.3%). The improvement of efficiency is achievable by electron reflector layer materials with Eg > 1.3 eV and -0.3 AsS4 as well as CuIn1-xGaxSe (x > 0.5) are efficient electron reflector layer materials, so the potential improvement in efficiency obtained relative gain of 5%.

Automatic identification of single- and/or few-layer thin-film material

DEFF Research Database (Denmark)

2014-01-01

One or more digital representations of single- (101) and/or few-layer (102) thin- film material are automatically identified robustly and reliably in a digital image (100), the digital image (100) having a predetermined number of colour components, by - determining (304) a background colour...... component of the digital image (100) for each colour component, and - determining or estimating (306) a colour component of thin-film material to be identified in the digital image (100) for each colour component by obtaining a pre-determined contrast value (C R; C G; C B) for each colour component...

Magnetic hysteresis measurements of thin films under isotropic stress.

Science.gov (United States)

Holland, Patrick; Dubey, Archana; Geerts, Wilhelmus

2000-10-01

Nowadays, ferromagnetic thin films are widely applied in devices for information technology (credit cards, video recorder tapes, floppies, hard disks) and sensors (air bags, anti-breaking systems, navigation systems). Thus, with the increase in the use of magnetic media continued investigation of magnetic properties of materials is necessary to help in determining the useful properties of materials for new or improved applications. We are currently interested in studying the effect of applied external stress on Kerr hysteresis curves of thin magnetic films. The Ni and NiFe films were grown using DC magnetron sputtering with Ar as the sputter gas (pAr=4 mTorr; Tsub=55-190 C). Seed and cap layers of Ti were used on all films for adhesion and oxidation protection, respectively. A brass membrane pressure cell was designed to apply in-plane isotropic stress to thin films. In this pressure cell, gas pressure is used to deform a flexible substrate onto which a thin magnetic film has been sputtered. The curvature of the samples could be controlled by changing the gas pressure to the cell. Magneto-Optical in-plane hysteresis curves at different values of strain were measured. The results obtained show that the stress sensitivity is dependent on the film thickness. For the 500nm NiFe films, the coercivity strongly decreased as a function of the applied stress.

Dielectric Scattering Patterns for Efficient Light Trapping in Thin-Film Solar Cells.

Science.gov (United States)

van Lare, Claire; Lenzmann, Frank; Verschuuren, Marc A; Polman, Albert

2015-08-12

We demonstrate an effective light trapping geometry for thin-film solar cells that is composed of dielectric light scattering nanocavities at the interface between the metal back contact and the semiconductor absorber layer. The geometry is based on resonant Mie scattering. It avoids the Ohmic losses found in metallic (plasmonic) nanopatterns, and the dielectric scatterers are well compatible with nearly all types of thin-film solar cells, including cells produced using high temperature processes. The external quantum efficiency of thin-film a-Si:H solar cells grown on top of a nanopatterned Al-doped ZnO, made using soft imprint lithography, is strongly enhanced in the 550-800 nm spectral band by the dielectric nanoscatterers. Numerical simulations are in good agreement with experimental data and show that resonant light scattering from both the AZO nanostructures and the embedded Si nanostructures are important. The results are generic and can be applied on nearly all thin-film solar cells.

Organic-inorganic hybrid materials as semiconducting channels in thin-film field-effect transistors

Science.gov (United States)

Kagan; Mitzi; Dimitrakopoulos

1999-10-29

Organic-inorganic hybrid materials promise both the superior carrier mobility of inorganic semiconductors and the processability of organic materials. A thin-film field-effect transistor having an organic-inorganic hybrid material as the semiconducting channel was demonstrated. Hybrids based on the perovskite structure crystallize from solution to form oriented molecular-scale composites of alternating organic and inorganic sheets. Spin-coated thin films of the semiconducting perovskite (C(6)H(5)C(2)H(4)NH(3))(2)SnI(4) form the conducting channel, with field-effect mobilities of 0.6 square centimeters per volt-second and current modulation greater than 10(4). Molecular engineering of the organic and inorganic components of the hybrids is expected to further improve device performance for low-cost thin-film transistors.

Vanadium nitride as a novel thin film anode material for rechargeable lithium batteries

International Nuclear Information System (INIS)

Sun Qian; Fu Zhengwen

2008-01-01

Vanadium mononitride (VN) thin films have been successfully fabricated by magnetron sputtering. Its electrochemical behaviour with lithium was examined by galvanostatic cell cycling and cyclic voltammetry. The capacity of VN was found to be stable above 800 mAh g -1 after 50 cycles. By using ex situ X-ray diffraction, high-resolution transmission electron microscopy and selected area electron diffraction as well as in situ spectroelectrochemical measurements, the electrochemical reaction mechanism of VN with lithium was investigated. The reversible conversion reaction of VN into metal V and Li 3 N was revealed. The high reversible capacity and good stable cycle of VN thin film electrode made it a new promising lithium-ion storage material for future rechargeable lithium batteries

Analysis of Electrical Characteristics of Thin Film Photovoltaic Cells

Science.gov (United States)

Kasick, Michael P.

2004-01-01

Solar energy is the most abundant form of energy in many terrestrial and extraterrestrial environments. Often in extraterrestrial environments sunlight is the only readily available form of energy. Thus the ability to efficiently harness solar energy is one of the ultimate goals in the design of space power systems. The essential component that converts solar energy into electrical energy in a solar energy based power system is the photovoltaic cell. Traditionally, photovoltaic cells are based on a single crystal silicon absorber. While silicon is a well understood technology and yields high efficiency, there are inherent disadvantages to using single crystal materials. The requirements of weight, large planar surfaces, and high manufacturing costs make large silicon cells prohibitively expensive for use in certain applications. Because of silicon s disadvantages, there is considerable ongoing research into alternative photovoltaic technologies. In particular, thin film photovoltaic technologies exhibit a promising future in space power systems. While they are less mature than silicon, the better radiation hardness, reduced weight, ease of manufacturing, low material cost, and the ability to use virtually any exposed surface as a substrate makes thin film technologies very attractive for space applications. The research group lead by Dr. Hepp has spent several years researching copper indium disulfide as an absorber material for use in thin film photovoltaic cells. While the group has succeeded in developing a single source precursor for CuInS2 as well as a unique method of aerosol assisted chemical vapor deposition, the resulting cells have not achieved adequate efficiencies. While efficiencies of 11 % have been demonstrated with CuInS2 based cells, the cells produced by this group have shown efficiencies of approximately 1 %. Thus, current research efforts are turning towards the analysis of the individual layers of these cells, as well as the junctions between

Preparation of Cu{sub 2}ZnSnS{sub 4} thin films by sulfurizing stacked precursor thin films via successive ionic layer adsorption and reaction method

Energy Technology Data Exchange (ETDEWEB)

Su Zhenghua; Yan Chang; Sun Kaiwen; Han Zili [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); Liu Fangyang, E-mail: liufangyang@csu.edu.cn [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); Liu Jin [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); Lai Yanqing, E-mail: laiyanqingcsu@163.com [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); Li Jie; Liu Yexiang [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China)

2012-07-15

Earth-abundant Cu{sub 2}ZnSnS{sub 4} is a promising alternative photovoltaic material which has been examined as absorber layer of thin film solar cells. In this study, Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films have been successfully fabricated by sulfurizing stacked precursor thin films via successive ionic layer adsorption and reaction (SILAR) method. The prepared CZTS thin films have been characterized by X-ray diffraction, energy dispersive spectrometer, Raman spectroscopy, UV-vis spectroscopy, Hall effect measurements and photoelectrochemical tests. Results reveal that the thin films have kesterite structured Cu{sub 2}ZnSnS{sub 4} and the p-type conductivity with a carrier concentration in the order of 10{sup 18} cm{sup -3} and an optical band gap of 1.5 eV, which are suitable for applications in thin film solar cells.

Indium sulfide thin films as window layer in chemically deposited solar cells

Energy Technology Data Exchange (ETDEWEB)

Lugo-Loredo, S. [Universidad Autónoma de Nuevo León, UANL, Fac. de Ciencias Químicas, Av. Universidad S/N Ciudad Universitaria San Nicolás de Los Garza Nuevo León, C.P. 66451 (Mexico); Peña-Méndez, Y., E-mail: yolapm@gmail.com [Universidad Autónoma de Nuevo León, UANL, Fac. de Ciencias Químicas, Av. Universidad S/N Ciudad Universitaria San Nicolás de Los Garza Nuevo León, C.P. 66451 (Mexico); Calixto-Rodriguez, M. [Universidad Tecnológica Emiliano Zapata del Estado de Morelos, Av. Universidad Tecnológica No. 1, C.P. 62760 Emiliano Zapata, Morelos (Mexico); Messina-Fernández, S. [Universidad Autónoma de Nayarit, Ciudad de la Cultura “Amado Nervo” S/N, C.P. 63190 Tepic, Nayarit (Mexico); Alvarez-Gallegos, A. [Universidad Autónoma del Estado de Morelos, Centro de Investigación en Ingeniería y Ciencias Aplicadas, Av. Universidad 1001, C.P. 62209, Cuernavaca Morelos (Mexico); Vázquez-Dimas, A.; Hernández-García, T. [Universidad Autónoma de Nuevo León, UANL, Fac. de Ciencias Químicas, Av. Universidad S/N Ciudad Universitaria San Nicolás de Los Garza Nuevo León, C.P. 66451 (Mexico)

2014-01-01

Indium sulfide (In{sub 2}S{sub 3}) thin films have been synthesized by chemical bath deposition technique onto glass substrates using In(NO{sub 3}){sub 3} as indium precursor and thioacetamide as sulfur source. X-ray diffraction studies have shown that the crystalline state of the as-prepared and the annealed films is β-In{sub 2}S{sub 3}. Optical band gap values between 2.27 and 2.41 eV were obtained for these films. The In{sub 2}S{sub 3} thin films are photosensitive with an electrical conductivity value in the range of 10{sup −3}–10{sup −7} (Ω cm){sup −1}, depending on the film preparation conditions. We have demonstrated that the In{sub 2}S{sub 3} thin films obtained in this work are suitable candidates to be used as window layer in thin film solar cells. These films were integrated in SnO{sub 2}:F/In{sub 2}S{sub 3}/Sb{sub 2}S{sub 3}/PbS/C–Ag solar cell structures, which showed an open circuit voltage of 630 mV and a short circuit current density of 0.6 mA/cm{sup 2}. - Highlights: • In{sub 2}S{sub 3} thin films were deposited using the Chemical Bath Deposition technique. • A direct energy band gap between 2.41 to 2.27 eV was evaluated for the In{sub 2}S{sub 3} films. • We made chemically deposited solar cells using the In{sub 2}S{sub 3} thin films.

Thin film solar cells: research in an industrial perspective.

Science.gov (United States)

Edoff, Marika

2012-01-01

Electricity generation by photovoltaic conversion of sunlight is a technology in strong growth. The thin film technology is taking market share from the dominant silicon wafer technology. In this article, the market for photovoltaics is reviewed, the concept of photovoltaic solar energy conversion is discussed and more details are given about the present technological limitations of thin film solar cell technology. Special emphasis is given for solar cells which employ Cu(In,Ga)Se(2) and Cu(2)ZnSn(S,Se)(4) as the sunlight-absorbing layer.

High efficiency thin-film solar cells for space applications: challenges and opportunities

NARCIS (Netherlands)

Leest, R.H. van

2017-01-01

In theory high efficiency thin-film III-V solar cells obtained by the epitaxial lift-off (ELO) technique offer excellent characteristics for application in space solar panels. The thesis describes several studies that investigate the space compatibility of the thin-film solar cell design developed

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.

Band alignment measurements at heterojunction interfaces in layered thin film solar cells & thermoelectrics

Science.gov (United States)

Fang, Fang

2011-12-01

Public awareness of the increasing energy crisis and the related serious environmental concerns has led to a significantly growing demand for alternative clean and renewable energy resources. Thin film are widely applied in multiple renewable energy devices owing to the reduced amount of raw materials and increase flexibility of choosing from low-cost candidates, which translates directly into reduced capital cost. This is a key driving force to make renewable technology competitive in the energy market. This thesis is focused on the measurement of energy level alignments at interfaces of thin film structures for renewable energy applications. There are two primary foci: II -VI semiconductor ZnSe/ZnTe thin film solar cells and Bi2Te3/Sb2Te3 thin film structures for thermoelectric applications. In both cases, the electronic structure and energy band alignment at interfaces usually controls the carrier transport behavior and determines the quality of the device. High-resolution photoemission spectroscopy (lab-based XPS & synchrotron-based UPS) was used to investigate the chemical and electronic properties of epitaxial Bi2Te3 and Sb2Te3 thin films, in order to validate the anticipated band alignment at interfaces in Bi 2Te3/Sb2Te3 superlattices as one favoring electron-transmission. A simple, thorough two-step treatment of a chemical etching in dilute hydrochloric acid solution and a subsequent annealing at ˜150°C under ultra-high vacuum environment is established to remove the surface oxides completely. It is an essential step to ensure the measurements on electronic states are acquired on stoichimetric, oxide-free clean surface of Bi 2Te3 and Sb2Te3 films. The direct measurement of valence band offsets (VBO) at a real Sb 2Te3/Bi2Te3 interface is designed based on the Kraut model; a special stacking film structure is prepared intentionally: sufficiently thin Sb2Te3 film on top of Bi2Te 3 that photoelectrons from both of them are collected simultaneously. From a

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

Electrodeposition of Metal Matrix Composites and Materials Characterization for Thin-Film Solar Cells

Science.gov (United States)

2017-12-04

Air Mass CNT Carbon Nanotubes DIV Dark Current -Voltage DMA Dynamic Mechanical Analysis EL Electroluminescence FEM Finite Element Method IMM...AFRL-RV-PS- AFRL-RV-PS- TR-2017-0174 TR-2017-0174 ELECTRODEPOSITION OF METAL MATRIX COMPOSITES AND MATERIALS CHARACTERIZATION FOR THIN-FILM SOLAR...research which is exempt from public affairs security and policy review in accordance with AFI 61-201, paragraph 2.3.5.1. This report is available to

Properties of nanostructured undoped ZrO{sub 2} thin film electrolytes by plasma enhanced atomic layer deposition for thin film solid oxide fuel cells

Energy Technology Data Exchange (ETDEWEB)

Cho, Gu Young; Noh, Seungtak; Lee, Yoon Ho; Cha, Suk Won, E-mail: ybkim@hanyang.ac.kr, E-mail: swcha@snu.ac.kr [Department of Mechanical and Aerospace Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Ji, Sanghoon [Graduate School of Convergence Science and Technology, Seoul National University, Iui-dong, Yeongtong-gu, Suwon 443-270 (Korea, Republic of); Hong, Soon Wook; Koo, Bongjun; Kim, Young-Beom, E-mail: ybkim@hanyang.ac.kr, E-mail: swcha@snu.ac.kr [Department of Mechanical Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791 (Korea, Republic of); An, Jihwan [Manufacturing Systems and Design Engineering Programme, Seoul National University of Science and Technology, 232 Gongneung-ro, Nowon-gu, Seoul 139-743 (Korea, Republic of)

2016-01-15

Nanostructured ZrO{sub 2} thin films were prepared by thermal atomic layer deposition (ALD) and by plasma-enhanced atomic layer deposition (PEALD). The effects of the deposition conditions of temperature, reactant, plasma power, and duration upon the physical and chemical properties of ZrO{sub 2} films were investigated. The ZrO{sub 2} films by PEALD were polycrystalline and had low contamination, rough surfaces, and relatively large grains. Increasing the plasma power and duration led to a clear polycrystalline structure with relatively large grains due to the additional energy imparted by the plasma. After characterization, the films were incorporated as electrolytes in thin film solid oxide fuel cells, and the performance was measured at 500 °C. Despite similar structure and cathode morphology of the cells studied, the thin film solid oxide fuel cell with the ZrO{sub 2} thin film electrolyte by the thermal ALD at 250 °C exhibited the highest power density (38 mW/cm{sup 2}) because of the lowest average grain size at cathode/electrolyte interface.

Combinatorial thin film materials science: From alloy discovery and optimization to alloy design

Energy Technology Data Exchange (ETDEWEB)

Gebhardt, Thomas, E-mail: gebhardt@mch.rwth-aachen.de; Music, Denis; Takahashi, Tetsuya; Schneider, Jochen M.

2012-06-30

This paper provides an overview of modern alloy development, from discovery and optimization towards alloy design, based on combinatorial thin film materials science. The combinatorial approach, combining combinatorial materials synthesis of thin film composition-spreads with high-throughput property characterization has proven to be a powerful tool to delineate composition-structure-property relationships, and hence to efficiently identify composition windows with enhanced properties. Furthermore, and most importantly for alloy design, theoretical models and hypotheses can be critically appraised. Examples for alloy discovery, optimization, and alloy design of functional as well as structural materials are presented. Using Fe-Mn based alloys as an example, we show that the combination of modern electronic-structure calculations with the highly efficient combinatorial thin film composition-spread method constitutes an effective tool for knowledge-based alloy design.

Combinatorial thin film materials science: From alloy discovery and optimization to alloy design

International Nuclear Information System (INIS)

Gebhardt, Thomas; Music, Denis; Takahashi, Tetsuya; Schneider, Jochen M.

2012-01-01

This paper provides an overview of modern alloy development, from discovery and optimization towards alloy design, based on combinatorial thin film materials science. The combinatorial approach, combining combinatorial materials synthesis of thin film composition-spreads with high-throughput property characterization has proven to be a powerful tool to delineate composition–structure–property relationships, and hence to efficiently identify composition windows with enhanced properties. Furthermore, and most importantly for alloy design, theoretical models and hypotheses can be critically appraised. Examples for alloy discovery, optimization, and alloy design of functional as well as structural materials are presented. Using Fe-Mn based alloys as an example, we show that the combination of modern electronic-structure calculations with the highly efficient combinatorial thin film composition-spread method constitutes an effective tool for knowledge-based alloy design.

Covalently bonded disordered thin-film materials. Materials Research Society symposium proceedings Volume 498

International Nuclear Information System (INIS)

Siegal, M.P.; Milne, W.I.; Jaskie, J.E.

1998-01-01

The current and potential impact of covalently bonded disordered thin films is enormous. These materials are amorphous-to-nanocrystalline structures made from light atomic weight elements from the first row of the periodic table. Examples include amorphous tetrahedral diamond-like carbon, boron nitride, carbon nitride, boron carbide, and boron-carbon-nitride. These materials are under development for use as novel low-power, high-visibility elements in flat-panel display technologies, cold-cathode sources for microsensors and vacuum microelectronics, encapsulants for both environmental protection and microelectronics, optical coatings for laser windows, and ultra-hard tribological coatings. researchers from 17 countries and a broad range of academic institutions, national laboratories and industrial organizations come together in this volume to report on the status of key areas and recent discoveries. More specifically, the volume is organized into five sections. The first four highlight ongoing work primarily in the area of amorphous/nanocrystalline (disordered) carbon thin films; theoretical and experimental structural characterization; electrical and optical characterizations; growth methods; and cold-cathode electron emission results. The fifth section describes the growth, characterization and application of boron- and carbon-nitride thin films

Characterisation of ferroelectric bulk materials and thin films

CERN Document Server

Cain, Markys G

2014-01-01

This book presents a comprehensive review of the most important methods used in the characterisation of piezoelectric, ferroelectric and pyroelectric materials. It covers techniques for the analysis of bulk materials and thick and thin film materials and devices. There is a growing demand by industry to adapt and integrate piezoelectric materials into ever smaller devices and structures. Such applications development requires the joint development of reliable, robust, accurate and - most importantly - relevant and applicable measurement and characterisation methods and models. In the past f

Cell behaviors on micro-patterned porous thin films

International Nuclear Information System (INIS)

Phong, Ho Quoc; Wang Shuling; Wang, Meng-Jiy

2010-01-01

Thin polymer films with patterned surfaces have drawn tremendous attention in manufacturing advanced electronic, mechanical devices and in biomaterials due to the advantageous properties such as mechanical strength, chemical resistance and optic transparency. The applications can be extended to the fields such as catalysts, antireflection coatings, template for inorganic growth masks, and substrates for cell culturing providing the patterned surface containing micron-sized features. Various methods have been used to fabricate polymers with micro-patterned surfaces such as photolithographic, ink-jet printing, nonsolvent, spin coating in a dry environment, self-organization, and the condensation of monodisperse water droplet on the polymer solution. The physiological functions of mature cells depend on the microenvironment/niche surrounding which can provide proper factors to regulate cell proliferation and differentiation. While designing appropriate scaffolds for tissue engineering, the microstructure is one of the most important factors to be considered. In this work, a facile single-step phase separation method was used to create micro-patterned polymer thin films with concaves or convexes with sizes ranged from 7 to 70 μm. The effects of water content, casting volume and the addition of surfactant on the distribution of pores and substrate morphology were examined. Moreover, detailed observations of fibroblast cells on the micro-patterned thin films were presented to compare and elucidate the roles of surface micro-features and chemical functionalities.

Magnetic Properties of FeNi-Based Thin Film Materials with Different Additives

Directory of Open Access Journals (Sweden)

Cai Liang

2014-07-01

Full Text Available This paper presents a study of FeNi-based thin film materials deposited with Mo, Al and B using a co-sputtering process. The existence of soft magnetic properties in combination with strong magneto-mechanical coupling makes these materials attractive for sensor applications. Our findings show that FeNi deposited with Mo or Al yields magnetically soft materials and that depositing with B further increases the softness. The out-of-plane magnetic anisotropy of FeNi thin films is reduced by depositing with Al and completely removed by depositing with B. The effect of depositing with Mo is dependent on the Mo concentration. The coercivity of FeNiMo and FeNiAl is reduced to less than a half of that of FeNi, and a value as low as 40 A/m is obtained for FeNiB. The surfaces of the obtained FeNiMo, FeNiAl and FeNiB thin films reveal very different morphologies. The surface of FeNiMo shows nano-cracks, while the FeNiAl films show large clusters and fewer nano-cracks. When FeNi is deposited with B, a very smooth morphology is obtained. The crystal structure of FeNiMo strongly depends on the depositant concentration and changes into an amorphous structure at a higher Mo level. FeNiAl thin films remain polycrystalline, even at a very high concentration of Al, and FeNiB films are amorphous, even at a very low concentration of B.

Magnetic properties of FeNi-based thin film materials with different additives

KAUST Repository

Liang, C.

2014-07-04

This paper presents a study of FeNi-based thin film materials deposited with Mo, Al and B using a co-sputtering process. The existence of soft magnetic properties in combination with strong magneto-mechanical coupling makes these materials attractive for sensor applications. Our findings show that FeNi deposited with Mo or Al yields magnetically soft materials and that depositing with B further increases the softness. The out-of-plane magnetic anisotropy of FeNi thin films is reduced by depositing with Al and completely removed by depositing with B. The effect of depositing with Mo is dependent on the Mo concentration. The coercivity of FeNiMo and FeNiAl is reduced to less than a half of that of FeNi, and a value as low as 40 A/m is obtained for FeNiB. The surfaces of the obtained FeNiMo, FeNiAl and FeNiB thin films reveal very different morphologies. The surface of FeNiMo shows nano-cracks, while the FeNiAl films show large clusters and fewer nano-cracks. When FeNi is deposited with B, a very smooth morphology is obtained. The crystal structure of FeNiMo strongly depends on the depositant concentration and changes into an amorphous structure at a higher Mo level. FeNiAl thin films remain polycrystalline, even at a very high concentration of Al, and FeNiB films are amorphous, even at a very low concentration of B. 2014 by the authors.

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...

Multilayer Thin Films Sequential Assembly of Nanocomposite Materials

CERN Document Server

Decher, Gero

2012-01-01

This second, comprehensive edition of the pioneering book in this field has been completely revised and extended, now stretching to two volumes. The result is a comprehensive summary of layer-by-layer assembled, truly hybrid nanomaterials and thin films, covering organic, inorganic, colloidal, macromolecular and biological components, plus the assembly of nanoscale films derived from them on surfaces. Praise for the first edition: "... highly recommended to anyone interested in the field... and to scientists and researchers active in materials development..." –Polymer News With contri

Temperature Effects on a-IGZO Thin Film Transistors Using HfO2 Gate Dielectric Material

Directory of Open Access Journals (Sweden)

Yu-Hsien Lin

2014-01-01

Full Text Available This study investigated the temperature effect on amorphous indium gallium zinc oxide (a-IGZO thin film transistors (TFTs using hafnium oxide (HfO2 gate dielectric material. HfO2 is an attractive candidate as a high-κ dielectric material for gate oxide because it has great potential to exhibit superior electrical properties with a high drive current. In the process of integrating the gate dielectric and IGZO thin film, postannealing treatment is an essential process for completing the chemical reaction of the IGZO thin film and enhancing the gate oxide quality to adjust the electrical characteristics of the TFTs. However, the hafnium atom diffused the IGZO thin film, causing interface roughness because of the stability of the HfO2 dielectric thin film during high-temperature annealing. In this study, the annealing temperature was optimized at 200°C for a HfO2 gate dielectric TFT exhibiting high mobility, a high ION/IOFF ratio, low IOFF current, and excellent subthreshold swing (SS.

Thermally evaporated thin films of SnS for application in solar cell devices

International Nuclear Information System (INIS)

Miles, Robert W.; Ogah, Ogah E.; Zoppi, Guillaume; Forbes, Ian

2009-01-01

SnS (tin sulphide) is of interest for use as an absorber layer and the wider energy bandgap phases e.g. SnS 2 , Sn 2 S 3 and Sn/S/O alloys of interest as Cd-free buffer layers for use in thin film solar cells. In this work thin films of tin sulphide have been thermally evaporated onto glass and SnO 2 :coated glass substrates with the aim of optimising the properties of the material for use in photovoltaic solar cell device structures. In particular the effects of source temperature, substrate temperature, deposition rate and film thickness on the chemical and physical properties of the layers were investigated. Energy dispersive X-ray analysis was used to determine the film composition, X-ray diffraction to determine the phases present and structure of each phase, transmittance and reflectance versus wavelength measurements to determine the energy bandgap and scanning electron microscopy to observe the surface topology and topography and the properties correlated to the deposition parameters. Using the optimised conditions it is possible to produce thin films of tin sulphide that are pinhole free, conformal to the substrate and that consist of densely packed columnar grains. The composition, phases present and the optical properties of the layers deposited were found to be highly sensitive to the deposition conditions. Energy bandgaps in the range 1.55 eV-1.7 eV were obtained for a film thickness of 0.8 μm, and increasing the film thickness to > 1 μm resulted in a reduction of the energy bandgap to less than 1.55 eV. The applicability of using these films in photovoltaic solar cell device structures is also discussed.

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.

Growth of Cu2ZnSnS4(CZTS) by Pulsed Laser Deposition for Thin film Photovoltaic Absorber Material

Science.gov (United States)

Nandur, Abhishek; White, Bruce

2014-03-01

CZTS (Cu2ZnSnS4) has become the subject of intense interest because it is an ideal candidate absorber material for thin-film solar cells with an optimal band gap (1.5 eV), high absorption coefficient (104 cm-1) and abundant elemental components. Pulsed Laser Deposition (PLD) provides excellent control over film composition since thin films are deposited under high vacuum with excellent stoichiometry transfer from the target. CZTS thin films were deposited using PLD from a stoichiometrically close CZTS target (Cu2.6Zn1.1Sn0.7S3.44). The effects of laser energy fluence and substrate temperature and post-deposition sulfur annealing on the surface morphology, composition and optical absorption have been investigated. Optimal CZTS thin films exhibited a band gap of 1.54 eV with an absorption coefficient of 4x104cm-1. A solar cell utilizing PLD grown CZTS with the structure SLG/Mo/CZTS/CdS/ZnO/ITO showed a conversion efficiency of 5.85% with Voc = 376 mV, Jsc = 38.9 mA/cm2 and Fill Factor, FF = 0.40.

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.

Quadruple-Junction Thin-Film Silicon-Based Solar Cells

NARCIS (Netherlands)

Si, F.T.

2017-01-01

The direct utilization of sunlight is a critical energy source in a sustainable future. One of the options is to convert the solar energy into electricity using thin-film silicon-based solar cells (TFSSCs). Solar cells in a triple-junction configuration have exhibited the highest energy conversion

Preparation of thin films, with base to precursor materials of type Cu-In-Se elaborated by electrodeposition for the solar cells elaboration

International Nuclear Information System (INIS)

Fernandez, A.M.

1999-01-01

Thin films of chalcogenide compounds are promising because they have excellent optoelectronic characteristics to be applied in solar cells. In particular, CuInSe 2 and Cd Te thin films have shown high solar to electrical conversion efficiency. However, this efficiency is limited by the method of preparation, in this case, physical vapor deposition techniques are used. In order to increase the area of deposition t is necessary to use chemical methods, for example, electrodeposition technique. In this paper, the preparation of Cu-In-Se precursors thin films by electrochemical method is reported. These precursors were used to build solar cells with 7.9 % of efficiency. (Author)

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)

Study of optoelectronic properties of thin film solar cell materials Cu2ZnSn(S,Se)4 using multiple correlative spatially-resolved spectroscopy techniques

Science.gov (United States)

Chen, Qiong

Containing only earth abundant and environmental friendly elements, quaternary compounds Cu2ZnSnS4 (CZTS) and Cu2ZnSnSe 4 (CZTSe) are considered as promising absorber materials for thin film solar cells. The best record efficiency for this type of thin film solar cell is now 12.6%. As a promising photovoltaic (PV) material, the electrical and optical properties of CZTS(Se) have not been well studied. In this work, an effort has been made to understand the optoelectronic and structural properties, in particular the spatial variations, of CZTS(Se) materials and devices by correlating multiple spatially resolved characterization techniques with sub-micron resolution. Micro-Raman (micro-Raman) spectroscopy was used to analyze the chemistry compositions in CZTS(Se) film; Micro-Photoluminescence (micro-PL) was used to determine the band gap and possible defects. Micro-Laser-Beam-Induced-Current (micro-LBIC) was used to examine the photo-response of CZTS(Se) solar cell in different illumination conditions. Micro-reflectance was used to estimate the reflectance loss. And Micro-I-V measurement was used to compare important electrical parameters from CZTS(Se) solar cells with different device structure or absorber compositions. Scanning electron microscopy and atomic force microscopy were used to characterize the surface morphology. Successfully integrating and correlating these techniques was first demonstrated during the course of this work in our laboratory, and this level of integration and correlation has been rare in the field of PV research. This effort is significant not only for this particular project and also for a wide range of research topics. Applying this approach, in conjunction with high-temperature and high-excitation-power optical spectroscopy, we have been able to reveal the microscopic scale variations among samples and devices that appeared to be very similar from macroscopic material and device characterizations, and thus serve as a very powerful tool

Thin film silicon photovoltaics: Architectural perspectives and technological issues

Energy Technology Data Exchange (ETDEWEB)

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

2009-10-15

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

Thin film plasma coatings from dielectric free-flowing materials

International Nuclear Information System (INIS)

Timofeeva, L.A.; Katrich, S.A.; Solntsev, L.A.

1994-01-01

Fabrication of thin film plasma coatings from insulating free-flowing materials is considered. Molybdenum-tart ammonium coating of 3...5 μ thickness deposited on glassy carbon, aluminium, silicon, nickel, cast iron and steel substrates in 'Bulat-ZT' machine using insulating free-flowing materials cathod was found to form due to adsorption, absorption and dissuasion processes. The use of insulating free-flowing materials coatings allow to exclude pure metals cathods in plasma-plating process

Silicon solar cell performance deposited by diamond like carbon thin film ;Atomic oxygen effects;

Science.gov (United States)

Aghaei, Abbas Ail; Eshaghi, Akbar; Karami, Esmaeil

2017-09-01

In this research, a diamond-like carbon thin film was deposited on p-type polycrystalline silicon solar cell via plasma-enhanced chemical vapor deposition method by using methane and hydrogen gases. The effect of atomic oxygen on the functioning of silicon coated DLC thin film and silicon was investigated. Raman spectroscopy, field emission scanning electron microscopy, atomic force microscopy and attenuated total reflection-Fourier transform infrared spectroscopy were used to characterize the structure and morphology of the DLC thin film. Photocurrent-voltage characteristics of the silicon solar cell were carried out using a solar simulator. The results showed that atomic oxygen exposure induced the including oxidation, structural changes, cross-linking reactions and bond breaking of the DLC film; thus reducing the optical properties. The photocurrent-voltage characteristics showed that although the properties of the fabricated thin film were decreased after being exposed to destructive rays, when compared with solar cell without any coating, it could protect it in atomic oxygen condition enhancing solar cell efficiency up to 12%. Thus, it can be said that diamond-like carbon thin layer protect the solar cell against atomic oxygen exposure.

Solid-phase crystallization of amorphous silicon on ZnO:Al for thin-film solar cells

Energy Technology Data Exchange (ETDEWEB)

Becker, C.; Conrad, E.; Dogan, P.; Fenske, F.; Gorka, B.; Haenel, T.; Lee, K.Y.; Rau, B.; Ruske, F.; Weber, T.; Gall, S.; Rech, B. [Helmholtz-Zentrum Berlin fuer Materialien und Energie (formerly Hahn-Meitner-Institut Berlin), Kekulestr. 5, D-12489 Berlin (Germany); Berginski, M.; Huepkes, J. [Institute of Photovoltaics, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)

2009-06-15

The suitability of ZnO:Al thin films for polycrystalline silicon (poly-Si) thin-film solar cell fabrication was investigated. The electrical and optical properties of 700 -nm-thick ZnO:Al films on glass were analyzed after typical annealing steps occurring during poly-Si film preparation. If the ZnO:Al layer is covered by a 30 nm thin silicon film, the initial sheet resistance of ZnO:Al drops from 4.2 to 2.2 {omega} after 22 h annealing at 600 C and only slightly increases for a 200 s heat treatment at 900 C. A thin-film solar cell concept consisting of poly-Si films on ZnO:Al coated glass is introduced. First solar cell results will be presented using absorber layers either prepared by solid-phase crystallization (SPC) or by direct deposition at 600 C. (author)

Solar cells based on electrodeposited thin films of ZnS, CdS, CdSSe and CdTe

Science.gov (United States)

Weerasinghe, Ajith R.

The motivations of this research were to produce increased efficiency and low-cost solar cells. The production efficiency of Si solar cells has almost reached their theoretical limit, and reducing the manufacturing cost of Si solar cells is difficult to achieve due to the high-energy usage in material purifying and processing stages. Due to the low usage of materials and input energy, thin film solar cells have the potential to reduce the costs. CdS/CdTe thin film solar cells are already the cheapest on $/W basis. The cost of CdTe solar cells can be further reduced if all the semiconducting layers are fabricated using the electrodeposition (ED) method. ED method is scalable, low in the usage of energy and raw materials. These benefits lead to the cost effective production of semiconductors. The conventional method of fabricating CdS layers produces Cd containing waste solutions routinely, which adds to the cost of solar cells.ZnS, CdS and CdS(i-X)Sex buffer and window layers and CdTe absorber layers have been successfully electrodeposited and explored under this research investigation. These layers were fully characterised using complementary techniques to evaluate the material properties. Photoelectrochemical (PEC) studies, optical absorption, X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, atomic force microscopy (AFM) and Raman spectroscopy were utilised to evaluate the material properties of these solid thin film layers. ZnS and CdS thin film layers were electrodeposited from Na-free chemical precursors to avoid the group I element (Na) to reduce deterioration of CdTe devices. Deposition parameters such as, growth substrates, temperature, pH, growth cathodic voltage, stirring rate, time and chemical concentrations were identified to fabricate the above semiconductors. To further optimise these layers, a heat treatment process specific to the material was developed. In addition

Light trapping in thin film solar cells using photonic engineering device concepts

Science.gov (United States)

Mutitu, James Gichuhi

In this era of uncertainty concerning future energy solutions, strong reservations have arisen over the continued use and pursuit of fossil fuels and other conventional sources of energy. Moreover, there is currently a strong and global push for the implementation of stringent measures, in order to reduce the amount of green house gases emitted by every nation. As a consequence, there has emerged a sudden and frantic rush for new renewable energy solutions. In this world of renewable energy technologies is where we find photovoltaic (PV) technology today. However, as is, there are still many issues that need to be addressed before solar energy technologies become economically viable and available to all people, in every part of the world. This renewed interest in the development of solar electricity, has led to the advancement of new avenues that address the issues of cost and efficiency associated with PV. To this end, one of the prominent approaches being explored is thin film solar cell (TFSC) technology, which offers prospects of lower material costs and enables larger units of manufacture than conventional wafer based technology. However, TFSC technologies suffer from one major problem; they have lower efficiencies than conventional wafer based solar cell technologies. This lesser efficiency is based on a number of reasons, one of which is that with less material, there is less volume for the absorption of incident photons. This shortcoming leads to the need for optical light trapping; which is concerned with admitting the maximum amount of light into the solar cell and keeping the light within the structure for as long as possible. In this thesis, I present the fundamental scientific ideas, practice and methodology behind the application of photonic engineering device concepts to increase the light trapping capacity of thin film solar cells. In the introductory chapters, I develop the basic ideas behind light trapping in a sequential manner, where the effects

Using Polarized Spectroscopy to Investigate Order in Thin-Films of Ionic Self-Assembled Materials Based on Azo-Dyes

Science.gov (United States)

Ahmad, Mariam; Andersen, Frederik; Brend Bech, Ári; Bendixen, H. Krestian L.; Nawrocki, Patrick R.; Bloch, Anders J.; Bora, Ilkay; Bukhari, Tahreem A.; Bærentsen, Nicolai V.; Carstensen, Jens; Chima, Smeeah; Colberg, Helene; Dahm, Rasmus T.; Daniels, Joshua A.; Dinckan, Nermin; El Idrissi, Mohamed; Erlandsen, Ricci; Førster, Marc; Ghauri, Yasmin; Gold, Mikkel; Hansen, Andreas; Hansen, Kenn; Helmsøe-Zinck, Mathias; Henriksen, Mathias; Hoffmann, Sophus V.; Hyllested, Louise O. H.; Jensen, Casper; Kallenbach, Amalie S.; Kaur, Kirandip; Khan, Suheb R.; Kjær, Emil T. S.; Kristiansen, Bjørn; Langvad, Sylvester; Lund, Philip M.; Munk, Chastine F.; Møller, Theis; Nehme, Ola M. Z.; Nejrup, Mathilde Rove; Nexø, Louise; Nielsen, Simon Skødt Holm; Niemeier, Nicolai; Nikolajsen, Lasse V.; Nøhr, Peter C. T.; Skaarup Ovesen, Jacob; Paustian, Lucas; Pedersen, Adam S.; Petersen, Mathias K.; Poulsen, Camilla M.; Praeger-Jahnsen, Louis; Qureshi, L. Sonia; Schiermacher, Louise S.; Simris, Martin B.; Smith, Gorm; Smith, Heidi N.; Sonne, Alexander K.; Zenulovic, Marko R.; Winther Sørensen, Alma; Vogt, Emil; Væring, Andreas; Westermann, Jonas; Özcan, Sevin B.

2018-01-01

Three series of ionic self-assembled materials based on anionic azo-dyes and cationic benzalkonium surfactants were synthesized and thin films were prepared by spin-casting. These thin films appear isotropic when investigated with polarized optical microscopy, although they are highly anisotropic. Here, three series of homologous materials were studied to rationalize this observation. Investigating thin films of ordered molecular materials relies to a large extent on advanced experimental methods and large research infrastructure. A statement that in particular is true for thin films with nanoscopic order, where X-ray reflectometry, X-ray and neutron scattering, electron microscopy and atom force microscopy (AFM) has to be used to elucidate film morphology and the underlying molecular structure. Here, the thin films were investigated using AFM, optical microscopy and polarized absorption spectroscopy. It was shown that by using numerical method for treating the polarized absorption spectroscopy data, the molecular structure can be elucidated. Further, it was shown that polarized optical spectroscopy is a general tool that allows determination of the molecular order in thin films. Finally, it was found that full control of thermal history and rigorous control of the ionic self-assembly conditions are required to reproducibly make these materials of high nanoscopic order. Similarly, the conditions for spin-casting are shown to be determining for the overall thin film morphology, while molecular order is maintained. PMID:29462883

Using Polarized Spectroscopy to Investigate Order in Thin-Films of Ionic Self-Assembled Materials Based on Azo-Dyes

Directory of Open Access Journals (Sweden)

Miguel R. Carro-Temboury Martin Kühnel

2018-02-01

Full Text Available Three series of ionic self-assembled materials based on anionic azo-dyes and cationic benzalkonium surfactants were synthesized and thin films were prepared by spin-casting. These thin films appear isotropic when investigated with polarized optical microscopy, although they are highly anisotropic. Here, three series of homologous materials were studied to rationalize this observation. Investigating thin films of ordered molecular materials relies to a large extent on advanced experimental methods and large research infrastructure. A statement that in particular is true for thin films with nanoscopic order, where X-ray reflectometry, X-ray and neutron scattering, electron microscopy and atom force microscopy (AFM has to be used to elucidate film morphology and the underlying molecular structure. Here, the thin films were investigated using AFM, optical microscopy and polarized absorption spectroscopy. It was shown that by using numerical method for treating the polarized absorption spectroscopy data, the molecular structure can be elucidated. Further, it was shown that polarized optical spectroscopy is a general tool that allows determination of the molecular order in thin films. Finally, it was found that full control of thermal history and rigorous control of the ionic self-assembly conditions are required to reproducibly make these materials of high nanoscopic order. Similarly, the conditions for spin-casting are shown to be determining for the overall thin film morphology, while molecular order is maintained.

Using Polarized Spectroscopy to Investigate Order in Thin-Films of Ionic Self-Assembled Materials Based on Azo-Dyes.

Science.gov (United States)

Kühnel, Miguel R Carro-Temboury Martin; Ahmad, Mariam; Andersen, Frederik; Bech, Ári Brend; Bendixen, H Krestian L; Nawrocki, Patrick R; Bloch, Anders J; Bora, Ilkay; Bukhari, Tahreem A; Bærentsen, Nicolai V; Carstensen, Jens; Chima, Smeeah; Colberg, Helene; Dahm, Rasmus T; Daniels, Joshua A; Dinckan, Nermin; Idrissi, Mohamed El; Erlandsen, Ricci; Førster, Marc; Ghauri, Yasmin; Gold, Mikkel; Hansen, Andreas; Hansen, Kenn; Helmsøe-Zinck, Mathias; Henriksen, Mathias; Hoffmann, Sophus V; Hyllested, Louise O H; Jensen, Casper; Kallenbach, Amalie S; Kaur, Kirandip; Khan, Suheb R; Kjær, Emil T S; Kristiansen, Bjørn; Langvad, Sylvester; Lund, Philip M; Munk, Chastine F; Møller, Theis; Nehme, Ola M Z; Nejrup, Mathilde Rove; Nexø, Louise; Nielsen, Simon Skødt Holm; Niemeier, Nicolai; Nikolajsen, Lasse V; Nøhr, Peter C T; Orlowski, Dominik B; Overgaard, Marc; Ovesen, Jacob Skaarup; Paustian, Lucas; Pedersen, Adam S; Petersen, Mathias K; Poulsen, Camilla M; Praeger-Jahnsen, Louis; Qureshi, L Sonia; Ree, Nicolai; Schiermacher, Louise S; Simris, Martin B; Smith, Gorm; Smith, Heidi N; Sonne, Alexander K; Zenulovic, Marko R; Sørensen, Alma Winther; Sørensen, Karina; Vogt, Emil; Væring, Andreas; Westermann, Jonas; Özcan, Sevin B; Sørensen, Thomas Just

2018-02-15

Three series of ionic self-assembled materials based on anionic azo-dyes and cationic benzalkonium surfactants were synthesized and thin films were prepared by spin-casting. These thin films appear isotropic when investigated with polarized optical microscopy, although they are highly anisotropic. Here, three series of homologous materials were studied to rationalize this observation. Investigating thin films of ordered molecular materials relies to a large extent on advanced experimental methods and large research infrastructure. A statement that in particular is true for thin films with nanoscopic order, where X-ray reflectometry, X-ray and neutron scattering, electron microscopy and atom force microscopy (AFM) has to be used to elucidate film morphology and the underlying molecular structure. Here, the thin films were investigated using AFM, optical microscopy and polarized absorption spectroscopy. It was shown that by using numerical method for treating the polarized absorption spectroscopy data, the molecular structure can be elucidated. Further, it was shown that polarized optical spectroscopy is a general tool that allows determination of the molecular order in thin films. Finally, it was found that full control of thermal history and rigorous control of the ionic self-assembly conditions are required to reproducibly make these materials of high nanoscopic order. Similarly, the conditions for spin-casting are shown to be determining for the overall thin film morphology, while molecular order is maintained.

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.

Scalable Production of Mechanically Robust Antireflection Film for Omnidirectional Enhanced Flexible Thin Film Solar Cells.

Science.gov (United States)

Wang, Min; Ma, Pengsha; Yin, Min; Lu, Linfeng; Lin, Yinyue; Chen, Xiaoyuan; Jia, Wei; Cao, Xinmin; Chang, Paichun; Li, Dongdong

2017-09-01

Antireflection (AR) at the interface between the air and incident window material is paramount to boost the performance of photovoltaic devices. 3D nanostructures have attracted tremendous interest to reduce reflection, while the structure is vulnerable to the harsh outdoor environment. Thus the AR film with improved mechanical property is desirable in an industrial application. Herein, a scalable production of flexible AR films is proposed with microsized structures by roll-to-roll imprinting process, which possesses hydrophobic property and much improved robustness. The AR films can be potentially used for a wide range of photovoltaic devices whether based on rigid or flexible substrates. As a demonstration, the AR films are integrated with commercial Si-based triple-junction thin film solar cells. The AR film works as an effective tool to control the light travel path and utilize the light inward more efficiently by exciting hybrid optical modes, which results in a broadband and omnidirectional enhanced performance.

Interfacial Properties of CZTS Thin Film Solar Cell

Directory of Open Access Journals (Sweden)

N. Muhunthan

2014-01-01

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

Materials science in microelectronics II the effects of structure on properties in thin films

CERN Document Server

Machlin, Eugene

2005-01-01

The subject matter of thin-films - which play a key role in microelectronics - divides naturally into two headings: the processing / structure relationship, and the structure / properties relationship. Part II of 'Materials Science in Microelectronics' focuses on the latter of these relationships, examining the effect of structure on the following: Electrical properties Magnetic properties Optical properties Mechanical properties Mass transport properties Interface and junction properties Defects and properties Captures the importance of thin films to microelectronic development Examines the cause / effect relationship of structure on thin film properties.

Pulsed Laser-Induced Effects in the Material Properties of Tungsten Thin Films

Energy Technology Data Exchange (ETDEWEB)

Evans, R [Centro de Investigacion CientIfica y de Educacion Superior de Ensenada, Km. 107 Carretera Tijuana-Ensenada, BC, 22860 (Mexico); Camacho-Lopez, S [Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, Km. 107 Carretera Tijuana-Ensenada, BC, 22860 (Mexico); Camacho-Lopez, M A [Facultad de Quimica, Universidad Autonoma del Estado de Mexico, Paseo Colon y Tollocan, Toluca Edo. de Mexico, 50110 (Mexico); Sanchez-Perez, C [Centro de Ciencias Aplicadas y Desarrollo Tecnologico, UNAM, Apdo. Postal 70-186, Mexico DF 04510 (Mexico); Esparza-GarcIa, A [Centro de Ciencias Aplicadas y Desarrollo Tecnologico, UNAM, Apdo. Postal 70-186, Mexico DF 04510 (Mexico)

2007-04-15

In this work we present evidence of photo-induced effects on crystalline Tungsten (W) films. A frequency doubled Nd:YAG (5ns) laser was used in our experiments. The W thin films were deposited on silicon substrates by the DC-sputtering technique using W (Lesker, 99.95% purity) targets in an argon atmosphere. The crystalline phase of the deposited W films was determined by X-ray diffraction. Our experimental results show clear evidence that several events take place as a consequence of exposure of the W films to the laser nanosecond pulses. One of those events has a chemical effect that results in a significant degree of oxidation of the film; a second event affects the structural nature of the initial W material, resulting into a material phase change; and a third event changes the initially homogeneous morphology of the film into an unexpected porous material film. As it has been confirmed by the experiments, all of these effects are laser fluence dependent. A full post exposure analysis of the W thin films included Energy Dispersive Spectrometry to determine the degree of oxidation of the W film; a micro-Raman system was used to explore and to study the transition of the crystalline W to the amorphous-crystalline WO{sub 3} phase; further analysis with Scanning Electron Microscopy showed a definite laser-induced porosity which changes the initial homogeneous film into a highly porous film with small features in the range from 100 to 300 nm.

Pulsed Laser-Induced Effects in the Material Properties of Tungsten Thin Films

International Nuclear Information System (INIS)

Evans, R; Camacho-Lopez, S; Camacho-Lopez, M A; Sanchez-Perez, C; Esparza-GarcIa, A

2007-01-01

In this work we present evidence of photo-induced effects on crystalline Tungsten (W) films. A frequency doubled Nd:YAG (5ns) laser was used in our experiments. The W thin films were deposited on silicon substrates by the DC-sputtering technique using W (Lesker, 99.95% purity) targets in an argon atmosphere. The crystalline phase of the deposited W films was determined by X-ray diffraction. Our experimental results show clear evidence that several events take place as a consequence of exposure of the W films to the laser nanosecond pulses. One of those events has a chemical effect that results in a significant degree of oxidation of the film; a second event affects the structural nature of the initial W material, resulting into a material phase change; and a third event changes the initially homogeneous morphology of the film into an unexpected porous material film. As it has been confirmed by the experiments, all of these effects are laser fluence dependent. A full post exposure analysis of the W thin films included Energy Dispersive Spectrometry to determine the degree of oxidation of the W film; a micro-Raman system was used to explore and to study the transition of the crystalline W to the amorphous-crystalline WO 3 phase; further analysis with Scanning Electron Microscopy showed a definite laser-induced porosity which changes the initial homogeneous film into a highly porous film with small features in the range from 100 to 300 nm

Spectroscopic investigation of the chemical and electronic properties of chalcogenide materials for thin-film optoelectronic devices

Science.gov (United States)

Horsley, Kimberly Anne

Chalcogen-based materials are at the forefront of technologies for sustainable energy production. This progress has come only from decades of research, and further investigation is needed to continue improvement of these materials. For this dissertation, a number of chalcogenide systems were studied, which have applications in optoelectronic devices, such as LEDs and Photovoltaics. The systems studied include Cu(In,Ga)Se2 (CIGSe) and CuInSe 2 (CISe) thin-film absorbers, CdTe-based photovoltaic structures, and CdTe-ZnO nanocomposite materials. For each project, a sample set was prepared through collaboration with outside institutions, and a suite of spectroscopy techniques was employed to answer specific questions about the system. These techniques enabled the investigation of the chemical and electronic structure of the materials, both at the surface and towards the bulk. CdS/Cu(In,Ga)Se2 thin-films produced from the roll-to-roll, ambient pressure, Nanosolar industrial line were studied. While record-breaking efficiency cells are usually prepared in high-vacuum (HV) or ultra-high vacuum (UHV) environments, these samples demonstrate competitive mass-production efficiency without the high-cost deposition environment. We found relatively low levels of C contaminants, limited Na and Se oxidation, and a S-Se intermixing at the CdS/CIGSe interface. The surface band gap compared closely to previously investigated CIGSe thin-films deposited under vacuum, illustrating that roll-to-roll processing is a promising and less-expensive alternative for solar cell production. An alternative deposition process for CuInSe2 was also studied, in collaboration with the University of Luxembourg. CuInSe2 absorbers were prepared with varying Cu content and surface treatments to investigate the potential to produce an absorber with a Cu-rich bulk and Cu-poor surface. This is desired to combine the bulk characteristics of reduced defects and larger grains in Cu-rich films, while maintaining

Thin films of copper antimony sulfide: A photovoltaic absorber material

Energy Technology Data Exchange (ETDEWEB)

Ornelas-Acosta, R.E. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, San Nicolás de los Garza, Nuevo León 66450 (Mexico); Shaji, S. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, San Nicolás de los Garza, Nuevo León 66450 (Mexico); Universidad Autónoma de Nuevo León-CIIDIT, Apodaca, Nuevo León (Mexico); Avellaneda, D.; Castillo, G.A.; Das Roy, T.K. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, San Nicolás de los Garza, Nuevo León 66450 (Mexico); Krishnan, B., E-mail: kbindu_k@yahoo.com [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, San Nicolás de los Garza, Nuevo León 66450 (Mexico); Universidad Autónoma de Nuevo León-CIIDIT, Apodaca, Nuevo León (Mexico)

2015-01-15

Highlights: • CuSbS{sub 2} thin films were prepared by heating Sb{sub 2}S{sub 3}/Cu layers. • Analyzed the structure, composition, optical, and electrical properties. • PV structures: glass/SnO{sub 2}:F/n-CdS/p-CuSbS{sub 2}/C/Ag were formed at different conditions. • The PV parameters (J{sub sc}, V{sub oc}, and FF) were evaluated from the J–V characteristics. • J{sub sc}: 0.52–3.20 mA/cm{sup 2}, V{sub oc}:187–323 mV, FF: 0.27–0.48 were obtained. - Abstract: In this work, we report preparation and characterization of CuSbS{sub 2} thin films by heating glass/Sb{sub 2}S{sub 3}/Cu layers and their use as absorber material in photovoltaic structures: glass/SnO{sub 2}:F/n-CdS/p-CuSbS{sub 2}/C/Ag. The Sb{sub 2}S{sub 3} thin films of 600 nm were prepared by chemical bath deposition on which copper thin films of 50 nm were thermally evaporated, and the glass/Sb{sub 2}S{sub 3}/Cu multilayers were heated in vacuum at different temperatures. X-ray diffraction analysis showed the formation of orthorhombic CuSbS{sub 2} after heating the precursor layers. Studies on identification and chemical state of the elements were done using X-ray photoelectron spectroscopy. The optical band gap of the CuSbS{sub 2} thin films was 1.55 eV and the thin films were photoconductive. The photovoltaic parameters of the devices using CuSbS{sub 2} as absorber and CdS as window layer were evaluated from the J–V curves, yielding J{sub sc}, V{sub oc}, and FF values in the range of 0.52–3.20 mA/cm{sup 2}, 187–323 mV, and 0.27–0.48, respectively, under illumination of AM1.5 radiation.

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

Low-Dimensional Nanomaterials as Active Layer Components in Thin-Film Photovoltaics

Science.gov (United States)

Shastry, Tejas Attreya

Thin-film photovoltaics offer the promise of cost-effective and scalable solar energy conversion, particularly for applications of semi-transparent solar cells where the poor absorption of commercially-available silicon is inadequate. Applications ranging from roof coatings that capture solar energy to semi-transparent windows that harvest the immense amount of incident sunlight on buildings could be realized with efficient and stable thin-film solar cells. However, the lifetime and efficiency of thin-film solar cells continue to trail their inorganic silicon counterparts. Low-dimensional nanomaterials, such as carbon nanotubes and two-dimensional metal dichalcogenides, have recently been explored as materials in thin-film solar cells due to their exceptional optoelectronic properties, solution-processability, and chemical inertness. Thus far, issues with the processing of these materials has held back their implementation in efficient photovoltaics. This dissertation reports processing advances that enable demonstrations of low-dimensional nanomaterials in thin-film solar cells. These low-dimensional photovoltaics show enhanced photovoltaic efficiency and environmental stability in comparison to previous devices, with a focus on semiconducting single-walled carbon nanotubes as an active layer component. The introduction summarizes recent advances in the processing of carbon nanotubes and their implementation through the thin-film photovoltaic architecture, as well as the use of two-dimensional metal dichalcogenides in photovoltaic applications and potential future directions for all-nanomaterial solar cells. The following chapter reports a study of the interaction between carbon nanotubes and surfactants that enables them to be sorted by electronic type via density gradient ultracentrifugation. These insights are utilized to construct of a broad distribution of carbon nanotubes that absorb throughout the solar spectrum. This polychiral distribution is then shown

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

Transparent conductive oxides for thin-film silicon solar cells

NARCIS (Netherlands)

Löffler, J.

2005-01-01

This thesis describes research on thin-film silicon solar cells with focus on the transparent conductive oxide (TCO) for such devices. In addition to the formation of a transparent and electrically conductive front electrode for the solar cell allowing photocurrent collection with low ohmic losses,

Cytotoxicity Evaluation of Anatase and Rutile TiO₂ Thin Films on CHO-K1 Cells in Vitro.

Science.gov (United States)

Cervantes, Blanca; López-Huerta, Francisco; Vega, Rosario; Hernández-Torres, Julián; García-González, Leandro; Salceda, Emilio; Herrera-May, Agustín L; Soto, Enrique

2016-07-26

Cytotoxicity of titanium dioxide (TiO₂) thin films on Chinese hamster ovary (CHO-K1) cells was evaluated after 24, 48 and 72 h of culture. The TiO₂ thin films were deposited using direct current magnetron sputtering. These films were post-deposition annealed at different temperatures (300, 500 and 800 °C) toward the anatase to rutile phase transformation. The root-mean-square (RMS) surface roughness of TiO₂ films went from 2.8 to 8.08 nm when the annealing temperature was increased from 300 to 800 °C. Field emission scanning electron microscopy (FESEM) results showed that the TiO₂ films' thickness values fell within the nanometer range (290-310 nm). Based on the results of the tetrazolium dye and trypan blue assays, we found that TiO₂ thin films showed no cytotoxicity after the aforementioned culture times at which cell viability was greater than 98%. Independently of the annealing temperature of the TiO₂ thin films, the number of CHO-K1 cells on the control substrate and on all TiO₂ thin films was greater after 48 or 72 h than it was after 24 h; the highest cell survival rate was observed in TiO₂ films annealed at 800 °C. These results indicate that TiO₂ thin films do not affect mitochondrial function and proliferation of CHO-K1 cells, and back up the use of TiO₂ thin films in biomedical science.

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.

Cuinse2 Thin Film For Solar Cell By Flash Evaporation

Directory of Open Access Journals (Sweden)

A.H. Soepardjo

2009-11-01

Full Text Available Deposition of thin films for material solar cell CuInSe2 are relatively simple. In this research mainly focused on the use of flash evaporation method, and the material created can then be characterized by optical and electrical properties. The optical characterization is done by X-ray Diffraction (XRD, Energy Dispersive Spectroscopy (EDS, and transmission and reflection by UV-VIS spectrophotometry. Electrical characterization is done by utilizing the Hall effect equipment. From these characterization, the atomic structure, absorption coefficient, energy gap, material type, composition of each elements and the mobility of CuInSe2 can be measured and determined. During process evaporation were carried out at substrate temperatures the range between 20ºC-415ºC.

Accelerated stress testing of thin film solar cells: Development of test methods and preliminary results

Science.gov (United States)

Lathrop, J. W.

1985-01-01

If thin film cells are to be considered a viable option for terrestrial power generation their reliability attributes will need to be explored and confidence in their stability obtained through accelerated testing. Development of a thin film accelerated test program will be more difficult than was the case for crystalline cells because of the monolithic construction nature of the cells. Specially constructed test samples will need to be fabricated, requiring committment to the concept of accelerated testing by the manufacturers. A new test schedule appropriate to thin film cells will need to be developed which will be different from that used in connection with crystalline cells. Preliminary work has been started to seek thin film schedule variations to two of the simplest tests: unbiased temperature and unbiased temperature humidity. Still to be examined are tests which involve the passage of current during temperature and/or humidity stress, either by biasing in the forward (or reverse) directions or by the application of light during stress. Investigation of these current (voltage) accelerated tests will involve development of methods of reliably contacting the thin conductive films during stress.

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.

A computational study of the piezoelectric response due to the material effect in periodic, single island thin films and the geometric effect in periodic, bi-island thin films

International Nuclear Information System (INIS)

Liu, B.; Bhattacharyya, A.

2010-01-01

The electromechanical response of a square-periodic array of circular piezoelectric (PE) thin films alternating with non-piezoelectric (NPE) films is studied in this paper. The material effects are studied for four film/substrate combinations in absence of NPE films for which it is found that if d zxx zzz (z-axis being normal to the interfacial plane between the film and the substrate), it results in reduced substrate bending leading to reduced degradation in the electromechanical response of the thin film. The bi-island structure is studied for zinc oxide on strontium titanate, and, in general, it is seen that the NPE films not only reduce degradation of the electromechanical response of the PE films but also increase their internal stresses; the effect on the former is less than the latter. These effects are most prominent when the circular NPE thin films fill the space between the PE thin films and are elastically very stiff compared to the substrate.

Magnetic properties of FeNi-based thin film materials with different additives

KAUST Repository

Liang, C.; Gooneratne, C.P.; Wang, Q.X.; Liu, Y.; Gianchandani, Y.; Kosel, Jü rgen

2014-01-01

This paper presents a study of FeNi-based thin film materials deposited with Mo, Al and B using a co-sputtering process. The existence of soft magnetic properties in combination with strong magneto-mechanical coupling makes these materials

Annealing enhancement effect by light illumination on proton irradiated Cu(In, Ga)Se2 thin-film solar cells

International Nuclear Information System (INIS)

Kawakita, Shirou; Imaizumi, Mitsuru; Matsuda, Sumio; Yamaguchi, Masafumi; Kushiya, Katsumi; Ohshima, Takeshi; Itoh, Hisayoshi

2002-01-01

In this paper, we investigated the high radiation tolerance of copper indium gallium di-selenide (CIGS) thin-film solar cells by conducting in situ measurements of short circuit current and open circuit voltage of CIGS thin-film solar cells during and after proton irradiation under short circuit condition. We found that the annealing rate of proton-induced defects in CIGS thin-film solar cells under light illumination with an AM0 solar simulator is higher than that under dark conditions. The activation energy of proton-induced defects in the CIGS thin-film solar cells with (without) light illumination is 0.80 eV (0.92 eV), which implies on enhanced defect annealing rate in CIGS thin-film solar cells due to minority-carrier injection. (author)

Osteoblast Adhesion on Cathodic Arc Plasma Deposited Nano-Multilayered TiCrAlSiN Thin Films

Energy Technology Data Exchange (ETDEWEB)

Kim, Sun Kyu [University of Ulsan, Ulsan (Korea, Republic of); Pham, Vuong Hung [Hanoi University of Science and Technology (HUST), Hanoi (Viet Nam)

2014-03-15

Adhesion of osteoblast cells to TiCrAlSiN thin films was evaluated in vitro. Ti and TiCrAlSiN thin films were deposited on glass substrates by cathodic arc deposition. Surface roughness and chemistry of the TiCrAlSiN thin films was characterized by AFM and EPMA, respectively. Ti and TiCrAlSiN thin films and glass coverslips were cultured with human osteoblast cells (hFOB 1.19). The cell cytoskeleton was analyzed by observing the organization of actin stress fibers and microtubules. Cell proliferation was investigated by MTT assay and visualization. Focal contact adhesion was studied by observing the vinculin density. The results indicated that the TiCrAlSiN coating significantly influenced the actin cytoskeleton and microtubule organization. Human osteoblasts hFOB attached and proliferated better on TiCrAlSiN thin films with more focal contact adhesions than on Ti thin films or glass surfaces. These results suggest that TiCrAlSiN thin films can be an implantable material where the maximum cell adhesion is required.

OUT Success Stories: Thin-Film PV: Leadership in Materials R and D

International Nuclear Information System (INIS)

Pitchford, P.

2002-01-01

Photovoltaics (PV) is a modern energy technology that makes use of semiconductor materials to convert sunlight directly to electricity. The idea of thin film technology is to produce truly low-cost PV devices by using pennies worth of active semiconductor materials

Performance of a polymer electrolyte membrane fuel cell with thin film catalyst electrodes

Energy Technology Data Exchange (ETDEWEB)

Chun, Young Gab; Kim, Chang Soo; Peck, Dong Hyun; Shin, Dong Ryul [Korea Institute of Energy Research, Taejon (Korea, Republic of)

1998-03-15

In order to develop a kW-class polymer electrolyte membrane fuel cell (PEMFC), several electrodes have been fabricated by different catalyst layer preparation procedures and evaluated based on the cell performance. Conventional carbon paper and carbon cloth electrodes were fabricated using a ptfe-bonded Pt/C electrol catalyst by coating and rolling methods. Thin-film catalyst/ionomer composite layers were also formed on the membrane by direct coating and transfer printing techniques. The performance evaluation with catalyst layer preparation methods was carried out using a large or small electrode single cell. Conventional and thin film membrane and electrode assemblies (MEAs) with small electrode area showed a performance of 350 and 650 mA/cm{sup 2} at 0.6 V, respectively. The performance of direct coated thin film catalyst layer with 300 cm{sup 2} MEAs was higher than those of the conventional and transfer printing technique MEAs. The influence of some characteristic parameters of the thin film electrode on electrochemical performance was examined. Various other aspects of overall operation of PEMFC stacks were also discussed. (orig.)

Thin film CIGS solar cells with a novel low cost process - Final report

Energy Technology Data Exchange (ETDEWEB)

Tiwari, A. N.; Romanyuk, Y.

2010-01-15

Novel manufacturing routes for efficient and low-cost Cu(In,Ga)Se{sub 2} (called CIGS) thin film solar cells are explored and patented. CIGS has proven its suitability for highly efficient and extremely stable solar cells. The low-cost methods allow impurity free material synthesis, fast large-area deposition, high material utilization and a very short energy payback time with drastically lower manufacturing costs. Two non-vacuum, solution-based approaches are investigated to deposit thin layers of CIGS. The first approach considers incorporation of copper into indium gallium selenide precursor layers by ion-exchange from aqueous or organic solutions. Organic solutions provide faster copper incorporation and do not corrode the metal back contact. Solar cells processed from selenized precursor films exhibit efficiencies of up to 4.1%. The second approach with paste coating of inorganic salt solution results in a solar cell efficiency of 4% (record 6.7%), where further improvements are hindered by the presence of the residual carbon layer. Using alternative organic binders, pre-deposited selenium layers, non-binder recipes helps to avoid the carbon layer although the obtained layers are inhomogeneous and contain impurity phases. A patent for the ion-exchange approach is pending, and the obtained research results on the paste coating approach will be scrutinized during new European FP7 project 'NOVA-CIGS'. (authors)

Vapor transport deposition of antimony selenide thin film solar cells with 7.6% efficiency.

Science.gov (United States)

Wen, Xixing; Chen, Chao; Lu, Shuaicheng; Li, Kanghua; Kondrotas, Rokas; Zhao, Yang; Chen, Wenhao; Gao, Liang; Wang, Chong; Zhang, Jun; Niu, Guangda; Tang, Jiang

2018-06-05

Antimony selenide is an emerging promising thin film photovoltaic material thanks to its binary composition, suitable bandgap, high absorption coefficient, inert grain boundaries and earth-abundant constituents. However, current devices produced from rapid thermal evaporation strategy suffer from low-quality film and unsatisfactory performance. Herein, we develop a vapor transport deposition technique to fabricate antimony selenide films, a technique that enables continuous and low-cost manufacturing of cadmium telluride solar cells. We improve the crystallinity of antimony selenide films and then successfully produce superstrate cadmium sulfide/antimony selenide solar cells with a certified power conversion efficiency of 7.6%, a net 2% improvement over previous 5.6% record of the same device configuration. We analyze the deep defects in antimony selenide solar cells, and find that the density of the dominant deep defects is reduced by one order of magnitude using vapor transport deposition process.

Ultrasonic Substrate Vibration-Assisted Drop Casting (SVADC) for the Fabrication of Photovoltaic Solar Cell Arrays and Thin-Film Devices.

Science.gov (United States)

Eslamian, Morteza; Zabihi, Fatemeh

2015-12-01

A simple, low-cost, versatile, and potentially scalable casting method is proposed for the fabrication of micro- and nano-thin films, herein termed as ultrasonic "substrate vibration-assisted drop casting" (SVADC). The impingement of a solution drop onto a substrate in a simple process called drop casting, usually results in spreading of the liquid solution and the formation of a non-uniform thin solid film after solvent evaporation. Our previous and current supporting results, as well as few similar reports by others, confirm that imposing ultrasonic vibration on the substrate can simply convert the uncontrollable drop casting method into a controllable coating technique. Therefore, the SVADC may be used to fabricate an array of emerging thin-film solar cells, such as polymer, perovskite, and quantum-dot solar cells, as well as other small thin-film devices, in a roll-to-roll and automated fabrication process. The preliminary results demonstrate a ten-fold increase in electrical conductivity of PSS made by SVADC compared with the film made by conventional drop casting. Also, simple planar perovskite solar cells made here using SVADC show promising performance with an efficiency of over 3 % for a simple structure without performing process optimization or using expensive materials and treatments.

Development of A Thin Film Crystalline Silicon Solar Cell

International Nuclear Information System (INIS)

Sopori, B.; Chen, W.; Zhang, Y.

1998-01-01

A new design for a single junction, thin film Si solar cell is presented. The cell design is compatible with low-temperature processing required for the use of a low-cost glass substrate, and includes effective light trapping and impurity gettering. Elements of essential process steps are discussed

The Cu2ZnSnSe4 thin films solar cells synthesized by electrodeposition route

Science.gov (United States)

Li, Ji; Ma, Tuteng; Wei, Ming; Liu, Weifeng; Jiang, Guoshun; Zhu, Changfei

2012-06-01

An electrodeposition route for preparing Cu2ZnSnSe4 thin films for thin film solar cell absorber layers is demonstrated. The Cu2ZnSnSe4 thin films are prepared by co-electrodeposition Cu-Zn-Sn metallic precursor and subsequently annealing in element selenium atmosphere. The structure, composition and optical properties of the films were investigated by X-ray diffraction (XRD), Raman spectrometry, energy dispersive spectrometry (EDS) and UV-VIS absorption spectroscopy. The Cu2ZnSnSe4 thin film with high crystalline quality was obtained, the band gap and absorption coefficient were 1.0 eV and 10-4 cm-1, which is quite suitable for solar cells fabrication. A solar cell with the structure of ZnO:Al/i-ZnO/CdS/Cu2ZnSnSe4/Mo/glass was fabricated and achieved an conversion efficiency of 1.7%.

Development of a cell culture surface conversion technique using alginate thin film for evaluating effect upon cellular differentiation

International Nuclear Information System (INIS)

Nakashima, Y.; Tsusu, K.; Minami, K.; Nakanishi, Y.

2014-01-01

Here, we sought to develop a cell culture surface conversion technique that would not damage living cells. An alginate thin film, formed on a glass plate by spin coating of sodium alginate solution and dipping into calcium chloride solution, was used to inhibit adhesion of cells. The film could be removed by ethylenediaminetetraacetate (EDTA) at any time during cell culture, permitting observation of cellular responses to conversion of the culture surface in real time. Additionally, we demonstrated the validity of the alginate thin film coating method and the performance of the film. The thickness of the alginate thin film was controlled by varying the rotation speed during spin coating. Moreover, the alginate thin film completely inhibited the adhesion of cultured cells to the culture surface, irrespective of the thickness of the film. When the alginate thin film was removed from the culture surface by EDTA, the cultured cells adhered to the culture surface, and their morphology changed. Finally, we achieved effective differentiation of C2C12 myoblasts into myotube cells by cell culture on the convertible culture surface, demonstrating the utility of our novel technique

Textured surface boron-doped ZnO transparent conductive oxides on polyethylene terephthalate substrates for Si-based thin film solar cells

International Nuclear Information System (INIS)

Chen Xinliang; Lin Quan; Ni Jian; Zhang Dekun; Sun Jian; Zhao Ying; Geng Xinhua

2011-01-01

Textured surface boron-doped zinc oxide (ZnO:B) thin films were directly grown via low pressure metal organic chemical vapor deposition (LP-MOCVD) on polyethylene terephthalate (PET) flexible substrates at low temperatures and high-efficiency flexible polymer silicon (Si) based thin film solar cells were obtained. High purity diethylzinc and water vapors were used as source materials, and diborane was used as an n-type dopant gas. P-i-n silicon layers were fabricated at ∼ 398 K by plasma enhanced chemical vapor deposition. These textured surface ZnO:B thin films on PET substrates (PET/ZnO:B) exhibit rough pyramid-like morphology with high transparencies (T ∼ 80%) and excellent electrical properties (Rs ∼ 10 Ω at d ∼ 1500 nm). Finally, the PET/ZnO:B thin films were applied in flexible p-i-n type silicon thin film solar cells (device structure: PET/ZnO:B/p-i-n a-Si:H/Al) with a high conversion efficiency of 6.32% (short-circuit current density J SC = 10.62 mA/cm 2 , open-circuit voltage V OC = 0.93 V and fill factor = 64%).

Broadband back grating design for thin film solar cells

KAUST Repository

Janjua, Bilal; Jabbour, Ghassan E.

2013-01-01

In this paper, design based on tapered circular grating structure was studied, to provide broadband enhancement in thin film amorphous silicon solar cells. In comparison to planar structure an absorption enhancement of ~ 7% was realized.

Comparative alternative materials assessment to screen toxicity hazards in the life cycle of CIGS thin film photovoltaics

International Nuclear Information System (INIS)

Eisenberg, Daniel A.; Yu, Mengjing; Lam, Carl W.; Ogunseitan, Oladele A.; Schoenung, Julie M.

2013-01-01

Highlights: • Comparative alternatives assessment of thin film manufacturing technologies. • Development of chemical alternatives assessment in a life cycle context. • Screening of manufacturing and solar cell hazardous substances simultaneously. -- Abstract: Copper–indium–gallium–selenium–sulfide (CIGS) thin film photovoltaics are increasingly penetrating the market supply for consumer solar panels. Although CIGS is attractive for producing less greenhouse gas emissions than fossil-fuel based energy sources, CIGS manufacturing processes and solar cell devices use hazardous materials that should be carefully considered in evaluating and comparing net environmental benefits of energy products. Through this research, we present a case study on the toxicity hazards associated with alternative materials selection for CIGS manufacturing. We applied two numeric models, The Green Screen for Safer Chemicals™ and the Toxic Potential Indicator. To improve the sensitivity of the model outputs, we developed a novel, life cycle thinking based hazard assessment method that facilitates the projection of hazards throughout material life cycles. Our results show that the least hazardous CIGS solar cell device and manufacturing protocol consist of a titanium substrate, molybdenum metal back electrode, CuInS 2 p-type absorber deposited by spray pyrolysis, ZnS buffer deposited by spray ion layer gas reduction, ZnO:Ga transparent conducting oxide (TCO) deposited by sputtering, and the encapsulant polydimethylsiloxane

Characterization of Nanocrystalline SiGe Thin Film Solar Cell with Double Graded-Dead Absorption Layer

Directory of Open Access Journals (Sweden)

Chao-Chun Wang

2012-01-01

Full Text Available The nanocrystalline silicon-germanium (nc-SiGe thin films were deposited by high-frequency (27.12 MHz plasma-enhanced chemical vapor deposition (HF-PECVD. The films were used in a silicon-based thin film solar cell with graded-dead absorption layer. The characterization of the nc-SiGe films are analyzed by scanning electron microscopy, UV-visible spectroscopy, and Fourier transform infrared absorption spectroscopy. The band gap of SiGe alloy can be adjusted between 0.8 and 1.7 eV by varying the gas ratio. For thin film solar cell application, using double graded-dead i-SiGe layers mainly leads to an increase in short-circuit current and therefore cell conversion efficiency. An initial conversion efficiency of 5.06% and the stabilized efficiency of 4.63% for an nc-SiGe solar cell were achieved.

Direct current magnetron sputter-deposited ZnO thin films

International Nuclear Information System (INIS)

Hoon, Jian-Wei; Chan, Kah-Yoong; Krishnasamy, Jegenathan; Tou, Teck-Yong; Knipp, Dietmar

2011-01-01

Zinc oxide (ZnO) is a very promising electronic material for emerging transparent large-area electronic applications including thin-film sensors, transistors and solar cells. We fabricated ZnO thin films by employing direct current (DC) magnetron sputtering deposition technique. ZnO films with different thicknesses ranging from 150 nm to 750 nm were deposited on glass substrates. The deposition pressure and the substrate temperature were varied from 12 mTorr to 25 mTorr, and from room temperature to 450 deg. C, respectively. The influence of the film thickness, deposition pressure and the substrate temperature on structural and optical properties of the ZnO films was investigated using atomic force microscopy (AFM) and ultraviolet-visible (UV-Vis) spectrometer. The experimental results reveal that the film thickness, deposition pressure and the substrate temperature play significant role in the structural formation and the optical properties of the deposited ZnO thin films.

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.

Influence of thin film thickness of working electrodes on photovoltaic characteristics of dye-sensitized solar cells

Directory of Open Access Journals (Sweden)

Lai Yeong-Lin

2017-01-01

Full Text Available This paper presents the study of the influence of thin film thickness of working electrodes on the photovoltaic characteristics of dye-sensitized solar cells. Titanium dioxide (TiO2 thin films, with the thickness from 7.67 to 24.3 μm, were used to fabricate the working electrodes of dye-sensitized solar cells (DSSCs. A TiO2 film was coated on a fluorine-doped tin oxide (FTO conductive glass substrate and then sintered in a high-temperature furnace. On the other hand, platinum (Pt solution was coated onto an FTO substrate for the fabrication of the counter electrode of a DSSC. The working electrode immersed in a dye, the counter electrode, and the electrolyte were assembled to complete a sandwich-structure DSSC. The material analysis of the TiO2 films of DSSCs was carried out by scanning electron microscopy (SEM and ultraviolet-visible (UV-Vis spectroscopy, while the photovoltaic characteristics of DSSCs were measured by an AM-1.5 sunlight simulator. The light transmittance characteristics of the TiO2 working electrode depend on the TiO2 film thickness. The thin film thickness of the working electrode also affects the light absorption of a dye and results in the photovoltaic characteristics of the DSSC, including open-circuited voltage (VOC, short-circuited current density (JSC, fill factor, and photovoltaic conversion efficiency.

Light trapping with plasmonic back contacts in thin-film silicon solar cells

Energy Technology Data Exchange (ETDEWEB)

Paetzold, Ulrich Wilhelm

2013-02-08

Trapping light in silicon solar cells is essential as it allows an increase in the absorption of incident sunlight in optically thin silicon absorber layers. This way, the costs of the solar cells can be reduced by lowering the material consumption and decreasing the physical constraints on the material quality. In this work, plasmonic light trapping with Ag back contacts in thin-film silicon solar cells is studied. Solar cell prototypes with plasmonic back contacts are presented along with optical simulations of these devices and general design considerations of plasmonic back contacts. Based on three-dimensional electromagnetic simulations, the conceptual design of plasmonic nanostructures on Ag back contacts in thin-film silicon solar cells is studied in this work. Optimizations of the nanostructures regarding their ability to scatter incident light at low optical losses into large angles in the silicon absorber layers of the thin-film silicon solar cells are presented. Geometrical parameters as well as the embedding dielectric layer stack of the nanostructures on Ag layers are varied. Periodic as well as isolated hemispherical Ag nanostructures of dimensions above 200 nm are found to scatter incident light at high efficiencies and low optical losses. Hence, these nanostructures are of interest for light trapping in solar cells. In contrast, small Ag nanostructures of dimension below 100 nm are found to induce optical losses. At the surface of randomly textured Ag back contacts small Ag nanostructures exist which induce optical losses. In this work, the relevance of these localized plasmon induced optical losses as well as optical losses caused by propagating plasmons are investigated with regard to the reflectance of the textured back contacts. In state-of-the-art solar cells, the plasmon-induced optical losses are shifted out of the relevant wavelength range by incorporating a ZnO:Al interlayer of low refractive index at the back contact. The additional but

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

Poly(vinyl acetate)/clay nanocomposite materials for organic thin film transistor application.

Science.gov (United States)

Park, B J; Sung, J H; Park, J H; Choi, J S; Choi, H J

2008-05-01

Nanocomposite materials of poly(vinyl acetate) (PVAc) and organoclay were fabricated, in order to be utilized as dielectric materials of the organic thin film transistor (OTFT). Spin coating condition of the nanocomposite solution was examined considering shear viscosity of the composite materials dissolved in chloroform. Intercalated structure of the PVAc/clay nanocomposites was characterized using both wide-angle X-ray diffraction and TEM. Fracture morphology of the composite film on silicon wafer was also observed by SEM. Dielectric constant (4.15) of the nanocomposite materials shows that the PVAc/clay nanocomposites are applicable for the gate dielectric materials.

Investigation of blister formation in sputtered Cu{sub 2}ZnSnS{sub 4} absorbers for thin film solar cells

Energy Technology Data Exchange (ETDEWEB)

Bras, Patrice, E-mail: patrice.bras@angstrom.uu.se [Midsummer AB, Elektronikhöjden 6, SE-17543 Järfälla, Sweden and Solid State Electronics, Angström Laboratory, Uppsala University, Box 534, SE-75121 Uppsala (Sweden); Sterner, Jan [Midsummer AB, Elektronikhöjden 6, SE-17543 Järfälla (Sweden); Platzer-Björkman, Charlotte [Solid State Electronics, Angström Laboratory, Uppsala University, Box 534, SE-75121 Uppsala (Sweden)

2015-11-15

Blister formation in Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films sputtered from a quaternary compound target is investigated. While the thin film structure, composition, and substrate material are not correlated to the blister formation, a strong link between sputtering gas entrapment, in this case argon, and blistering effect is found. It is shown that argon is trapped in the film during sputtering and migrates to locally form blisters during the high temperature annealing. Blister formation in CZTS absorbers is detrimental for thin film solar cell fabrication causing partial peeling of the absorber layer and potential shunt paths in the complete device. Reduced sputtering gas entrapment, and blister formation, is seen for higher sputtering pressure, higher substrate temperature, and change of sputtering gas to larger atoms. This is all in accordance with previous publications on blister formation caused by sputtering gas entrapment in other materials.

Aging effects of plasma polymerized ethylenediamine (PPEDA) thin films on cell-adhesive implant coatings

International Nuclear Information System (INIS)

Testrich, H.; Rebl, H.; Finke, B.; Hempel, F.; Nebe, B.; Meichsner, J.

2013-01-01

Thin plasma polymer films from ethylenediamine were deposited on planar substrates placed on the powered electrode of a low pressure capacitively coupled 13.56 MHz discharge. The chemical composition of the plasma polymer films was analyzed by Fourier Transform Infrared Reflection Absorption Spectroscopy (FT-IRRAS) as well as by X-ray photoelectron spectroscopy (XPS) after derivatization of the primary amino groups. The PPEDA films undergo an alteration during the storage in ambient air, particularly, due to reactions with oxygen. The molecular changes in PPEDA films were studied over a long-time period of 360 days. Simultaneously, the adhesion of human osteoblast-like cells MG-63 (ATCC) was investigated on PPEDA coated corundum blasted titanium alloy (Ti-6Al-4V), which is applied as implant material in orthopedic surgery. The cell adhesion was determined by flow cytometry and the cell shape was analyzed by scanning electron microscopy. Compared to uncoated reference samples a significantly enhanced cell adhesion and proliferation were measured for PPEDA coated samples, which have been maintained after long-time storage in ambient air and additional sterilization by γ−irradiation. - Highlights: • Development of cell-adhesive nitrogen-rich coatings for biomedical applications. • Plasma polymer films from low pressure 13.56 MHz discharge in argon-ethylenediamine. • Enhanced osteoblast adhesion/proliferation on coated implant material (Ti-6Al-4V). • Despite film aging over 360 days the enhanced cell adhesion of the coating remains. • No influence of additional y-sterilization on the enhanced cell adhesion

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 of thin films and materials utilizing a gaseous catalyst

Science.gov (United States)

Morse, Daniel E; Schwenzer, Birgit; Gomm, John R; Roth, Kristian M; Heiken, Brandon; Brutchey, Richard

2013-10-29

A method for the fabrication of nanostructured semiconducting, photoconductive, photovoltaic, optoelectronic and electrical battery thin films and materials at low temperature, with no molecular template and no organic contaminants. High-quality metal oxide semiconductor, photovoltaic and optoelectronic materials can be fabricated with nanometer-scale dimensions and high dopant densities through the use of low-temperature biologically inspired synthesis routes, without the use of any biological or biochemical templates.

Procedures and practices for evaluating thin-film solar cell stability

NARCIS (Netherlands)

Roesch, R; Faber, T; von Hauff, E.L.; Brown, T. M.; Lira-Cantu, M.; Hoppe, H.

2015-01-01

During the last few decades, and in some cases only the last few years, novel thin-film photovoltaic (PV) technologies such as dye-sensitized solar cells (DSSC), organic solar cells (OPV), and, more recently, perovskite-based solar cells (PSC) have been growing in maturity with respect to device

Machine Vision based Micro-crack Inspection in Thin-film Solar Cell Panel

Directory of Open Access Journals (Sweden)

Zhang Yinong

2014-09-01

Full Text Available Thin film solar cell consists of various layers so the surface of solar cell shows heterogeneous textures. Because of this property the visual inspection of micro-crack is very difficult. In this paper, we propose the machine vision-based micro-crack detection scheme for thin film solar cell panel. In the proposed method, the crack edge detection is based on the application of diagonal-kernel and cross-kernel in parallel. Experimental results show that the proposed method has better performance of micro-crack detection than conventional anisotropic model based methods on a cross- kernel.

Progress in thin-film silicon solar cells based on photonic-crystal structures

Science.gov (United States)

Ishizaki, Kenji; De Zoysa, Menaka; Tanaka, Yoshinori; Jeon, Seung-Woo; Noda, Susumu

2018-06-01

We review the recent progress in thin-film silicon solar cells with photonic crystals, where absorption enhancement is achieved by using large-area resonant effects in photonic crystals. First, a definitive guideline for enhancing light absorption in a wide wavelength range (600–1100 nm) is introduced, showing that the formation of multiple band edges utilizing higher-order modes confined in the thickness direction and the introduction of photonic superlattice structures enable significant absorption enhancement, exceeding that observed for conventional random scatterers. Subsequently, experimental evidence of this enhancement is demonstrated for a variety of thin-film Si solar cells: ∼500-nm-thick ultrathin microcrystalline silicon cells, few-µm-thick microcrystalline silicon cells, and ∼20-µm-thick thin single-crystalline silicon cells. The high short-circuit current densities and/or efficiencies observed for each cell structure confirm the effectiveness of using multiple band-edge resonant modes of photonic crystals for enhancing broadband absorption in actual solar cells.

Study of thin metal films and oxide materials for nanoelectronics applications

OpenAIRE

De Los Santos Valladares, Luis

2012-01-01

Appendix A Pages 132-134 have been removed from this online version of the thesis for publisher copyright reasons. These had contained page images from the cover of Nanotechnology, Vol. 21, Nov 2010 and its corresponding web alert Different types of thin metal films and oxide materials are studied for their potential application in nanoelectronics: gold and copper films, nickel nanoelectrodes, oxide nanograin superconductors, carboxyl ferromagnetic microspheres and graphene oxide...

Flexible Cu(In,Ga)Se2 thin-film solar cells for space application

International Nuclear Information System (INIS)

Otte, Karsten; Makhova, Liudmila; Braun, Alexander; Konovalov, Igor

2006-01-01

Thin film solar cells (TFSC) with Cu(In,Ga)Se 2 (CIGS) as absorber layer have been produced on rigid glass substrates for the terrestrial market. There exist, however, different investigations for manufacturing of TFSC on flexible substrates in order to achieve very thin and highly flexible (rollable) solar cells. Besides their capability to open new terrestrial market segments, they are considered as competitive candidates for future flexible thin film space power generators compared to traditional crystalline solar cells. This paper explains the advantages of flexible TFSC for usage in space, including:-low mass and storage volume, -high power/mass ratio [>100 W/kg at array level], -high radiation resistance against proton and electron radiation and, -lower production costs. These cells can be produced on flexible conductive and insulating substrate materials and have efficiency potentials of up to 15%. We report on the current development steps to adopt the TFSC technology to space requirements as well as the first European industrial approach to the roll-to-roll production of flexible CIGS-TFSC on polyimide as substrate material. Stability issues in space environment concern not only the TFSC itself, but all system components such as interconnects, cell assembly and flexible blankets. The adhesion of the back-contact to the substrate, the emissivity control in the infrared wavelength range, the electrical contacting and interconnection as well as flexible encapsulation are currently under investigation and are discussed in the paper. The production costs for TFSC for space application can be further reduced by sharing resources for the production of flexible TFSC for the terrestrial market; namely by using both, the existing terrestrial investment in production facilities as well as the synergies in R and D

Effects of accelerated degradation on metal supported thin film-based solid oxide fuel cell

DEFF Research Database (Denmark)

Reolon, R. P.; Sanna, S.; Xu, Yu

2018-01-01

A thin film-based solid oxide fuel cell is deposited on a Ni-based metal porous support by pulsed laser deposition with a multi-scale-graded microstructure design. The fuel cell, around 1 μm in thickness, is composed of a stabilized-zirconia/doped-ceria bi-layered dense electrolyte and nanostruct......A thin film-based solid oxide fuel cell is deposited on a Ni-based metal porous support by pulsed laser deposition with a multi-scale-graded microstructure design. The fuel cell, around 1 μm in thickness, is composed of a stabilized-zirconia/doped-ceria bi-layered dense electrolyte......, electrochemical performances are steady, indicating the stability of the cell. Under electrical load, a progressive degradation is activated. Post-test analysis reveals both mechanical and chemical degradation of the cell. Cracks and delamination of the thin films promote a significant nickel diffusion and new...

Porous Zinc Oxide Thin Films: Synthesis Approaches and Applications

Directory of Open Access Journals (Sweden)

Marco Laurenti

2018-02-01

Full Text Available Zinc oxide (ZnO thin films have been widely investigated due to their multifunctional properties, i.e., catalytic, semiconducting and optical. They have found practical use in a wide number of application fields. However, the presence of a compact micro/nanostructure has often limited the resulting material properties. Moreover, with the advent of low-dimensional ZnO nanostructures featuring unique physical and chemical properties, the interest in studying ZnO thin films diminished more and more. Therefore, the possibility to combine at the same time the advantages of thin-film based synthesis technologies together with a high surface area and a porous structure might represent a powerful solution to prepare ZnO thin films with unprecedented physical and chemical characteristics that may find use in novel application fields. Within this scope, this review offers an overview on the most successful synthesis methods that are able to produce ZnO thin films with both framework and textural porosities. Moreover, we discuss the related applications, mainly focused on photocatalytic degradation of dyes, gas sensor fabrication and photoanodes for dye-sensitized solar cells.

Sol–gel derived scattering layers as substrates for thin-film photovoltaic cells

Energy Technology Data Exchange (ETDEWEB)

Hegmann, Jan [Lehrstuhl für Chemische Technologie der Materialsynthese, Universität Würzburg, Röntgenring 11, 97070 Würzburg (Germany); Mandl, Magdalena [Fraunhofer-Institut für Silicatforschung, Neunerplatz 2, 97082 Würzburg (Germany); Löbmann, Peer, E-mail: peer.loebmann@isc.fraunhofer.de [Fraunhofer-Institut für Silicatforschung, Neunerplatz 2, 97082 Würzburg (Germany)

2014-08-01

Agglomerated silica particles were coated on glass by dip-coating; the resulting films exhibited optical scattering. With constant optical transmittances > 80% their haze could be modified by the withdrawal rate applied for the respective deposition procedure. Film thickness, surface topography and coverage of the substrate were characterized by Scanning Electron Microscopy and Atomic Force Microscopy. For the use in radiation management in thin-film silicon solar cells in a first step the scattering layers were coated with aluminum-doped zinc oxide by sputtering; the optical performance of the resulting bilayer was characterized by haze measurements and angle resolved scattering spectroscopy. Quantum efficiencies of complete solar cells could be determined after the deposition of a hydrogenated amorphous Si/hydrogenated microcrystalline Si tandem absorber and application of metallic back contacts. It turned out that the external quantum efficiency of the resulting cells is not directly related to the light scattering performance of the scattering layer used. - Highlights: • Characterization of sol–gel scattering layers • Combination of different coating-technologies to prepare stacks with optical functionality • Comprehensive material preparation and characterization for complex multilayer.

Structural and biocompatible characterization of TiC/a:C nanocomposite thin films

International Nuclear Information System (INIS)

Balázsi, K.; Vandrovcová, M.; Bačáková, L.; Balázsi, Cs.

2013-01-01

In this work, sputtered TiC/amorphous C thin films have been developed in order to be applied as potential barrier coating for interfering of Ti ions from pure Ti or Ti alloy implants. Our experiments were based on magnetron sputtering method, because the vacuum deposition provides great flexibility for manipulating material chemistry and structure, leading to films and coatings with special properties. The films have been deposited on silicon (001) substrates with 300 nm thick oxidized silicon sublayer at 200 °C deposition temperature as model substrate. Transmission electron microscopy has been used for structural investigations. Thin films consisted of ∼ 20 nm TiC columnar crystals embedded by 5 nm thin amorphous carbon matrix. MG63 osteoblast cells have been applied for in vitro study of TiC nanocomposites. The cell culture tests give strong evidence of thin films biocompatibility. Highlights: ► The main goal of this work is the relatively easy preparation of nanocomposite TiC thin films by dc magnetron sputtering. ► TEM and HREM were applied for structural characterization of columnar TiC nanocrystals and amorphous carbon matrix. ► The biocompatibility of films was showed by MG63 human osteoblast like cells during 1, 3 and 7 days seeding

Temperature Effects on a-IGZO Thin Film Transistors Using HfO2 Gate Dielectric Material

OpenAIRE

Lin, Yu-Hsien; Chou, Jay-Chi

2014-01-01

This study investigated the temperature effect on amorphous indium gallium zinc oxide (a-IGZO) thin film transistors (TFTs) using hafnium oxide (HfO2) gate dielectric material. HfO2 is an attractive candidate as a high-κ dielectric material for gate oxide because it has great potential to exhibit superior electrical properties with a high drive current. In the process of integrating the gate dielectric and IGZO thin film, postannealing treatment is an essential process for completing the chem...

On-Orbit Demonstration of a Lithium-Ion Capacitor and Thin-Film Multijunction Solar Cells

Science.gov (United States)

Kukita, Akio; Takahashi, Masato; Shimazaki, Kazunori; Kobayashi, Yuki; Sakai, Tomohiko; Toyota, Hiroyuki; Takahashi, Yu; Murashima, Mio; Uno, Masatoshi; Imaizumi, Mitsuru

2014-08-01

This paper describes an on-orbit demonstration of the Next-generation Small Satellite Instrument for Electric power systems (NESSIE) on which an aluminum- laminated lithium-ion capacitor (LIC) and a lightweight solar panel called KKM-PNL, which has space solar sheets using thin-film multijunction solar cells, were installed. The flight data examined in this paper covers a period of 143 days from launch. We verified the integrity of an LIC constructed using a simple and lightweight mounting method: no significant capacitance reduction was observed. We also confirmed that inverted metamorphic multijunction triple-junction thin-film solar cells used for evaluation were healthy at 143 days after launch, because their degradation almost matched the degradation predictions for dual-junction thin-film solar cells.

Laser Welding of Silicon Foils for Thin-Film Solar Cell Manufacturing

OpenAIRE

Heßmann, Maik

2014-01-01

Thin-film solar module manufacturing is one of the most promising recent developments in photovoltaic research and has the potential to reduce production costs. As the necessity for competitive prices on the world market increases and manufacturers endeavor to bring down the cost of solar modules, thin-film technology is becoming more and more attractive. In this work a special technique was investigated which makes solar cell manufacturing more compatible with an industrial roll-to-roll proc...

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.

Cu2ZnSnSe4 Thin Film Solar Cell with Depth Gradient Composition Prepared by Selenization of Sputtered Novel Precursors.

Science.gov (United States)

Lai, Fang-I; Yang, Jui-Fu; Chen, Wei-Chun; Kuo, Shou-Yi

2017-11-22

In this study, we proposed a new method for the synthesis of the target material used in a two stage process for preparation of a high quality CZTSe thin film. The target material consisting of a mixture of Cu x Se and Zn x Sn 1-x alloy was synthesized, providing a quality CZTSe precursor layer for highly efficient CZTSe thin film solar cells. The CZTSe thin film can be obtained by annealing the precursor layers through a 30 min selenization process under a selenium atmosphere at 550 °C. The CZTSe thin films prepared by using the new precursor thin film were investigated and characterized using X-ray diffraction, Raman scattering, and photoluminescence spectroscopy. It was found that diffusion of Sn occurred and formed the CTSe phase and Cu x Se phase in the resultant CZTSe thin film. By selective area electron diffraction transmission electron microscopy images, the crystallinity of the CZTSe thin film was verified to be single crystal. By secondary ion mass spectroscopy measurements, it was confirmed that a double-gradient band gap profile across the CZTSe absorber layer was successfully achieved. The CZTSe solar cell with the CZTSe absorber layer consisting of the precursor stack exhibited a high efficiency of 5.46%, high short circuit current (J SC ) of 37.47 mA/cm 2 , open circuit voltage (V OC ) of 0.31 V, and fill factor (F.F.) of 47%, at a device area of 0.28 cm 2 . No crossover of the light and dark current-voltage (I-V) curves of the CZTSe solar cell was observed, and also, no red kink was observed under red light illumination, indicating a low defect concentration in the CZTSe absorber layer. Shunt leakage current with a characteristic metal/CZTSe/metal leakage current model was observed by temperature-dependent I-V curves, which led to the discovery of metal incursion through the CdS buffer layer on the CZTSe absorber layer. This leakage current, also known as space charge-limited current, grew larger as the measurement temperature increased and

Band gap engineering of hydrogenated amorphous carbon thin films for solar cell application

Science.gov (United States)

Dwivedi, Neeraj; Kumar, Sushil; Dayal, Saurabh; Rauthan, C. M. S.; Panwar, O. S.; Malik, Hitendra K.

2012-10-01

In this work, self bias variation, nitrogen introduction and oxygen plasma (OP) treatment approaches have been used for tailoring the band gap of hydrogenated amorphous carbon (a-C:H) thin films. The band gap of a-C:H and modified a- C:H films is varied in the range from 1.25 eV to 3.45 eV, which is found to be nearly equal to the full solar spectrum (1 eV- 3.5 eV). Hence, such a-C:H and modified a-C:H films are found to be potential candidate for the development of full spectrum solar cells. Besides this, computer aided simulation with considering variable band gap a-C:H and modified a- C:H films as window layer for amorphous silicon p-i-n solar cells is also performed by AFORS-HET software and maximum efficiency as ~14 % is realized. Since a-C:H is hard material, hence a-C:H and modified a-C:H films as window layer may avoid the use of additional hard and protective coating particularly in n-i-p configuration.

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

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.

Optical fiber magnetic field sensors with TbDyFe magnetostrictive thin films as sensing materials.

Science.gov (United States)

Yang, Minghong; Dai, Jixiang; Zhou, Ciming; Jiang, Desheng

2009-11-09

Different from usually-used bulk magnetostrictive materials, magnetostrictive TbDyFe thin films were firstly proposed as sensing materials for fiber-optic magnetic field sensing characterization. By magnetron sputtering process, TbDyFe thin films were deposited on etched side circle of a fiber Bragg Grating (FBG) as sensing element. There exists more than 45pm change of FBG wavelength when magnet field increase up to 50 mT. The response to magnetic field is reversible, and could be applicable for magnetic and current sensing.

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

Control method and system for use when growing thin-films on semiconductor-based materials

Science.gov (United States)

McKee, Rodney A.; Walker, Frederick J.

2001-01-01

A process and system for use during the growth of a thin film upon the surface of a substrate by exposing the substrate surface to vaporized material in a high vacuum (HV) facility involves the directing of an electron beam generally toward the surface of the substrate as the substrate is exposed to vaporized material so that electrons are diffracted from the substrate surface by the beam and the monitoring of the pattern of electrons diffracted from the substrate surface as vaporized material settles upon the substrate surface. When the monitored pattern achieves a condition indicative of the desired condition of the thin film being grown upon the substrate, the exposure of the substrate to the vaporized materials is shut off or otherwise adjusted. To facilitate the adjustment of the crystallographic orientation of the film relative to the electron beam, the system includes a mechanism for altering the orientation of the surface of the substrate relative to the electron beam.

Cytotoxicity Evaluation of Anatase and Rutile TiO2 Thin Films on CHO-K1 Cells in Vitro

Directory of Open Access Journals (Sweden)

Blanca Cervantes

2016-07-01

Full Text Available Cytotoxicity of titanium dioxide (TiO2 thin films on Chinese hamster ovary (CHO-K1 cells was evaluated after 24, 48 and 72 h of culture. The TiO2 thin films were deposited using direct current magnetron sputtering. These films were post-deposition annealed at different temperatures (300, 500 and 800 °C toward the anatase to rutile phase transformation. The root-mean-square (RMS surface roughness of TiO2 films went from 2.8 to 8.08 nm when the annealing temperature was increased from 300 to 800 °C. Field emission scanning electron microscopy (FESEM results showed that the TiO2 films’ thickness values fell within the nanometer range (290–310 nm. Based on the results of the tetrazolium dye and trypan blue assays, we found that TiO2 thin films showed no cytotoxicity after the aforementioned culture times at which cell viability was greater than 98%. Independently of the annealing temperature of the TiO2 thin films, the number of CHO-K1 cells on the control substrate and on all TiO2 thin films was greater after 48 or 72 h than it was after 24 h; the highest cell survival rate was observed in TiO2 films annealed at 800 °C. These results indicate that TiO2 thin films do not affect mitochondrial function and proliferation of CHO-K1 cells, and back up the use of TiO2 thin films in biomedical science.

Cytotoxicity Evaluation of Anatase and Rutile TiO2 Thin Films on CHO-K1 Cells in Vitro

Science.gov (United States)

Cervantes, Blanca; López-Huerta, Francisco; Vega, Rosario; Hernández-Torres, Julián; García-González, Leandro; Salceda, Emilio; Herrera-May, Agustín L.; Soto, Enrique

2016-01-01

Cytotoxicity of titanium dioxide (TiO2) thin films on Chinese hamster ovary (CHO-K1) cells was evaluated after 24, 48 and 72 h of culture. The TiO2 thin films were deposited using direct current magnetron sputtering. These films were post-deposition annealed at different temperatures (300, 500 and 800 °C) toward the anatase to rutile phase transformation. The root-mean-square (RMS) surface roughness of TiO2 films went from 2.8 to 8.08 nm when the annealing temperature was increased from 300 to 800 °C. Field emission scanning electron microscopy (FESEM) results showed that the TiO2 films’ thickness values fell within the nanometer range (290–310 nm). Based on the results of the tetrazolium dye and trypan blue assays, we found that TiO2 thin films showed no cytotoxicity after the aforementioned culture times at which cell viability was greater than 98%. Independently of the annealing temperature of the TiO2 thin films, the number of CHO-K1 cells on the control substrate and on all TiO2 thin films was greater after 48 or 72 h than it was after 24 h; the highest cell survival rate was observed in TiO2 films annealed at 800 °C. These results indicate that TiO2 thin films do not affect mitochondrial function and proliferation of CHO-K1 cells, and back up the use of TiO2 thin films in biomedical science. PMID:28773740

Non-toxic and environmentally friendly route for preparation of copper indium sulfide based thin film solar cells

Energy Technology Data Exchange (ETDEWEB)

Sankir, Nurdan Demirci, E-mail: nsankir@etu.edu.tr; Aydin, Erkan; Ugur, Esma; Sankir, Mehmet

2015-08-15

Highlights: • Substrate structure of spray pyrolyzed CuInS{sub 2}/In{sub 2}S{sub 3} heterojunction solar cells. • Low cost and environmentally friendly fabrication of CuInS{sub 2} based solar cells. • Low RF power deposition of TCO layer. • AZO–Ag–AZO sandwich structure. • Effect of the thickness of buffer layer on the photovoltaic performance. - Abstract: In this study, copper based thin film solar cells with substrate structure have been built via spray pyrolysis method. Toxic material usage was avoided during the material deposition and the post-treatment steps. Novel device configuration of Mo/CuInS{sub 2}/In{sub 2}S{sub 3}/ZnO/AZO–Ag–AZO was studied as a function of the In{sub 2}S{sub 3} buffer layer thickness. In order to utilize the zinc oxide (ZnO) and aluminum doped zinc oxide (AZO) transparent conductive layers, deposited by physical vapor deposition (PVD), on top of the spray pyrolyzed thin films, the RF power was lowered to 30 W. Although this minimized the unwanted penetration of the highly energetic particles, created during PVD process, sheet resistivity of the AZO films increased enormously. Hence very thin silver layer has been deposited between two AZO films. This resulted the decrease in the sheet resistivity more than 10{sup 6} times. Electrical measurements under illumination revealed that short circuit current density (J{sub sc}), open circuit voltage (V{sub oc}), fill factor (FF) and efficiency (η) of the Mo/CuInS{sub 2}/In{sub 2}S{sub 3}/ZnO/AZO–Ag–AZO type solar cells increased with increasing the thickness of the In{sub 2}S{sub 3} layer. The maximum J{sub sc} of 9.20 mA/cm{sup 2}, V{sub oc} of 0.43 V, FF of 0.44 have been observed for the 0.94 μm-thick In{sub 2}S{sub 3} layer. Extraordinarily thick buffer layer provided better diffusion barrier between the absorber and the TCO layers and also resulted better photosensitivity. These could be the key factors to produce substrate configuration of the spray pyrolyzed

Optical characterization of a-Si:H thin films grown by Hg-Photo-CVD

International Nuclear Information System (INIS)

Barhdadi, A.; Karbal, S.; M'Gafad, N.; Benmakhlouf, A.; Chafik El Idrissi, M.; Aka, B.M.

2006-08-01

Mercury-Sensitized Photo-Assisted Chemical Vapor Deposition (Hg-Photo-CVD) technique opens new possibilities for reducing thin film growth temperature and producing novel semiconductor materials suitable for the future generation of high efficiency thin film solar cells onto low cost flexible plastic substrates. This paper provides some experimental data resulting from the optical characterization of hydrogenated amorphous silicon thin films grown by this deposition technique. Experiments have been performed on both as-deposited layers and thermal annealed ones. (author) [fr

Comparative alternative materials assessment to screen toxicity hazards in the life cycle of CIGS thin film photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Eisenberg, Daniel A.; Yu, Mengjing; Lam, Carl W. [University of California, Davis, 1 Shields Avenue, Davis, CA 95616 (United States); Ogunseitan, Oladele A. [University of California, Irvine, Irvine, CA 92697 (United States); Schoenung, Julie M., E-mail: jmschoenung@ucdavis.edu [University of California, Davis, 1 Shields Avenue, Davis, CA 95616 (United States)

2013-09-15

Highlights: • Comparative alternatives assessment of thin film manufacturing technologies. • Development of chemical alternatives assessment in a life cycle context. • Screening of manufacturing and solar cell hazardous substances simultaneously. -- Abstract: Copper–indium–gallium–selenium–sulfide (CIGS) thin film photovoltaics are increasingly penetrating the market supply for consumer solar panels. Although CIGS is attractive for producing less greenhouse gas emissions than fossil-fuel based energy sources, CIGS manufacturing processes and solar cell devices use hazardous materials that should be carefully considered in evaluating and comparing net environmental benefits of energy products. Through this research, we present a case study on the toxicity hazards associated with alternative materials selection for CIGS manufacturing. We applied two numeric models, The Green Screen for Safer Chemicals™ and the Toxic Potential Indicator. To improve the sensitivity of the model outputs, we developed a novel, life cycle thinking based hazard assessment method that facilitates the projection of hazards throughout material life cycles. Our results show that the least hazardous CIGS solar cell device and manufacturing protocol consist of a titanium substrate, molybdenum metal back electrode, CuInS{sub 2} p-type absorber deposited by spray pyrolysis, ZnS buffer deposited by spray ion layer gas reduction, ZnO:Ga transparent conducting oxide (TCO) deposited by sputtering, and the encapsulant polydimethylsiloxane.

Optimized flexible cover films for improved conversion efficiency in thin film flexible solar cells

Science.gov (United States)

Guterman, Sidney; Wen, Xin; Gudavalli, Ganesh; Rhajbhandari, Pravakar; Dhakal, Tara P.; Wilt, David; Klotzkin, David

2018-05-01

Thin film solar cell technologies are being developed for lower cost and flexible applications. For such technologies, it is desirable to have inexpensive, flexible cover strips. In this paper, we demonstrate that transparent silicone cover glass adhesive can be doped with TiO2 nanoparticles to achieve an optimal refractive index and maximize the performance of the cell. Cells covered with the film doped with nanoparticles at the optimal concentration demonstrated a ∼1% increase in photocurrent over the plain (undoped) film. In addition, fused silica beads can be incorporated into the flexible cover slip to realize a built-in pseudomorphic glass diffuser layer as well. This additional degree of freedom in engineering flexible solar cell covers allows maximal performance from a given cell for minimal increased cost.

Complementarities of nuclear-based analytical techniques for the characterization of thin film technological materials

International Nuclear Information System (INIS)

Bamford, Samuel; Kregsamer, Peter; Fazinic, Stjepko; Jaksic, Milko; Wegrzynek, Dariusz; Chinea-Cano, Ernesto; Markowicz, Andrzej

2007-01-01

Two thin film technological materials (A/B) from the aerospace industry have been characterized for their elemental composition, for the purpose of determining their purity and trace element distribution. The results contribute to the assessment of the materials' suitability as part of a spacecraft's thermal hardware. Analysis was done using a combination of PIXE/RBS and energy dispersive X-ray fluorescence (EDXRF) analytical techniques. Samples of the materials were analyzed with PIXE/RBS system using 2 MeV proton beam from a 1 MV Tandetron accelerator and also with separate EDXRF systems employing Am-241 and Mo-secondary target as excitation sources. PIXE/RBS measurements enabled identification of the elemental composition and elucidation of the layer structure of the materials. From the PIXE/RBS results, Am-241-excited EDXRF technique was selected for quantitative determination of indium (In) and tin (Sn) by their K-X-rays, after reasonable absorption corrections. A comparison has been made of the results obtained from EDXRF and PIXE/RBS. Material A has been found to be a thin film with three layers, while material B is a thin film comprised of four layers. Thicknesses and compositions (including trace elements) of all layers have been determined. The limitation of EDXRF in the analysis of inhomogeneously distributed elements was overcome by using PIXE/RBS as an appropriate complimentary technique

Large-area SnO2: F thin films by offline APCVD

International Nuclear Information System (INIS)

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

2011-01-01

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

Physical vapor deposition of CdTe thin films at low temperature for solar cell applications

Energy Technology Data Exchange (ETDEWEB)

Heisler, Christoph; Brueckner, Michael; Lind, Felix; Kraft, Christian; Reisloehner, Udo; Ronning, Carsten; Wesch, Werner [Institute of Solid State Physics, University of Jena, Max-Wien-Platz 1, D-07743 Jena (Germany)

2012-07-01

Cadmium telluride is successfully utilized as an absorber material for thin film solar cells. Industrial production makes use of high substrate temperatures for the deposition of CdTe absorber layers. However, in order to exploit flexible substrates and to simplify the manufacturing process, lower deposition temperatures are beneficial. Based on the phase diagram of CdTe, predictions on the stoichiometry of CdTe thin films grown at low substrate temperatures are made in this work. These predictions were verified experimentally using additional sources of Cd and Te during the deposition of the CdTe thin films at different substrate temperatures. The deposited layers were analyzed with energy-dispersive X-ray spectroscopy. In case of CdTe layers which were deposited at substrate temperatures lower than 200 C without usage of additional sources we found a non-stoichiometric growth of the CdTe layers. The application of the additional sources leads to a stoichiometric growth for substrate temperatures down to 100 C which is a significant reduction of the substrate temperature during deposition.

Thin film heterojunction photovoltaic cells and methods of making the same

Science.gov (United States)

Basol, Bulent M.; Tseng, Eric S.; Rod, Robert L.

1983-06-14

A method of fabricating a thin film heterojunction photovoltaic cell which comprises depositing a film of a near intrinsic or n-type semiconductor compound formed of at least one of the metal elements of Class II B of the Periodic Table of Elements and at least tellurium and then heating said film at a temperature between about 250.degree. C. and 500.degree. C. for a time sufficient to convert said film to a suitably low resistivity p-type semiconductor compound. Such film may be deposited initially on the surface of an n-type semiconductor substrate. Alternatively, there may be deposited on the converted film a layer of n-type semiconductor compound different from the film semiconductor compound. The resulting photovoltaic cell exhibits a substantially increased power output over similar cells not subjected to the method of the present invention.

Thin film battery/fuel cell power generating system. Final report, Task E-4, April 1976-April 1978

Energy Technology Data Exchange (ETDEWEB)

Feduska, W.

1978-03-31

A two-year researth program to design and demonstrate the technical feasibility of a high-temperature solid-electrolyte fuel cell is described in detail. A rare-earth chromite, in particular, La /sub 95/Mg /sub 05/Cr /sub 75/Al /sub 25/0/sub 3/ was identified, synthesized by RF-sputtering tested for resistivity, thermal expansion and inertness in contact with yttria-stabilized zirconia, and was found promising as a candidate interconnection material. Films of these interconnection materials have been successfully deposited onto stabilized zirconia tubes by electrochemical vapor deposition (EVD) and the technique has been used to fabricate such films in building fuel cell stacks. Tin-doped indium oxide and antimony-doped tin oxide air electrode current collector materials have been successfully (CVD) chemically vapor deposited, as thin films, onto zirconia tubes. Fabrication procedures for the preparation of thin films of the nickel-cermet fuel electrode and yttria-stabilized zirconia solid electrolyte have been re-verified and improved for use in preparing unit cells and cell stacks on the program. An in-house extrusion technology for porous calcia-stabilized zirconia tubes has been developed and has been used to provide suitable support tubes for component combination samples, unit cell and cell stack sample preparation. Test concepts for component combinations and for unit cells and cell stacks have been evolved, particularly, the crossed electrode technique, and test equipment has been designed, built and used to evaluate fuel cell components and their interfaces. A five-cell fuel cell stack has been fabricated and operated for 700 hours at 200 mA/cm/sup 2/ at 950 to 980/sup 0/C and was subjected to three temperature cycles during the testing. Three series connected cells of this five cell stack met the 80% voltage efficiency final target objective of the program (less than 10% voltage degradation in 700 hours - with only 300 hours required.)

High Efficiency Thin Film CdTe and a-Si Based Solar Cells: Final Technical Report, 4 March 1998--15 October 2001

Energy Technology Data Exchange (ETDEWEB)

Compaan, A. D.; Deng, X.; Bohn, R. G.

2003-10-01

This is the final report covering about 42 months of this subcontract for research on high-efficiency CdTe-based thin-film solar cells and on high-efficiency a-Si-based thin-film solar cells. Phases I and II have been extensively covered in two Annual Reports. For this Final Report, highlights of the first two Phases will be provided and then detail will be given on the last year and a half of Phase III. The effort on CdTe-based materials is led by Prof. Compaan and emphasizes the use of sputter deposition of the semiconductor layers in the fabrication of CdS/CdTe cells. The effort on high-efficiency a-Si materials is led by Prof. Deng and emphasizes plasma-enhanced chemical vapor deposition for cell fabrication with major efforts on triple-junction devices.

Nanocomposite C-Pd thin films – a new material with specific spectral properties

Directory of Open Access Journals (Sweden)

M. Suchańska

2013-09-01

Full Text Available In this paper, the results of optical investigations for thin films of carbon-palladium (C-Pd nanocomposites are presented. This films were prepared using two steps method (PVD/ CVD. The optical and Raman spectroscopy has been used to characterize the material. The multinanolayer model was used to explain the specific spectral properties.

Flush Mounting Of Thin-Film Sensors

Science.gov (United States)

Moore, Thomas C., Sr.

1992-01-01

Technique developed for mounting thin-film sensors flush with surfaces like aerodynamic surfaces of aircraft, which often have compound curvatures. Sensor mounted in recess by use of vacuum pad and materials selected for specific application. Technique involves use of materials tailored to thermal properties of substrate in which sensor mounted. Together with customized materials, enables flush mounting of thin-film sensors in most situations in which recesses for sensors provided. Useful in both aircraft and automotive industries.

Influence of Cu–Ti thin film surface properties on antimicrobial activity and viability of living cells

International Nuclear Information System (INIS)

Wojcieszak, Damian; Kaczmarek, Danuta; Antosiak, Aleksandra; Mazur, Michal; Rybak, Zbigniew; Rusak, Agnieszka; Osekowska, Malgorzata; Poniedzialek, Agata; Gamian, Andrzej; Szponar, Bogumila

2015-01-01

The paper describes properties of thin-film coatings based on copper and titanium. Thin films were prepared by co-sputtering of Cu and Ti targets in argon plasma. Deposited coatings consist of 90 at.% of Cu and 10 at.% of Ti. Characterization of the film was made on the basis of investigations of microstructure and physicochemical properties of the surface. Methods such as scanning electron microscopy, x-ray microanalysis, x-ray diffraction, x-ray photoelectron spectroscopy, atomic force microscopy, optical profilometry and wettability measurements were used to assess the properties of deposited thin films. An impact of Cu–Ti coating on the growth of selected bacteria and viability of the living cells (line L929, NCTC clone 929) was described in relation to the structure, surface state and wettability of the film. It was found that as-deposited films were amorphous. However, in such surroundings the nanocrystalline grains of 10–15 nm and 25–35 nm size were present. High surface active area with a roughness of 8.9 nm, had an effect on receiving relatively high water contact angle value (74.1°). Such wettability may promote cell adhesion and result in an increase of the probability of copper ion transfer from the film surface into the cell. Thin films revealed bactericidal and fungicidal effects even in short term-contact. High activity of prepared films was directly related to high amount (ca. 51 %) of copper ions at 1+ state as x-ray photoelectron spectroscopy results have shown. - Graphical abstract: Bactericidal and fungicidal effects of time contact with surface of Cu–Ti thin films. - Highlights: • Antimicrobial activity and cytotoxic effect (viability of L929 cell line) of metallic Cu–Ti films • Thin films were prepared by co-sputtering of Cu and Ti. • As-deposited Cu–Ti films were amorphous and homogenous. • Bactericidal and fungicidal effects even in short term-contact were observed

Influence of Cu–Ti thin film surface properties on antimicrobial activity and viability of living cells

Energy Technology Data Exchange (ETDEWEB)

Wojcieszak, Damian, E-mail: damian.wojcieszak@pwr.edu.pl [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Kaczmarek, Danuta [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Antosiak, Aleksandra [Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla 12, 53-114 Wrocław (Poland); Mazur, Michal [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Rybak, Zbigniew; Rusak, Agnieszka; Osekowska, Malgorzata [Department for Experimental Surgery and Biomaterials Research, Wroclaw Medical University, Poniatowskiego 2, 50-326 Wroclaw (Poland); Poniedzialek, Agata [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Gamian, Andrzej; Szponar, Bogumila [Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla 12, 53-114 Wrocław (Poland)

2015-11-01

The paper describes properties of thin-film coatings based on copper and titanium. Thin films were prepared by co-sputtering of Cu and Ti targets in argon plasma. Deposited coatings consist of 90 at.% of Cu and 10 at.% of Ti. Characterization of the film was made on the basis of investigations of microstructure and physicochemical properties of the surface. Methods such as scanning electron microscopy, x-ray microanalysis, x-ray diffraction, x-ray photoelectron spectroscopy, atomic force microscopy, optical profilometry and wettability measurements were used to assess the properties of deposited thin films. An impact of Cu–Ti coating on the growth of selected bacteria and viability of the living cells (line L929, NCTC clone 929) was described in relation to the structure, surface state and wettability of the film. It was found that as-deposited films were amorphous. However, in such surroundings the nanocrystalline grains of 10–15 nm and 25–35 nm size were present. High surface active area with a roughness of 8.9 nm, had an effect on receiving relatively high water contact angle value (74.1°). Such wettability may promote cell adhesion and result in an increase of the probability of copper ion transfer from the film surface into the cell. Thin films revealed bactericidal and fungicidal effects even in short term-contact. High activity of prepared films was directly related to high amount (ca. 51 %) of copper ions at 1+ state as x-ray photoelectron spectroscopy results have shown. - Graphical abstract: Bactericidal and fungicidal effects of time contact with surface of Cu–Ti thin films. - Highlights: • Antimicrobial activity and cytotoxic effect (viability of L929 cell line) of metallic Cu–Ti films • Thin films were prepared by co-sputtering of Cu and Ti. • As-deposited Cu–Ti films were amorphous and homogenous. • Bactericidal and fungicidal effects even in short term-contact were observed.

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.

ZnO transparent conductive oxide for thin film silicon solar cells

Science.gov (United States)

Söderström, T.; Dominé, D.; Feltrin, A.; Despeisse, M.; Meillaud, F.; Bugnon, G.; Boccard, M.; Cuony, P.; Haug, F.-J.; Faÿ, S.; Nicolay, S.; Ballif, C.

2010-03-01

There is general agreement that the future production of electric energy has to be renewable and sustainable in the long term. Photovoltaic (PV) is booming with more than 7GW produced in 2008 and will therefore play an important role in the future electricity supply mix. Currently, crystalline silicon (c-Si) dominates the market with a share of about 90%. Reducing the cost per watt peak and energy pay back time of PV was the major concern of the last decade and remains the main challenge today. For that, thin film silicon solar cells has a strong potential because it allies the strength of c-Si (i.e. durability, abundancy, non toxicity) together with reduced material usage, lower temperature processes and monolithic interconnection. One of the technological key points is the transparent conductive oxide (TCO) used for front contact, barrier layer or intermediate reflector. In this paper, we report on the versatility of ZnO grown by low pressure chemical vapor deposition (ZnO LP-CVD) and its application in thin film silicon solar cells. In particular, we focus on the transparency, the morphology of the textured surface and its effects on the light in-coupling for micromorph tandem cells in both the substrate (n-i-p) and superstrate (p-i-n) configurations. The stabilized efficiencies achieved in Neuchâtel are 11.2% and 9.8% for p-i-n (without ARC) and n-i-p (plastic substrate), respectively.

Alternative nano-structured thin-film materials used as durable thermal nanoimprint lithography templates

Science.gov (United States)

Bossard, M.; Boussey, J.; Le Drogoff, B.; Chaker, M.

2016-02-01

Nanoimprint templates made of diamond-like carbon (DLC) and amorphous silicon carbide (SiC) thin films and fluorine-doped associated materials, i.e. F-DLC and F-SiC were investigated in the context of thermal nanoimprint lithography (NIL) with respect to their release properties. Their performances in terms of durability and stability were evaluated and compared to those of conventional silicon or silica molds coated with antisticking molecules applied as a self-assembled monolayer. Plasma-enhanced chemical vapor deposition parameters were firstly tuned to optimize mechanical and structural properties of the DLC and SiC thin films. The impact of the amount of fluorine dopant on the deposited thin films properties was then analyzed. A comparative analysis of DLC, F-DLC as well as SiC and F-SiC molds was then carried out over multiple imprints, performed into poly (methyl methacrylate) (PMMA) thermo-plastic resist. The release properties of un-patterned films were evaluated by the measurement of demolding energies and surface energies, associated with a systematic analysis of the mold surface contamination. These analyses showed that the developed materials behave as intrinsically easy-demolding and contamination-free molds over series of up to 40 imprints. To our knowledge, it is the first time that such a large number of imprints has been considered within an exhaustive comparative study of materials for NIL. Finally, the developed materials went through standard e-beam lithography and plasma etching processes to obtain nanoscale-patterned templates. The replicas of those patterned molds, imprinted into PMMA, were shown to be of high fidelity and good stability after several imprints.

Effect of Annealing on the Properties of Antimony Telluride Thin Films and Their Applications in CdTe Solar Cells

Directory of Open Access Journals (Sweden)

Zhouling Wang

2014-01-01

Full Text Available Antimony telluride alloy thin films were deposited at room temperature by using the vacuum coevaporation method. The films were annealed at different temperatures in N2 ambient, and then the compositional, structural, and electrical properties of antimony telluride thin films were characterized by X-ray fluorescence, X-ray diffraction, differential thermal analysis, and Hall measurements. The results indicate that single phase antimony telluride existed when the annealing temperature was higher than 488 K. All thin films exhibited p-type conductivity with high carrier concentrations. Cell performance was greatly improved when the antimony telluride thin films were used as the back contact layer for CdTe thin film solar cells. The dark current voltage and capacitance voltage measurements were performed to investigate the formation of the back contacts for the cells with or without Sb2Te3 buffer layers. CdTe solar cells with the buffer layers can reduce the series resistance and eliminate the reverse junction between CdTe and metal electrodes.

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.

Self-assembled three-dimensional and compressible interdigitated thin-film supercapacitors and batteries

Science.gov (United States)

Nyström, Gustav; Marais, Andrew; Karabulut, Erdem; Wågberg, Lars; Cui, Yi; Hamedi, Mahiar M.

2015-01-01

Traditional thin-film energy-storage devices consist of stacked layers of active films on two-dimensional substrates and do not exploit the third dimension. Fully three-dimensional thin-film devices would allow energy storage in bulk materials with arbitrary form factors and with mechanical properties unique to bulk materials such as compressibility. Here we show three-dimensional energy-storage devices based on layer-by-layer self-assembly of interdigitated thin films on the surface of an open-cell aerogel substrate. We demonstrate a reversibly compressible three-dimensional supercapacitor with carbon nanotube electrodes and a three-dimensional hybrid battery with a copper hexacyanoferrate ion intercalating cathode and a carbon nanotube anode. The three-dimensional supercapacitor shows stable operation over 400 cycles with a capacitance of 25 F g−1 and is fully functional even at compressions up to 75%. Our results demonstrate that layer-by-layer self-assembly inside aerogels is a rapid, precise and scalable route for building high-surface-area 3D thin-film devices. PMID:26021485

Effect of cell thickness on the electrical and optical properties of thin film silicon solar cell

Science.gov (United States)

Zaki, A. A.; El-Amin, A. A.

2017-12-01

In this work Electrical and optical properties of silicon thin films with different thickness were measured. The thickness of the Si films varied from 100 to 800 μm. The optical properties of the cell were studied at different thickness. A maximum achievable current density (MACD) generated by a planar solar cell, was measured for different values of the cell thickness which was performed by using photovoltaic (PV) optics method. It was found that reducing the values of the cell thickness improves the open-circuit voltage (VOC) and the fill factor (FF) of the solar cell. The optical properties were measured for thin film Si (TF-Si) at different thickness by using the double beam UV-vis-NIR spectrophotometer in the wavelength range of 300-2000 nm. Some of optical parameters such as refractive index with dispersion relation, the dispersion energy, the oscillator energy, optical band gap energy were calculated by using the spectra for the TF-Si with different thickness.

Transparent sculptured titania films for enhanced light absorption in thin-film Si solar cells

Energy Technology Data Exchange (ETDEWEB)

Hung, Kai-Hsiang, E-mail: khhung@itri.org.tw [Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan (China); Chiou, Guan-Di; Wong, Ming-Show [Department of Materials Science and Engineering, National Dong Hwa University, Hualien, Taiwan (China); Wang, Yu-Chih [Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan (China); Chung, I-Shan [Electronics and Optoelectronics Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan (China)

2011-12-30

This study presents a description of the enhancement of light absorption in thin-film silicon (Si) solar cells by using sculptured titania (TiO{sub 2}) films. We used an electron-beam evaporation system with a glancing angle deposition (GLAD) method to deposit porous TiO{sub 2} films on fluorine-doped SnO{sub 2} (FTO) substrates. The GLAD TiO{sub 2}/FTO films were used as conductive electrodes in hydrogenated microcrystalline silicon ({mu}c-Si:H) solar cells. Transmission electron microscopy revealed that the GLAD TiO{sub 2} films are composed of sculptured nano-pillars on an FTO surface, and this nanostructure provides a synergistic route for light scattering enhancement. The GLAD TiO{sub 2}/FTO exhibited a 68% improvement of optical haze (at {lambda} = 600 nm). The {mu}c-Si:H solar cells consisting of the GLAD-nanostructured TiO{sub 2} resulted in a 5% improvement of short-circuit current (J{sub sc}) and yielded a cell efficiency of 6.6%.

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.

Effect of Grain Boundaries on the Performance of Thin-Film-Based Polycrystalline Silicon Solar Cells: A Numerical Modeling

Science.gov (United States)

Chhetri, Nikita; Chatterjee, Somenath

2018-01-01

Solar cells/photovoltaic, a renewable energy source, is appraised to be the most effective alternative to the conventional electrical energy generator. A cost-effective alternative of crystalline wafer-based solar cell is thin-film polycrystalline-based solar cell. This paper reports the numerical analysis of dependency of the solar cell parameters (i.e., efficiency, fill factor, open-circuit voltage and short-circuit current density) on grain size for thin-film-based polycrystalline silicon (Si) solar cells. A minority carrier lifetime model is proposed to do a correlation between the grains, grain boundaries and lifetime for thin-film-based polycrystalline Si solar cells in MATLAB environment. As observed, the increment in the grain size diameter results in increase in minority carrier lifetime in polycrystalline Si thin film. A non-equivalent series resistance double-diode model is used to find the dark as well as light (AM1.5) current-voltage (I-V) characteristics for thin-film-based polycrystalline Si solar cells. To optimize the effectiveness of the proposed model, a successive approximation method is used and the corresponding fitting parameters are obtained. The model is validated with the experimentally obtained results reported elsewhere. The experimentally reported solar cell parameters can be found using the proposed model described here.

High-throughput characterization of stresses in thin film materials libraries using Si cantilever array wafers and digital holographic microscopy

International Nuclear Information System (INIS)

Lai, Y. W.; Ludwig, A.; Hamann, S.; Ehmann, M.

2011-01-01

We report the development of an advanced high-throughput stress characterization method for thin film materials libraries sputter-deposited on micro-machined cantilever arrays consisting of around 1500 cantilevers on 4-inch silicon-on-insulator wafers. A low-cost custom-designed digital holographic microscope (DHM) is employed to simultaneously monitor the thin film thickness, the surface topography and the curvature of each of the cantilevers before and after deposition. The variation in stress state across the thin film materials library is then calculated by Stoney's equation based on the obtained radii of curvature of the cantilevers and film thicknesses. DHM with nanometer-scale out-of-plane resolution allows stress measurements in a wide range, at least from several MPa to several GPa. By using an automatic x-y translation stage, the local stresses within a 4-inch materials library are mapped with high accuracy within 10 min. The speed of measurement is greatly improved compared with the prior laser scanning approach that needs more than an hour of measuring time. A high-throughput stress measurement of an as-deposited Fe-Pd-W materials library was evaluated for demonstration. The fast characterization method is expected to accelerate the development of (functional) thin films, e.g., (magnetic) shape memory materials, whose functionality is greatly stress dependent.

Surface and interface characterization of thin-film silicon solar cell structures

Energy Technology Data Exchange (ETDEWEB)

Gerlach, Dominic

2013-02-21

The properties of Si thin films for solar cells, the interaction with different substrates and the influence of dopants are examined with synchrotron based x-ray spectroscopy - primarily X-ray emission spectroscopy (XES) and hard X-ray photoelectron spectroscopy (HAXPES). The films are studied as-deposited (i.e., amorphous, a-Si) and after conversion into polycrystalline (poly-Si) employing solid phase crystallization (SPC). Si L{sub 2,3} XES spectra of thin-film Si samples can be described by a superposition of a-Si and monocrystalline Si-wafer (c-Si) reference spectra. According to a quantification based on that superposition principle, none of the investigated samples are completely crystallized - a measurable a-Si component always remains (5-20 %) regardless of deposition and treatment conditions. Based on additional results from electron back scattering diffraction different models are developed which may explain this finding. According to these models, the remnant a-Si component can be attributed to amorphous/disordered material at the grain boundaries. Using one of these models, the thickness of this grain-surrounding material s could be approximated to be (1.5 {+-} 0.5) nm. Further investigations of the SPC process reveal a faster crystallization for boron-doped samples, and a slower crystallization for phosphorous-doped samples, when compared to the crystallization of undoped a Si:H thin films. The peculiarities of B K XES spectra (and observed changes upon SPC) indicate that boron could act as a nucleation center promoting crystallization. Si L{sub 2,3} XES spectra of a-Si:H and P-doped poly-Si exhibit spectral features above the valence band maximum at 100 eV that could be attributed to a-Si defect states and n{sup +}-dopant states, respectively. The SPC crystallization velocity of Si thin films on ZnO:Al/glass is found to be faster than that on SiNx/glass substrate. Multiple indications for oxidization at the poly-Si/ZnO:Al interface are found based on

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.

Cu2SixSn1-xS3 Thin Films Prepared by Reactive Magnetron Sputtering For Low-Cost Thin Film Solar Cells

Science.gov (United States)

Yan, Chang; Liu, Fang-Yang; Lai, Yan-Qing; Li, Jie; Liu, Ye-Xiang

2011-10-01

We report the preparation of Cu2SixSn1-xS3 thin films for thin film solar cell absorbers using the reactive magnetron co-sputtering technique. Energy dispersive spectrometer and x-ray diffraction analyses indicate that Cu2Si1-xSnxS3 thin films can be synthesized successfully by partly substituting Si atoms for Sn atoms in the Cu2SnS3 lattice, leading to a shrinkage of the lattice, and, accordingly, by 2θ shifting to larger values. The blue shift of the Raman peak further confirms the formation of Cu2SixSn1-xS3. Environmental scanning electron microscope analyses reveal a polycrystalline and homogeneous morphology with a grain size of about 200-300 nm. Optical measurements indicate an optical absorption coefficient of higher than 104 cm-1 and an optical bandgap of 1.17±0.01 eV.

Design principle for absorption enhancement with nanoparticles in thin-film silicon solar cells

International Nuclear Information System (INIS)

Xu, Yuanpei; Xuan, Yimin

2015-01-01

The use of nanoparticles in solar cells has created many controversies. In this paper, different mechanisms of nanoparticles with different materials with diameters varying from 50 to 200 nm, surface coverage at 5, 20, and 60 %, and different locations are analyzed systematically for efficient light trapping in a thin-film c-Si solar cell. Mie theory and the finite difference time domain method are used for analysis to give a design principle with nanoparticles for the solar cell application. Metals exhibit plasmonic resonances and angular scattering, while dielectrics show anti-reflection and scattering in the incident direction. A table is given to summarize the advantages and disadvantages in different conditions. The silicon absorption enhancement with nanoparticles on top is mainly in the shorter wavelengths below 700 nm, and both Al and SiO 2 nanoparticles with diameter around 100 nm show the most significant enhancement. The silicon absorption enhancement with embedded nanoparticles takes place in the longer wavelengths over 700 nm, and Ag and SiO 2 nanoparticles with larger diameter around 200 nm perform better. However, the light absorbed by Ag nanoparticles will be converted to heat and will lead to decrease in cell efficiency; hence, the choice of metallic nanoparticles in applications to solar cells should be carefully considered. The design principle proposed in this work gives a guideline by choosing reasonable parameters for the different requirements in the application of thin-film solar cells

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

Thin-Film Materials Synthesis and Processing Facility

Data.gov (United States)

Federal Laboratory Consortium — FUNCTION: Provides a wide capability for deposition and processing of thin films, including sputter and ion-beam deposition, thermal evaporation, electro-deposition,...

Liquid crystals for organic thin-film transistors

Science.gov (United States)

Iino, Hiroaki; Usui, Takayuki; Hanna, Jun-Ichi

2015-04-01

Crystalline thin films of organic semiconductors are a good candidate for field effect transistor (FET) materials in printed electronics. However, there are currently two main problems, which are associated with inhomogeneity and poor thermal durability of these films. Here we report that liquid crystalline materials exhibiting a highly ordered liquid crystal phase of smectic E (SmE) can solve both these problems. We design a SmE liquid crystalline material, 2-decyl-7-phenyl-[1]benzothieno[3,2-b][1]benzothiophene (Ph-BTBT-10), for FETs and synthesize it. This material provides uniform and molecularly flat polycrystalline thin films reproducibly when SmE precursor thin films are crystallized, and also exhibits high durability of films up to 200 °C. In addition, the mobility of FETs is dramatically enhanced by about one order of magnitude (over 10 cm2 V-1 s-1) after thermal annealing at 120 °C in bottom-gate-bottom-contact FETs. We anticipate the use of SmE liquid crystals in solution-processed FETs may help overcome upcoming difficulties with novel technologies for printed electronics.

Ion beam analysis of Cu(In,Ga)Se{sub 2} thin film solar cells

Energy Technology Data Exchange (ETDEWEB)

Karydas, A.G. [International Atomic Energy Agency (IAEA), IAEA Laboratories, Nuclear Science and Instrumentation Laboratory, A-2444 Seibersdorf (Austria); Institute of Nuclear and Particle Physics, NCSR “Demokritos”, 153 10 Aghia Paraskevi, Athens Greece (Greece); Streeck, C. [Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin (Germany); Radovic, I. Bogdanovic [Ruđer Bošković Institute (RBI), Zagreb (Croatia); Kaufmann, C.; Rissom, T. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Beckhoff, B. [Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin (Germany); Jaksic, M. [Ruđer Bošković Institute (RBI), Zagreb (Croatia); Barradas, N.P. [Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, E. N. 10, Apartado 21, 2686-953 Sacavém (Portugal)

2015-11-30

Graphical abstract: - Highlights: • Elemental depth profiles for various CIGS thin films were quantitatively determined. • Pure absorbers, complete cell and bilayer solar cells were prepared and analyzed. • Synergistic PIXE and RBS analysis of thin solar cells using alpha beam particles. • High energy alpha beam resolved completely the Indium depth profile. • Synchrotron based Reference Free GIXRF quantitative analysis validated IBA results. - Abstract: The present work investigates the potential of ion beam analysis (IBA) techniques such as the Rutherford backscattering spectrometry (RBS) and particle induced X-ray emission (PIXE) using helium ions to provide quantitative in-depth elemental analysis of various types of Cu(In,Ga)Se{sub 2} thin films. These films with a thickness of about 2 μm are used as absorber layers in photovoltaic devices with continuously increasing the performance of this technology. The preparation process generally aims to obtain an in-depth gradient of In and Ga concentrations that optimizes the optoelectronic and electrical properties of the solar cell. The measurements were performed at directly accessible single or double layered CIGS absorbers and at buried absorbers in completed thin film solar cells. The IBA data were analyzed simultaneously in order to derive best fitted profiles that match all experimental RBS and PIXE spectra. For some samples elemental profiles deduced form synchrotron based, reference free grazing incidence X-ray fluorescence analysis were compared with the IBA results and an overall good agreement was observed within quoted uncertainties.

A comparison of light-coupling into high and low index nanostructured photovoltaic thin films

Directory of Open Access Journals (Sweden)

T. Pfadler

2015-06-01

Full Text Available Periodically structured electrodes are typically introduced to thin-film photovoltaics for the purpose of light management. Highly effective light-trapping and optimal in-coupling of light is crucial to enhance the overall device performance in such thin-film systems. Here, wavelength-scale structures are transferred via direct laser interference patterning to electron-selective TiO2 electrodes. Two representative thin-film solar cell architectures are deposited on top: an organic solar cell featuring blended P3HT:PCBM as active material, and a hybrid solar cell with Sb2S3 as inorganic active material. A direct correlation in the asymmetry in total absorption enhancement and in structure-induced light in-coupling is spectroscopically observed for the two systems. The structuring is shown to be beneficial for the total absorption enhancement if a high n active material is deposited on TiO2, but detrimental for a low n material. The refractive indices of the employed materials are determined via spectroscopic ellipsometry. The study outlines that the macroscopic Fresnel equations can be used to investigate the spectroscopically observed asymmetry in light in-coupling at the nanostructured TiO2 active material interfaces by visualizing the difference in reflectivity caused by the asymmetry in refractive indices.

Fabrication of high quality Cu2SnS3 thin film solar cell with 1.12% power conversion efficiency obtain by low cost environment friendly sol-gel technique

Science.gov (United States)

Chaudhari, J. J.; Joshi, U. S.

2018-03-01

Cu2SnS3 (CTS) is an emerging ternery chalcogenide material with great potential application in thin film solar cells. We present here high quality Cu2SnS3 thin films using a facile spin coating method. The as deposited films of CTS were sulphurized in a graphite box using tubular furnace at 520 °C for 60 min at the rate of 2.83 °C min-1 in argon atmosphere. X-ray diffraction (XRD) and Raman spectroscopy studies confirm tetragonal phase and absence of any secondary phase in sulphurized CTS thin films. X-ray photoelectron spectroscopy (XPS) demonstrates that Cu and Sn are in +1 and +4 oxidation state respectively. Surface morphology of CTS films were analyzed by field emission scanning electron microscope and atomic force microscope (AFM), which revealed a smooth surface with roughness (RMS) of 6.32 nm for sulphurized CTS film. Hall measurements confirmed p-type conductivity with hole concentartion of sulphurized CTS thin film is of 6.5348 × 1020 cm-3. UV-vis spectra revealed a direct energy band gap varies from 1.45 eV to 1.01 eV for as-deposited and sulphurized CTS thin film respectively. Such band gap values are optimum for semiconductor material as an absorber layer of thin film solar cell. The CTS thin film solar cell had following structure: SLG/FTO/ZnO/CTS/Al with short circuit current density of (Jsc) of 11.6 mA cm-2, open circuit voltage (Voc) of 0.276 V, active area of 0.16 cm2, fill factor (FF) of 35% and power conversion efficiency of 1.12% under AM 1.5 (100 mW cm-2) illumination in simulated standard test conditions.

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

Directory of Open Access Journals (Sweden)

Gurpreet Kaur

2015-02-01

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

Nanostructured manganese oxide thin films as electrode material for supercapacitors

Science.gov (United States)

Xia, Hui; Lai, Man On; Lu, Li

2011-01-01

Electrochemical capacitors, also called supercapacitors, are alternative energy storage devices, particularly for applications requiring high power densities. Recently, manganese oxides have been extensively evaluated as electrode materials for supercapacitors due to their low cost, environmental benignity, and promising supercapacitive performance. In order to maximize the utilization of manganese oxides as the electrode material for the supercapacitors and improve their supercapacitive performance, the nanostructured manganese oxides have therefore been developed. This paper reviews the synthesis of the nanostructured manganese oxide thin films by different methods and the supercapacitive performance of different nanostructures.

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

Transparent electrode requirements for thin film solar cell modules

KAUST Repository

Rowell, Michael W.; McGehee, Michael D.

2011-01-01

The transparent conductor (TC) layer in thin film solar cell modules has a significant impact on the power conversion efficiency. Reflection, absorption, resistive losses and lost active area either from the scribed interconnect region in monolithically integrated modules or from the shadow losses of a metal grid in standard modules typically reduce the efficiency by 10-25%. Here, we perform calculations to show that a competitive TC must have a transparency of at least 90% at a sheet resistance of less than 10 Ω/sq (conductivity/absorptivity ≥ 1 Ω -1) for monolithically integrated modules. For standard modules, losses are much lower and the performance of alternative lower cost TC materials may already be sufficient to replace conducting oxides in this geometry. © 2011 The Royal Society of Chemistry.

Thin films of single-walled carbon nanotubes promote human osteoblastic cells (Saos-2) proliferation in low serum concentrations

International Nuclear Information System (INIS)

Akasaka, Tsukasa; Yokoyama, Atsuro; Matsuoka, Makoto; Hashimoto, Takeshi; Watari, Fumio

2010-01-01

One strategy used for the regeneration of bone is the development of cell culture substrates and scaffolds that can control osteoblast proliferation and differentiation. In recent investigations, carbon nanotubes (CNTs) have been utilized as scaffolds for osteoblastic cell cultures; however, there are only a few reports describing the proliferation of osteoblastic cells on thin CNT films; in particular, the effects of serum concentration on cell proliferation have not been studied. In the present study, we prepared culture dishes with homogeneous thin or thick films of non-modified CNTs and examined the effect of serum concentrations on human osteoblastic cells (Saos-2) proliferation in these culture dishes. We demonstrated that the ratio of cell proliferation was strongly affected by the concentration of serum. Interestingly, single-walled carbon nanotube (SWNT) thin films were found to be the most effective substrate for the proliferation of Saos-2 cells in low concentrations of serum. Thus, thin SWNT films may be used as an effective biomaterial for the culture of Saos-2 cells in low serum concentrations.

Photon confinement in high-efficiency, thin-film III-V solar cells obtained by epitaxial lift-off

International Nuclear Information System (INIS)

Schermer, J.J.; Bauhuis, G.J.; Mulder, P.; Haverkamp, E.J.; Deelen, J. van; Niftrik, A.T.J. van; Larsen, P.K.

2006-01-01

Using the epitaxial lift-off (ELO) technique, a III-V device structure can be separated from its GaAs substrate by selective wet etching of a thin release layer. The thin-film structures obtained by the ELO process can be cemented or van der Waals bonded on arbitrary smooth surface carriers for further processing. It is shown that the ELO method, initially able to separate millimetre-sized GaAs layers with a lateral etch rate of about 1 mm/h, has been developed to a process capable to free the entire 2-in. epitaxial structures from their substrates with etch rates up to 30 mm/h. With these characteristics the method has a large potential for the production of high efficiency thin-film solar cells. By choosing the right deposition and ELO strategy, the thin-film III-V cells can be adequately processed on both sides allowing for an entire range of new cell structures. In the present work, the performance of semi-transparent bifacial solar cells, produced by the deposition of metal grid contacts on both sides, was evaluated. Reflection of light at the rear side of the bifacial GaAs solar cells was found to result in an enhanced collection probability of the photon-induced carriers compared to that of regular III-V cells on a GaAs substrate. To enhance this effect, thin-film GaAs cells with gold mirror back contacts were prepared. Even in their present premature stage of development, these single-junction thin-film cells reached a record efficiency of 24.5% which is already very close to the 24.9% efficiency that was obtained with a regular GaAs cell on a GaAs substrate. From this it could be concluded that, as a result of the photon confinement, ELO cells require a significantly thinner base layer than regular GaAs cells while at the same time they have the potential to reach a higher efficiency

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.

Photon management in thin-film solar cells; Photon-Management in Duennschicht-Solarzellen

Energy Technology Data Exchange (ETDEWEB)

Fahr, Stephan

2011-11-22

In this thesis procedures were presented, which modify the propagation of the incident light in such a way that by this the efficiency of thin-film solar cells is increased. The strength of the presented numerical studies lies thereby in the rigorous solution of Maxwell's equations. Fundamental statements concerning the lay-out of an ideal texture could be made, which for present thin-film solar cells over the whole relevant spectral range both suppresses reflection losses and leads to an elongation of the effective path. Object of the thesis was also the design of a spectral- and angular-selective filter, which confines the acceptance angle of a solar cell with the aim of an improved absorption in the long-wave spectral region. Furthermore also tandem cells on the base of amorphous and microcrystalline silicon were studied.

Thin-film filament-based solar cells and modules

Science.gov (United States)

Tuttle, J. R.; Cole, E. D.; Berens, T. A.; Alleman, J.; Keane, J.

1997-04-01

This concept paper describes a patented, novel photovoltaic (PV) technology that is capable of achieving near-term commercialization and profitability based upon design features that maximize product performance while minimizing initial and future manufacturing costs. DayStar Technologies plans to exploit these features and introduce a product to the market based upon these differential positions. The technology combines the demonstrated performance and reliability of existing thin-film PV product with a cell and module geometry that cuts material usage by a factor of 5, and enhances performance and manufacturability relative to standard flat-plate designs. The target product introduction price is 1.50/Watt-peak (Wp). This is approximately one-half the cost of the presently available PV product. Additional features include: increased efficiency through low-level concentration, no scribe or grid loss, simple series interconnect, high voltage, light weight, high-throughput manufacturing, large area immediate demonstration, flexibility, modularity.

Management of light absorption in extraordinary optical transmission based ultra-thin-film tandem solar cells

International Nuclear Information System (INIS)

Mashooq, Kishwar; Talukder, Muhammad Anisuzzaman

2016-01-01

Although ultra-thin-film solar cells can be attractive in reducing the cost, they suffer from low absorption as the thickness of the active layer is usually much smaller than the wavelength of incident light. Different nano-photonic techniques, including plasmonic structures, are being explored to increase the light absorption in ultra-thin-film solar cells. More than one layer of active materials with different energy bandgaps can be used in tandem to increase the light absorption as well. However, due to different amount of light absorption in different active layers, photo-generated currents in different active layers will not be the same. The current mismatch between the tandem layers makes them ineffective in increasing the efficiency. In this work, we investigate the light absorption properties of tandem solar cells with two ultra-thin active layers working as two subcells and a metal layer with periodically perforated holes in-between the two subcells. While the metal layer helps to overcome the current mismatch, the periodic holes increase the absorption of incident light by helping extraordinary optical transmission of the incident light from the top to the bottom subcell, and by coupling the incident light to plasmonic and photonic modes within ultra-thin active layers. We extensively study the effects of the geometry of holes in the intermediate metal layer on the light absorption properties of tandem solar cells with ultra-thin active layers. We also study how different metals in the intermediate layer affect the light absorption; how the geometry of holes in the intermediate layer affects the absorption when the active layer materials are changed; and how the intermediate metal layer affects the collection of photo-generated electron-hole pairs at the terminals. We find that in a solar cell with 6,6-phenyl C61-butyric acid methyl ester top subcell and copper indium gallium selenide bottom subcell, if the periodic holes in the metal layer are square or

Management of light absorption in extraordinary optical transmission based ultra-thin-film tandem solar cells

Energy Technology Data Exchange (ETDEWEB)

Mashooq, Kishwar; Talukder, Muhammad Anisuzzaman, E-mail: anis@eee.buet.ac.bd [Department of Electrical and Electronic Engineering, Bangladesh University of Engineering and Technology, Dhaka 1205 (Bangladesh)

2016-05-21

Although ultra-thin-film solar cells can be attractive in reducing the cost, they suffer from low absorption as the thickness of the active layer is usually much smaller than the wavelength of incident light. Different nano-photonic techniques, including plasmonic structures, are being explored to increase the light absorption in ultra-thin-film solar cells. More than one layer of active materials with different energy bandgaps can be used in tandem to increase the light absorption as well. However, due to different amount of light absorption in different active layers, photo-generated currents in different active layers will not be the same. The current mismatch between the tandem layers makes them ineffective in increasing the efficiency. In this work, we investigate the light absorption properties of tandem solar cells with two ultra-thin active layers working as two subcells and a metal layer with periodically perforated holes in-between the two subcells. While the metal layer helps to overcome the current mismatch, the periodic holes increase the absorption of incident light by helping extraordinary optical transmission of the incident light from the top to the bottom subcell, and by coupling the incident light to plasmonic and photonic modes within ultra-thin active layers. We extensively study the effects of the geometry of holes in the intermediate metal layer on the light absorption properties of tandem solar cells with ultra-thin active layers. We also study how different metals in the intermediate layer affect the light absorption; how the geometry of holes in the intermediate layer affects the absorption when the active layer materials are changed; and how the intermediate metal layer affects the collection of photo-generated electron-hole pairs at the terminals. We find that in a solar cell with 6,6-phenyl C61-butyric acid methyl ester top subcell and copper indium gallium selenide bottom subcell, if the periodic holes in the metal layer are square or

The origin of local strain in highly epitaxial oxide thin films.

Science.gov (United States)

Ma, Chunrui; Liu, Ming; Chen, Chonglin; Lin, Yuan; Li, Yanrong; Horwitz, J S; Jiang, Jiechao; Meletis, E I; Zhang, Qingyu

2013-10-31

The ability to control the microstructures and physical properties of hetero-epitaxial functional oxide thin films and artificial structures is a long-sought goal in functional materials research. Normally, only the lattice misfit between the film and the substrate is considered to govern the physical properties of the epitaxial films. In fact, the mismatch of film unit cell arrangement and the Surface-Step-Terrace (SST) dimension of the substrate, named as "SST residual matching", is another key factor that significantly influence the properties of the epitaxial film. The nature of strong local strain induced from both lattice mismatch and the SST residual matching on ferroelectric (Ba,Sr)TiO3 and ferromagnetic (La,Ca)MnO3 thin films are systematically investigated and it is demonstrated that this combined effect has a dramatic impact on the physical properties of highly epitaxial oxide thin films. A giant anomalous magnetoresistance effect (~10(10)) was achieved from the as-designed vicinal surfaces.

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.

Superior light trapping in thin film silicon solar cells through nano imprint lithography

Energy Technology Data Exchange (ETDEWEB)

Soppe, W.J.; Dorenkamper, M.S.; Schropp, R.E.I.; Pex, P.P.A.C.

2013-10-15

ECN and partners have developed a fabrication process based on nanoimprint lithography (NIL) of textures for light trapping in thin film solar cells such as thin-film silicon, OPV, CIGS and CdTe. The process can be applied in roll-to-roll mode when using a foil substrate or in roll-to-plate mode when using a glass substrate. The lacquer also serves as an electrically insulating layer for cells if steel foil is used as substrate, to enable monolithic series interconnection. In this paper we will show the superior light trapping in thin film silicon solar cells made on steel foil with nanotextured back contacts. We have made single junction a-Si and {mu}c-Si and a-Si/{mu}c-Si tandem cells, where we applied several types of nano-imprints with random and periodic structures. We will show that the nano-imprinted back contact enables more than 30% increase of current in comparison with non-textured back contacts and that optimized periodic textures outperform state-of-the-art random textures. For a-Si cells we obtained Jsc of 18 mA/cm{sup 2} and for {mu}c-Si cells more than 24 mA/cm{sup 2}. Tandem cells with a total Si absorber layer thickness of only 1350 nm have an initial efficiency of 11%.

CIGS thin film solar cell prepared by reactive co-sputtering

Science.gov (United States)

Kim, Jeha; Lee, Ho-Sub; Park, Nae-Man

2013-09-01

The reactive co-sputtering was developed as a new way of preparing high quality CuInGaSe2(CIGS) films from two sets of targets; Cu0.6Ga 0.4 and Cu0.4In0.6 alloy and Cu and (In0.7Ga0.3)2Se3 compound targets. During sputtering, Cu, In, Ga metallic elements as well as the compound materials were reacted to form CIGS simultaneously in highly reactive elemental Se atmosphere generated by a thermal cracker. CIGS layer had been grown on Mo/soda-lime glass(SLG) at 500°C. For both sets of targets, we controlled the composition of CIGS thin film by changing the RF power for target components. All the films showed a preferential (112) orientation as observed from X-ray diffraction analysis. The composition ratios of CIGS were easily set to 0.71-0.95, 0.10-0.30 for [Cu]/[III] and [Ga]/[III], respectively. The grain size and the surface roughness of a CIGS film increased as the [Cu]/[III] ratios increased. The solar cells were fabricated using a standard base line process in the device structure of grid/ITO/i-ZnO/CdS/CIGS/Mo/ SLG. The best performance was obtained the performance of Voc = 0.45 V, Jsc =35.6, FF = 0.535, η = 8.6% with a 0.9 μm-CIGS solar cell from alloy targets while Voc = 0.54 V, Jsc =30.8, FF = 0.509, η = 8.5% with a 0.8 μm-CIGS solar cell from Cu and (In0.7Ga0.3)2Se3.

Effect of sodium addition on Cu-deficient CuIn{sub 1-x}Ga{sub x}S{sub 2} thin film solar cells

Energy Technology Data Exchange (ETDEWEB)

Vasekar, Parag S.; Dhere, Neelkanth G. [Florida Solar Energy Center, University of Central Florida, 1679 Clearlake Road, Cocoa, FL 32922 (United States)

2009-01-15

Chalcopyrites are important contenders among solar-cell materials due to direct band gap and very high-absorption coefficients. Copper-indium-gallium disulfide (CIGS2) is a chalcopyrite material with a near-optimum band gap of 1.5 eV for terrestrial as well as space applications. At FSEC PV Materials Laboratory, record efficiency of 11.99% has been achieved on a 2.7 {mu}m CIGS2 thin film prepared by sulfurization. There are reports of influence of sodium on copper-indium-gallium selenide (CIGS) as well as copper-indium disulfide (CIS2) solar cells. However, this is the first of its kind approach to study the effect of sodium on CIGS2 solar cells and resulting in encouraging efficiencies. Copper-deficient CIGS2 thin films were prepared with and without the addition of sodium fluoride (NaF). Effects of addition of NaF on the microstructure and device electrical properties are presented in this work. (author)

Wet-Chemical Surface Texturing of Sputter-Deposited ZnO:Al Films as Front Electrode for Thin-Film Silicon Solar Cells

Directory of Open Access Journals (Sweden)

Xia Yan

2015-01-01

Full Text Available Transparent conductive oxides (TCOs play a major role as the front electrodes of thin-film silicon (Si solar cells, as they can provide optical scattering and hence improved photon absorption inside the devices. In this paper we report on the surface texturing of aluminium-doped zinc oxide (ZnO:Al or AZO films for improved light trapping in thin-film Si solar cells. The AZO films are deposited onto soda-lime glass sheets via pulsed DC magnetron sputtering. Several promising AZO texturing methods are investigated using diluted hydrochloric (HCl and hydrofluoric acid (HF, through a two-step etching process. The developed texturing procedure combines the advantages of the HCl-induced craters and the smaller and jagged—but laterally more uniform—features created by HF etching. In the two-step process, the second etching step further enhances the optical haze, while simultaneously improving the uniformity of the texture features created by the HCl etch. The resulting AZO films show large haze values of above 40%, good scattering into large angles, and a surface angle distribution that is centred at around 30°, which is known from the literature to provide efficient light trapping for thin-film Si solar cells.

High-temperature fabrication of Ag(In,Ga)Se{sub 2} thin films for applications in solar cells

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xianfeng [International Center for Science and Engineering Programs, Waseda University, Tokyo (Japan); Yamada, Akira [Department of Physical Electronics, Tokyo Institute of Technology, Tokyo (Japan); Kobayashi, Masakazu [Department of Electrical Engineering and Bioscience, Waseda University, Tokyo (Japan); Kagami Memorial Research Institute for Materials Science, Waseda University, Tokyo (Japan)

2017-10-15

Molecular beam epitaxy was used to fabricate Ag(In,Ga)Se{sub 2} (AIGS) thin films. To improve the diffusion of Ag, high-temperature deposition and high-temperature annealing methods were applied to fabricate AIGS films. The as-grown AIGS thin films were then used to make AIGS solar cells. We found that grain size and crystallinity of AIGS films were considerably improved by increasing the deposition and annealing temperature. For high-temperature deposition, temperatures over 600 C led to decomposition of the AIGS film, desorption of In, and deterioration of its crystallinity. The most appropriate deposition temperature was 590 C and a solar cell with a power conversion efficiency of 4.1% was obtained. High-temperature annealing of the AIGS thin films showed improved crystallinity as annealing temperature was increased and film decomposition and In desorption were prevented. A solar cell based on this film showed the highest conversion efficiency of 6.4% when annealed at 600 C. When the annealing temperature was further increased to 610 C, the performance of the cell deteriorated due to loss of the out-of-plane Ga gradient. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

A computational study on the energy bandgap engineering in performance enhancement of CdTe thin film solar cells

Directory of Open Access Journals (Sweden)

Ameen M. Ali

Full Text Available In this study, photovoltaic properties of CdTe thin film in the configuration of n-SnO2/n-CdS/p-CdTe/p-CdTe:Te/metal have been studied by numerical simulation software named “Analysis of Microelectronic and Photonic Structure” (AMPS-1D. A modified structure for CdTe thin film solar cell has been proposed by numerical analysis with the insertion of a back contact buffer layer (CdTe:Te. This layer can serve as a barrier that will decelerate the copper diffusion in CdTe solar cell. Four estimated energy bandgap relations versus the Tellurium (Te concentrations and the (CdTe:Te layer thickness have been examined thoroughly during simulation. Correlation between energy bandgap with the CdTe thin film solar cell performance has also been established. Keywords: Numerical modelling, CdTe thin film, Solar cell, AMPS-1D, Bandgap

High-throughput characterization of stresses in thin film materials libraries using Si cantilever array wafers and digital holographic microscopy.

Science.gov (United States)

Lai, Y W; Hamann, S; Ehmann, M; Ludwig, A

2011-06-01

We report the development of an advanced high-throughput stress characterization method for thin film materials libraries sputter-deposited on micro-machined cantilever arrays consisting of around 1500 cantilevers on 4-inch silicon-on-insulator wafers. A low-cost custom-designed digital holographic microscope (DHM) is employed to simultaneously monitor the thin film thickness, the surface topography and the curvature of each of the cantilevers before and after deposition. The variation in stress state across the thin film materials library is then calculated by Stoney's equation based on the obtained radii of curvature of the cantilevers and film thicknesses. DHM with nanometer-scale out-of-plane resolution allows stress measurements in a wide range, at least from several MPa to several GPa. By using an automatic x-y translation stage, the local stresses within a 4-inch materials library are mapped with high accuracy within 10 min. The speed of measurement is greatly improved compared with the prior laser scanning approach that needs more than an hour of measuring time. A high-throughput stress measurement of an as-deposited Fe-Pd-W materials library was evaluated for demonstration. The fast characterization method is expected to accelerate the development of (functional) thin films, e.g., (magnetic) shape memory materials, whose functionality is greatly stress dependent. © 2011 American Institute of Physics

ANNEALING OF POLYCRYSTALLINE THIN FILM SILICON SOLAR CELLS IN WATER VAPOUR AT SUB-ATMOSPHERIC PRESSURES

Directory of Open Access Journals (Sweden)

Peter Pikna

2014-10-01

Full Text Available Thin film polycrystalline silicon (poly-Si solar cells were annealed in water vapour at pressures below atmospheric pressure. PN junction of the sample was contacted by measuring probes directly in the pressure chamber filled with steam during passivation. Suns-VOC method and a Lock-in detector were used to monitor an effect of water vapour to VOC of the solar cell during whole passivation process (in-situ. Tested temperature of the sample (55°C – 110°C was constant during the procedure. Open-circuit voltage of a solar cell at these temperatures is lower than at room temperature. Nevertheless, voltage response of the solar cell to the light flash used during Suns-VOC measurements was good observable. Temperature dependences for multicrystalline wafer-based and polycrystalline thin film solar cells were measured and compared. While no significant improvement of thin film poly-Si solar cell parameters by annealing in water vapour at under-atmospheric pressures was observed up to now, in-situ observation proved required sensitivity to changing VOC at elevated temperatures during the process.

Fiscal 1998 New Sunshine Program achievement report. Development for practical application of photovoltaic system - Development of thin-film solar cell manufacturing technology (Development of low-cost large-area module manufacturing technology - Development of next-generation thin-film solar cell manufacturing technology - Development of thin-film polycrystalline solar cell module manufacturing technology); 1998 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu / tei cost daimenseki module seizo gijutsu kaihatsu / jisedai usumaku taiyo denchi no seizo gijutsu kaihatsu (usumaku takessho taiyo denchi module no seizo gijutsu kaihatsu)

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

The aim is to realize the practical application of the above-named solar module expected to exhibit higher efficiency and reliability and achieve cost reduction through consumption of less materials. In fiscal 1998, 1) technologies were developed to reduce substrate warpage during recrystallization for the higher-throughput fabrication of high-quality thin films and 2) technologies were also developed for the realization of higher-throughput fabrication of thin films and for efficiency improvement for thin-film modules. Under item 1), experiments were conducted by simulation for reducing warpage to occur in thin-film polycrystalline Si substrates during fabrication by melting and recrystallization. Under item 2), for the development of thin-film cell high-throughput technologies, studies were started on a more practical hydrogen plasma process to challenge the conventional process of crystal defect inactivation by hydrogen ion injection with which achievement of high throughputs is difficult. For the development of technologies for the enhancement of thin-film module efficiency, efforts were exerted to realize a 10cm times 10cm square shape for the enhancement of efficiency in the process of filling modules with cells. These efforts achieved a great step toward future practical application. (NEDO)

Enhanced photocurrent in thin-film amorphous silicon solar cells via shape controlled three-dimensional nanostructures

International Nuclear Information System (INIS)

Hilali, Mohamed M; Banerjee, Sanjay; Sreenivasan, S V; Yang Shuqiang; Miller, Mike; Xu, Frank

2012-01-01

In this paper, we have explored manufacturable approaches to sub-wavelength controlled three-dimensional (3D) nano-patterns with the goal of significantly enhancing the photocurrent in amorphous silicon solar cells. Here we demonstrate efficiency enhancement of about 50% over typical flat a-Si thin-film solar cells, and report an enhancement of 20% in optical absorption over Asahi textured glass by fabricating sub-wavelength nano-patterned a-Si on glass substrates. External quantum efficiency showed superior results for the 3D nano-patterned thin-film solar cells due to enhancement of broadband optical absorption. The results further indicate that this enhanced light trapping is achieved with minimal parasitic absorption losses in the deposited transparent conductive oxide for the nano-patterned substrate thin-film amorphous silicon solar cell configuration. Optical simulations are in good agreement with experimental results, and also show a significant enhancement in optical absorption, quantum efficiency and photocurrent. (paper)

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

Gas phase considerations for the deposition of thin film silicon solar cells by VHF-PECVD at low substrate temperatures

NARCIS (Netherlands)

Rath, J.K.; Verkerk, A.D.; Brinza, M.; Schropp, R.E.I.; Goedheer, W.J.; Krzhizhanovskaya, V.V.; Gorbachev, Y.E.; Orlov, K.E.; Khilkevitch, E.M.; Smirnov, A.S.

2008-01-01

Fabrication of thin film silicon solar cells on cheap plastics or paper-like substrate requires deposition process at very low substrate temperature, typically ≤ 100 °C. In a chemical vapor deposition process, low growth temperatures lead to materials with low density, high porosity, high disorder

Research Progress on Measurement Methods and Influence Factors of Thin-film Stress

Directory of Open Access Journals (Sweden)

MA Yibo

2018-02-01

Full Text Available With the size of thin-film electronic devices decreasing, the film stress became an important reason for the failure of thin film devices. Film stress not only affected the membrane structure, but also associated with film optics, electricity, mechanics and other properties, therefore film stress turned into one hot spot in the research field of thin-film materials. This paper reviewed the latest research progress of film stress, substrate curvature method, X-ray diffraction technique and Raman spectroscopy, several frequently used stress measuring techniques were compared and analyzed, and composition ratios of thin film, substrate types, magnetron sputtering process parameters (sputtering power, work pressure, substrate temperature and annealing etc. factors influencing thin film stress were summarized. It was found that substrate curvature method was suitable for measuring almost all kinds of thin film materials. X-ray diffraction and Raman spectroscopy were just fit for measuring materials with characteristic peaks. Nanoindentation method required extra stress-free samples as comparison experiments. During film fabrication and annealing process, film stress usually transited from compressive to tensile status, and several factors combined together could affect stress, so film stress could be reached the minimum value or even stress-free status through setting appropriate parameters. Finally, combined with film stress research status, accurate stress measurement methods for different materials as a thin-film stress research direction were introduced, and challenges in thin film detection range were pointed out.

Development of thin film cathodes for lithium-ion batteries in the material system Li–Mn–O by r.f. magnetron sputtering

International Nuclear Information System (INIS)

Fischer, J.; Adelhelm, C.; Bergfeldt, T.; Chang, K.; Ziebert, C.; Leiste, H.; Stüber, M.; Ulrich, S.; Music, D.; Hallstedt, B.; Seifert, H.J.

2013-01-01

Today most commercially available lithium ion batteries are still based on the toxic and expensive LiCoO 2 as a standard cathode material. However, lithium manganese based cathode materials are cheaper and environmentally friendlier. In this work cubic-LiMn 2 O 4 spinel, monoclinic-Li 2 MnO 3 and orthorhombic-LiMnO 2 thin films have been synthesized by non-reactive r.f. magnetron sputtering from two ceramic targets (LiMn 2 O 4 , LiMnO 2 ) in a pure argon discharge. The deposition parameters, namely target power and working gas pressure, were optimized in a combination with a post deposition heat treatment with respect to microstructure and electrochemical behavior. The chemical composition was determined using inductively coupled plasma optical emission spectroscopy and carrier gas hot extraction. The films' crystal structure, phase evolution and morphology were investigated by X-ray diffraction, micro Raman spectroscopy and scanning electron microscopy. Due to the fact that these thin films consist of the pure active material without any impurities, such as binders or conductive additives like carbon black, they are particularly well suited for measurements of the intrinsic physical properties, which is essential for fundamental understanding. The electrochemical behavior of the cubic and the orthorhombic films was investigated by galvanostatic cycling in half cells against metallic lithium. The cubic spinel films exhibit a maximum specific capacity of ∼ 82 mAh/g, while a specific capacity of nearly 150 mAh/g can be reached for the orthorhombic counterparts. These films are promising candidates for future all solid state battery applications. - Highlights: ► Synthesis of 3 Li–Mn–O structures by one up-scalable thin film deposition method ► Formation of o-LiMnO 2 by r.f. magnetron sputtering in combination with post-annealing ► Discharge capacity with o-LiMnO 2 cathodes twice as high as for c-LiMn 2 O 4 ► Thin film deposition of m-Li 2 MnO 3 and

Deposition and characterization of thin films of materials with application in cathodes for lithium rechargeable micro batteries

International Nuclear Information System (INIS)

Lopez I, J.

2007-01-01

In this thesis work is reported the deposition and characterization of thin films of materials of the type LiMO 2 , with M=Co and Ni, which have application in cathodes for micro-batteries of lithium ions. In the last years some investigators have reported that the electrochemical operation of the lithium ions batteries it can improve recovering the cathode, in bundle form, with some metal oxides as the Al 2 O 3 ; for that the study of the formation of thin films in bilayer form LiMO 2 /AI 2 O 3 is of interest in the development of lithium ions micro batteries. The thin films were deposited using the laser ablation technique studying the effect of some deposit parameters in the properties of the one formed material, as: laser fluence, substrate temperature and working atmosphere, with the purpose of optimizing it. In the case of the LiCoO 2 it was found that to use an inert atmosphere of argon allows to obtain the material with the correct composition. Additionally, with the use of a temperature in the substrate of 150 C is possible to obtain to the material with certain crystallinity grade that to the subjected being to a post-deposit thermal treatment at 300 C for three hours, it gives as result a totally crystalline material. In the case of the thin films of LiNiO 2 , it was necessary to synthesize the oxide starting from a reaction of solid state among nickel oxide (NiO) and lithium oxide (Li 2 O) obtaining stoichiometric LiNiO 2 . For the formation of the thin films of LiNiO 2 it was used an argon atmosphere and the laser fluence was varied, the deposits were carried out to two different substrates temperatures, atmosphere and 160 C. In both cases the material it was recovered with an alumina layer, found that this layer didn't modify the structural properties of the base oxide (LiCoO 2 and LiNiO 2 ). (Author)

Organic Thin Films Deposited by Emulsion-Based, Resonant Infrared, Matrix-Assisted Pulsed Laser Evaporation: Fundamentals and Applications

Science.gov (United States)

Ge, Wangyao

Thin film deposition techniques are indispensable to the development of modern technologies as thin film based optical coatings, optoelectronic devices, sensors, and biological implants are the building blocks of many complicated technologies, and their performance heavily depends on the applied deposition technique. Particularly, the emergence of novel solution-processed materials, such as soft organic molecules, inorganic compounds and colloidal nanoparticles, facilitates the development of flexible and printed electronics that are inexpensive, light weight, green and smart, and these thin film devices represent future trends for new technologies. One appealing feature of solution-processed materials is that they can be deposited into thin films using solution-processed deposition techniques that are straightforward, inexpensive, high throughput and advantageous to industrialize thin film based devices. However, solution-processed techniques rely on wet deposition, which has limitations in certain applications, such as multi-layered film deposition of similar materials and blended film deposition of dissimilar materials. These limitations cannot be addressed by traditional, vacuum-based deposition techniques because these dry approaches are often too energetic and can degrade soft materials, such as polymers, such that the performance of resulting thin film based devices is compromised. The work presented in this dissertation explores a novel thin film deposition technique, namely emulsion-based, resonant infrared, matrix-assisted pulsed laser evaporation (RIR-MAPLE), which combines characteristics of wet and dry deposition techniques for solution-processed materials. Previous studies have demonstrated the feasibility of emulsion-based RIR-MAPLE to deposit uniform and continuous organic, nanoparticle and blended films, as well as hetero-structures that otherwise are difficult to achieve. However, fundamental understanding of the growth mechanisms that govern

Strategies to prepare TiO2 thin films, doped with transition metal ions, that exhibit specific physicochemical properties to support osteoblast cell adhesion and proliferation

International Nuclear Information System (INIS)

Dhayal, Marshal; Kapoor, Renu; Sistla, Pavana Goury; Pandey, Ravi Ranjan; Kar, Satabisha; Saini, Krishan Kumar; Pande, Gopal

2014-01-01

Metal ion doped titanium oxide (TiO 2 ) thin films, as bioactive coatings on metal or other implantable materials, can be used as surfaces for studying the cell biological properties of osteogenic and other cell types. Bulk crystallite phase distribution and surface carbon–oxygen constitution of thin films, play an important role in determining the biological responses of cells that come in their contact. Here we present a strategy to control the polarity of atomic interactions between the dopant metal and TiO 2 molecules and obtain surfaces with smaller crystallite phases and optimal surface carbon–oxygen composition to support the maximum proliferation and adhesion of osteoblast cells. Our results suggest that surfaces, in which atomic interactions between the dopant metals and TiO 2 were less polar, could support better adhesion, spreading and proliferation of cells. - Highlights: • Electrochemical properties of dopants control the nature of TiO 2 thin films. • A model explains the correlation of dopant properties and behaviour of TiO 2 films. • Dopants with less polar interaction with TiO 2 exhibit better biological activity

Electrochemical Deposition of Lanthanum Telluride Thin Films and Nanowires

Science.gov (United States)

Chi, Su (Ike); Farias, Stephen; Cammarata, Robert

2013-03-01

Tellurium alloys are characterized by their high performance thermoelectric properties and recent research has shown nanostructured tellurium alloys display even greater performance than bulk equivalents. Increased thermoelectric efficiency of nanostructured materials have led to significant interests in developing thin film and nanowire structures. Here, we report on the first successful electrodeposition of lanthanum telluride thin films and nanowires. The electrodeposition of lanthanum telluride thin films is performed in ionic liquids at room temperature. The synthesis of nanowires involves electrodepositing lanthanum telluride arrays into anodic aluminum oxide (AAO) nanoporous membranes. These novel procedures can serve as an alternative means of simple, inexpensive and laboratory-environment friendly methods to synthesize nanostructured thermoelectric materials. The thermoelectric properties of thin films and nanowires will be presented to compare to current state-of-the-art thermoelectric materials. The morphologies and chemical compositions of the deposited films and nanowires are characterized using SEM and EDAX analysis.

Inverted organic solar cells with solvothermal synthesized vanadium-doped TiO2 thin films as efficient electron transport layer

Institute of Scientific and Technical Information of China (English)

Mehdi Ahmadi; Sajjad Rashidi Dafeh; Samaneh Ghazanfarpour; Mohammad Khanzadeh

2017-01-01

We investigated the effects of using different thicknesses of pure and vanadium-doped thin films of TiO2 as the electron transport layer in the inverted configuration of organic photovoltaic cells based on poly (3-hexylthiophene) P3HT:[6-6] phenyl-(6) butyric acid methyl ester (PCBM).1％ vanadium-doped TiO2 nanoparticles were synthesized via the solvothermal method.Crystalline structure,morphology,and optical properties of pure and vanadium-doped TiO2 thin films were studied by different techniques such as x-ray diffraction,scanning electron microscopy,transmittance electron microscopy,and UV-visible transmission spectrum.The doctor blade method which is compatible with roll-2-roll printing was used for deposition of pure and vanadium-doped TiO2 thin films with thicknesses of 30 nm and 60 nm.The final results revealed that the best thickness of TiO2 thin films for our fabricated cells was 30 nm.The cell with vanadium-doped TiO2 thin film showed slightly higher power conversion efficiency and great Jsc of 10.7 mA/cm2 compared with its pure counterpart.In the cells using 60 nm pure and vanadium-doped TiO2 layers,the cell using the doped layer showed much higher efficiency.It is remarkable that the extemal quantum efficiency of vanadium-doped TiO2 thin film was better in all wavelengths.

Nanocrystalline LiMn2O4 thin film cathode material prepared by polymer spray pyrolysis method for Li-ion battery

International Nuclear Information System (INIS)

Karthick, S.N.; Richard Prabhu Gnanakan, S.; Subramania, A.; Kim, Hee-Je

2010-01-01

Nanocrystalline cubic spinel lithium manganese oxide thin film was prepared by a polymer spray pyrolysis method using lithium acetate and manganese acetate precursor solution and polyethylene glycol-4000 as a polymeric binder. The substrate temperature was selected from the thermogravimetric analysis by finding the complete crystallization temperature of LiMn 2 O 4 precursor sample. The deposited LiMn 2 O 4 thin films were annealed at 450, 500 and 600 o C for 30 min. The thin film annealed at 600 o C was found to be the sufficient temperature to form high phase pure nanocrystalline LiMn 2 O 4 thin film. The formation of cubic spinel thin film was confirmed by X-ray diffraction study. Scanning electron microscopy and atomic force microscopy analysis revealed that the thin film annealed at 600 o C was found to be nanocrystalline in nature and the surface of the films were uniform without any crack. The electrochemical charge/discharge studies of the prepared LiMn 2 O 4 film was found to be better compared to the conventional spray pyrolysed thin film material.

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.

Profilometry of thin films on rough substrates by Raman spectroscopy

KAUST Repository

Ledinský, Martin

2016-12-06

Thin, light-absorbing films attenuate the Raman signal of underlying substrates. In this article, we exploit this phenomenon to develop a contactless thickness profiling method for thin films deposited on rough substrates. We demonstrate this technique by probing profiles of thin amorphous silicon stripes deposited on rough crystalline silicon surfaces, which is a structure exploited in high-efficiency silicon heterojunction solar cells. Our spatially-resolved Raman measurements enable the thickness mapping of amorphous silicon over the whole active area of test solar cells with very high precision; the thickness detection limit is well below 1 nm and the spatial resolution is down to 500 nm, limited only by the optical resolution. We also discuss the wider applicability of this technique for the characterization of thin layers prepared on Raman/photoluminescence-active substrates, as well as its use for single-layer counting in multilayer 2D materials such as graphene, MoS2 and WS2.

Profilometry of thin films on rough substrates by Raman spectroscopy

KAUST Repository

Ledinský , Martin; Paviet-Salomon, Bertrand; Vetushka, Aliaksei; Geissbü hler, Jonas; Tomasi, Andrea; Despeisse, Matthieu; De Wolf, Stefaan; Ballif  , Christophe; Fejfar, Antoní n

2016-01-01

Thin, light-absorbing films attenuate the Raman signal of underlying substrates. In this article, we exploit this phenomenon to develop a contactless thickness profiling method for thin films deposited on rough substrates. We demonstrate this technique by probing profiles of thin amorphous silicon stripes deposited on rough crystalline silicon surfaces, which is a structure exploited in high-efficiency silicon heterojunction solar cells. Our spatially-resolved Raman measurements enable the thickness mapping of amorphous silicon over the whole active area of test solar cells with very high precision; the thickness detection limit is well below 1 nm and the spatial resolution is down to 500 nm, limited only by the optical resolution. We also discuss the wider applicability of this technique for the characterization of thin layers prepared on Raman/photoluminescence-active substrates, as well as its use for single-layer counting in multilayer 2D materials such as graphene, MoS2 and WS2.

Effect of oxygen to argon flow ratio on the properties of Al-doped ZnO films for amorphous silicon thin film solar cell applications

Energy Technology Data Exchange (ETDEWEB)

Lin, Yang-Shih [Department of Materials Science and Engineering, National Chung Hsing University, Taichung 402, Taiwan, ROC (China); Lien, Shui-Yang, E-mail: syl@mdu.edu.tw [Department of Materials Science and Engineering, MingDao University, ChangHua 52345, Taiwan, ROC (China); Huang, Yung-Chuan [Department of Materials Science and Engineering, MingDao University, ChangHua 52345, Taiwan, ROC (China); Wang, Chao-Chun [Department of Materials Science and Engineering, National Chung Hsing University, Taichung 402, Taiwan, ROC (China); Liu, Chueh-Yang [Department of Materials Science and Engineering, MingDao University, ChangHua 52345, Taiwan, ROC (China); Nautiyal, Asheesh [Department of Mechanical Engineering, Yuan Ze University, 135 Yuan-Tung Road, Chungli, 320 Taoyuan, Taiwan, ROC (China); Wuu, Dong-Sing [Department of Materials Science and Engineering, National Chung Hsing University, Taichung 402, Taiwan, ROC (China); Lee, Shuo-Jun [Department of Mechanical Engineering, Yuan Ze University, 135 Yuan-Tung Road, Chungli, 320 Taoyuan, Taiwan, ROC (China)

2013-02-01

Transparent conductive oxide thin films in solar cell fabrication have attracted much attention due to their high conductivity and transmittance. In this paper, we have investigated the aluminum-doped zinc oxide (AZO) thin films prepared by radiofrequency magnetron sputtering on Asahi U-type SnO{sub 2} glass with different O{sub 2}/Ar flow ratios in vacuum chamber. Furthermore, the micro-structural, electrical, and optical properties of AZO/SnO{sub 2} films were studied. The change in O{sub 2}/Ar flow ratios is found to significantly affect the haze value, and slightly affect electrical resistivity and transmittance of the films. Afterward, the fabricated AZO thin films with different O{sub 2}/Ar flow ratios were used for building the solar cell devices. The current–voltage and external quantum efficiency characteristics were investigated for the solar cell devices. The optimized O{sub 2}/Ar flow ratio of 3 for solar device shows the best efficiency of 10.41%, and a 20% increase in short-circuit current density compared to typical Asahi solar cells. - Highlights: ► A thin Al-doped zinc oxide (AZO) film has been deposited on SnO{sub 2} substrates. ► The AZO film deposited at an O{sub 2}/Ar ratio of 3 shows low resistivity and high haze. ► The AZO film contains tiny grains that enhance light scattering. ► The amorphous silicon solar cell with the AZO layer shows a 20% increase in Jsc.

Research on fabrication technology for thin film solar cells for practical use. Survey on the commercialization analysis; Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Jitsuyoka kaiseki ni kansuru chosa kenkyu

Energy Technology Data Exchange (ETDEWEB)

Tatsuta, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

1994-12-01

This paper reports the survey results on the technological trend, safety and latest technologies of thin film solar cells in fiscal 1994. As the fabrication technology for amorphous film solar cells, three-electrode plasma CVD was surveyed as fabrication method for high-mobility materials, and hydrogen radical CVD as fabrication method for high-photostable films. Current foreign and domestic reliability tests were surveyed for reliability evaluation of solar cells. In order to ascertain the performance, efficiency, physical properties and optimum structure of polycrystalline Si thin film solar cells, previously reported test results on physical properties such as carrier concentration, carrier lifetime and mobility of films were surveyed together with device simulation results. In addition, technologies for high-efficiency CuInSe2 system and CdTe system solar cells, technologies for cost reduction and mass production, and environmental influence were surveyed. Estimation of production costs for cell modules, and safety of thin film solar cells were also surveyed.

Analysis of the High Conversion Efficiencies β-FeSi2 and BaSi2 n-i-p Thin Film Solar Cells

International Nuclear Information System (INIS)

Huang, J.Sh.; Lee, K.W.; Tseng, Y.H.

2014-01-01

Both β-FeSi 2 and BaSi 2 are silicides and have large absorption coefficients; thus they are very promising Si-based new materials for solar cell applications. In this paper, the dc I-V characteristics of n-Si/i-βFeSi 2 /p-Si and n-Si/i-BaSi 2 /p-Si thin film solar cells are investigated by solving the charge transport equations with optical generations. The diffusion current densities of free electron and hole are calculated first. Then the drift current density in the depletion regions is obtained. The total current density is the sum of diffusion and drift current densities. The conversion efficiencies are obtained from the calculated I-V curves. The optimum conversion efficiency of n-Si/i-βFeSi 2 /p-Si thin film solar cell is 27.8% and that of n-Si/i-BaSi 2 /p-Si thin film solar cell is 30.4%, both are larger than that of Si n-i-p solar cell (η is 20.6%). These results are consistent with their absorption spectrum. The calculated conversion efficiency of Si n-i-p solar cell is consistent with the reported researches. Therefore, these calculation results are valid in this work.

Analysis of the High Conversion Efficiencies β-FeSi2 and BaSi2 n-i-p Thin Film Solar Cells

Directory of Open Access Journals (Sweden)

Jung-Sheng Huang

2014-01-01

Full Text Available Both β-FeSi2 and BaSi2 are silicides and have large absorption coefficients; thus they are very promising Si-based new materials for solar cell applications. In this paper, the dc I-V characteristics of n-Si/i-βFeSi2/p-Si and n-Si/i-BaSi2/p-Si thin film solar cells are investigated by solving the charge transport equations with optical generations. The diffusion current densities of free electron and hole are calculated first. Then the drift current density in the depletion regions is obtained. The total current density is the sum of diffusion and drift current densities. The conversion efficiencies are obtained from the calculated I-V curves. The optimum conversion efficiency of n-Si/i-βFeSi2/p-Si thin film solar cell is 27.8% and that of n-Si/i-BaSi2/p-Si thin film solar cell is 30.4%, both are larger than that of Si n-i-p solar cell (η is 20.6%. These results are consistent with their absorption spectrum. The calculated conversion efficiency of Si n-i-p solar cell is consistent with the reported researches. Therefore, these calculation results are valid in this work.

Experimental studies of thin films deposition by magnetron sputtering method for CIGS solar cell fabrication

Science.gov (United States)

Gułkowski, Sławomir; Krawczak, Ewelina

2017-10-01

Among a variety of the thin film solar cell technologies of second generation, copper-indium-gallium-diselenide device (CIGS) with the latest highest lab cell efficiency record of 22.4 % seems to be the most promising for the power generation. This is partly due to the advantages of using low cost films of few microns thick not only as a metallic contacts but also as a main structure of the solar cell consisted of high quality semiconductor layers. This paper reports the experimental studies of the CIGS absorber formation on Soda Lime Glass substrate covered by thin molybdenum film as a back contact layer. All structures were deposited with the use of magnetron sputtering method only. Technological parameters of the deposition process such as deposition power, pressure and deposition time were optimized for each layer of the structure. Mo back contact was examined in terms of resistivity. EDS measurements were carried out to verify stoichiometric composition of CIGS absorber. Thin film of Al was used as a top contact in order to examine the quality of p-n junction. The I-V electrical characteristic of the p-n junction was analysed in terms of solar cell application.

Application of plasma silicon nitride to crystalline thin-film silicon solar cells. Paper

Energy Technology Data Exchange (ETDEWEB)

Schmidt, J.; Oberbeck, L.; Rinke, T.J.; Berge, C.; Bergmann, R.B.

2002-07-01

We use plasma-enhanced chemical vapour deposition to deposit silicon nitride (SiN{sub x}) films at low temperature(400 C) onto the front surface of two different types of crystalline thin-film Si solar cells. The silicon nitride acts as an excellent antireflection coating on Si and provides a very high degree of electronic surface passivation over a wide range of compositions, including near-stoichiometric and Si-rich SiN{sub x}. Application of stoichiometric SiN{sub x} to non-textured thin-film cells, epitaxially grown at low temperature by ion-assisted deposition onto a monocrystalline Si substrate, results in an open-circuit voltage of 622 mV, a short-circuit current density of 26.6 mA/cm{sup 2} and an efficiency of 12.7%. It is shown that the SiN{sub x}-passivated in-situ grown n{sup +}-emitter of this cell type allows to reach open-circuit voltages of up to 667 mV. Silicon-rich SiN{sub x} is applied to the phosphorus-diffused n{sup +}-emitter of a textured thin-film cell on a glass superstrate fabricated by layer-transfer. The emitter saturation current density of these cells is only 40-64 fA/cm{sup 2}, which allows for open-circuit voltages of up to 699 mV. An impressively high open-circuit voltage of 638 mV and a short-circuit current density of 32.0 mA/cm{sup 2} are obtained for a 25 {mu}m thick SiN{sub x}-passivated, random pyramid-textured transfer cell. A transfer cell efficiency of 15.3% is independently confirmed.

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

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.

Tunable silver-shell dielectric core nano-beads array for thin-film solar cell application

Energy Technology Data Exchange (ETDEWEB)

Chou Chau, Yuan-Fong, E-mail: a0920146302@gmail.com, E-mail: chou.fong@ubd.edu.bn; Lim, Chee Ming [Universiti Brunei Darussalam, Centre for Advanced Material and Energy Sciences (Brunei) (Brunei Darussalam); Chiang, Chien-Ying [National Taipei University of Technology, Department of Electro-Optical Engineering (China); Voo, Nyuk Yoong; Muhammad Idris, Nur Syafi’ie; Chai, Siew Ung [Universiti Brunei Darussalam, Centre for Advanced Material and Energy Sciences (Brunei) (Brunei Darussalam)

2016-04-15

The absorbance spectra of thin-film solar cells (TFSCs) can be enhanced by constructing the tunable periodic Ag-shell nano-bead (PASNB) arrays in the active material. In this paper, we investigated a plasmonic thin-film solar cell (TFSC) which composed of the arrays of PASNB deposited onto a crystalline silicon layer. By performing three-dimensional finite element method, we demonstrate that near field coupling among the PASNB arrays results in SPR modes with enhanced absorbance and field intensity. The proposed structure can significantly enhance the plasmonic activity in a wide range of incident light and enlarge working wavelength of absorbance in the range of near-UV, visible and near-infrared. We show that the sensitivity of the PASNB arrays reveals a linear relationship with the thickness of Ag-shell nano-bead (ASNB) for both the anti-bonding and bonding modes in the absorbance spectra. The broadband of absorbance spectra could be expanded as a wide range by varying the thickness of ASNB while the particle size is kept constant. Simulation results suggest this alternative scheme to the design and improvements on plasmonic enhanced TFSCs can be extended to other nanophotonic applications.

Temperature responsive functional polymeric thin films obtained by matrix assisted pulsed laser evaporation for cells attachment–detachment study

Energy Technology Data Exchange (ETDEWEB)

Rusen, L. [NILPRP, National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-16, RO-077125 Magurele, Bucharest (Romania); Dinca, V., E-mail: dinali@nipne.ro [NILPRP, National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-16, RO-077125 Magurele, Bucharest (Romania); Mitu, B. [NILPRP, National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-16, RO-077125 Magurele, Bucharest (Romania); Mustaciosu, C. [Horia Hulubei National Institute of Physics and Nuclear Engineering, IFIN HH, Magurele, Bucharest (Romania); Dinescu, M. [NILPRP, National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-16, RO-077125 Magurele, Bucharest (Romania)

2014-05-01

Multifunctional thin films used as thermoresponsive substrate for engineering cell sheets represent an important area in tissue engineering. As the morphology and the chemical characteristics of the thin films directly control their interaction with cells, it is important to correlate these characteristics with the biological answer. In this study, thermally sensitive poly(N-isopropylacrylamide), (pNIPAAm) thin films were prepared by matrix assisted pulsed laser evaporation and utilized in L929 cell adhesion and detachment studies. Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM) were used to determine the pNIPAAm thin films chemical and morphological characteristics. The FTIR data demonstrated that the functional groups in the MAPLE-deposited films remained intact for fluences in the range of 200–600 mJ cm{sup −2}. Within this fluence range, the AFM topographical studies showed that the roughness of the coatings was dependent on laser fluence and the obtained surfaces were characterized by a granular aspect. L929 cell viability studies onto the pNIPAAm coatings showed little or no toxic effect for fluences below 600 mJ cm{sup −2}, while for higher fluences, viability was decreased with more than 50%. The adhesion and detachment of the cell was found to be mainly dependent on the film surface morphology.

Mesoscale simulations of confined Nafion thin films

Science.gov (United States)

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

2017-12-01

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

Solution-processed In2S3 buffer layer for chalcopyrite thin film solar cells

Science.gov (United States)

Wang, Lan; Lin, Xianzhong; Ennaoui, Ahmed; Wolf, Christian; Lux-Steiner, Martha Ch.; Klenk, Reiner

2016-02-01

We report a route to deposit In2S3 thin films from air-stable, low-cost molecular precursor inks for Cd-free buffer layers in chalcopyrite-based thin film solar cells. Different precursor compositions and processing conditions were studied to define a reproducible and robust process. By adjusting the ink properties, this method can be applied in different printing and coating techniques. Here we report on two techniques, namely spin-coating and inkjet printing. Active area efficiencies of 12.8% and 12.2% have been achieved for In2S3-buffered solar cells respectively, matching the performance of CdS-buffered cells prepared with the same batch of absorbers.

Polymorphous silicon thin films produced in dusty plasmas: application to solar cells

International Nuclear Information System (INIS)

Roca i Cabarrocas, Pere; Chaabane, N; Kharchenko, A V; Tchakarov, S

2004-01-01

We summarize our current understanding of the optimization of PIN solar cells produced by plasma enhanced chemical vapour deposition from silane-hydrogen mixtures. To increase the deposition rate, the discharge is operated under plasma conditions close to powder formation, where silicon nanocrystals contribute to the deposition of so-called polymorphous silicon thin films. We show that the increase in deposition rate can be achieved via an accurate control of the plasma parameters. However, this also results in a highly defective interface in the solar cells due to the bombardment of the P-layer by positively charged nanocrystals during the deposition of the I-layer. We show that decreasing the ion energy by increasing the total pressure or by using silane-helium mixtures allows us to increase both the deposition rate and the solar cells efficiency, as required for cost effective thin film photovoltaics

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.

MOCVD ZnO/Screen Printed Ag Back Reflector for Flexible Thin Film Silicon Solar Cell Application

Directory of Open Access Journals (Sweden)

Amornrat Limmanee

2014-01-01

Full Text Available We have prepared Ag back electrode by screen printing technique and developed MOCVD ZnO/screen printed Ag back reflector for flexible thin film silicon solar cell application. A discontinuity and poor contact interface between the MOCVD ZnO and screen printed Ag layers caused poor open circuit voltage (Voc and low fill factor (FF; however, an insertion of a thin sputtered ZnO layer at the interface could solve this problem. The n type hydrogenated amorphous silicon (a-Si:H film is preferable for the deposition on the surface of MOCVD ZnO film rather than the microcrystalline film due to its less sensitivity to textured surface, and this allowed an improvement in the FF. The n-i-p flexible amorphous silicon solar cell using the MOCVD ZnO/screen printed Ag back reflector showed an initial efficiency of 6.2% with Voc=0.86 V, Jsc=12.4 mA/cm2, and FF = 0.58 (1 cm2. The identical quantum efficiency and comparable performance to the cells using conventional sputtered Ag back electrode have verified the potential of the MOCVD ZnO/screen printed Ag back reflector and possible opportunity to use the screen printed Ag thick film for flexible thin film silicon solar cells.

Biocompatibility of Hydrogen-Diluted Amorphous Silicon Carbide Thin Films for Artificial Heart Valve Coating

Science.gov (United States)

Rizal, Umesh; Swain, Bhabani S.; Rameshbabu, N.; Swain, Bibhu P.

2018-01-01

Amorphous silicon carbide (a-SiC:H) thin films were synthesized using trichloromethylsilane by a hot wire chemical vapor deposition process. The deposited films were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, x-ray diffraction and x-ray photoelectron spectroscopy to confirm its chemical bonding, structural network and composition of the a-SiC:H films. The optical microscopy images reveal that hydrogen dilution increased the surface roughness and pore density of a-SiC:H thin film. The Raman spectroscopy and FTIR spectra reveal chemical network consisting of Si-Si, C-C and Si-C bonds, respectively. The XRD spectroscopy and Raman spectroscopy indicate a-SiC:H still has short-range order. In addition, in vitro cytotoxicity test ensures the behavior of cell-semiconductor hybrid to monitor the proper coordination. The live-dead assays and MTT assay reveal an increase in green nucleus cell, and cell viability is greater than 88%, respectively, showing non-toxic nature of prepared a-SiC:H film. Moreover, the result indicated by direct contact assay, and cell prefers to adhere and proliferate on a-SiC:H thin films having a positive effect as artificial heart valve coating material.

Thin films of lithium manganese oxide spinel as cathode materials for secondary lithium batteries

International Nuclear Information System (INIS)

Shui, J.L.; Jiang, G.S.; Xie, S.; Chen, C.H.

2004-01-01

The miniaturization of rechargeable lithium-ion batteries requires high quality thin-film electrodes. Electrostatic spray deposition (ESD) technique was used to fabricate LiMn 2 O 4 thin-film electrodes with three different morphologies: sponge-like porous, fractal-like porous, and dense structures. X-ray diffraction (XRD) and scanning electron microscopy were used to analyze the structures of the electrodes. These electrodes were made into coin cells against metallic lithium for electrochemical characterization. Galvanostatic cycling of the cells revealed different rate capability for the cells with LiMn 2 O 4 electrodes of different morphologies. It is found that the cells with LiMn 2 O 4 electrodes of porous, especially the sponge-like porous, morphology better rate capability than those with dense LiMn 2 O 4 electrodes. Electrochemical impedance spectroscopy (EIS) study indicates that the large surface area of the porous electrodes should be attributed to the smaller interfacial resistance and better rate capability

Quantifying oxygen in paper-based cell cultures with luminescent thin film sensors.

Science.gov (United States)

Boyce, Matthew W; Kenney, Rachael M; Truong, Andrew S; Lockett, Matthew R

2016-04-01

Paper-based scaffolds are an attractive material for generating 3D tissue-like cultures because paper is readily available and does not require specialized equipment to pattern, cut, or use. By controlling the exchange of fresh culture medium with the paper-based scaffolds, we can engineer diffusion-dominated environments similar to those found in spheroids or solid tumors. Oxygen tension directly regulates cellular phenotype and invasiveness through hypoxia-inducible transcription factors and also has chemotactic properties. To date, gradients of oxygen generated in the paper-based cultures have relied on cellular response-based readouts. In this work, we prepared a luminescent thin film capable of quantifying oxygen tensions in apposed cell-containing paper-based scaffolds. The oxygen sensors, which are polystyrene films containing a Pd(II) tetrakis(pentafluorophenyl)porphyrin dye, are photostable, stable in culture conditions, and not cytotoxic. They have a linear response for oxygen tensions ranging from 0 to 160 mmHg O2, and a Stern-Volmer constant (K sv) of 0.239 ± 0.003 mmHg O2 (-1). We used these oxygen-sensing films to measure the spatial and temporal changes in oxygen tension for paper-based cultures containing a breast cancer line that was engineered to constitutively express a fluorescent protein. By acquiring images of the oxygen-sensing film and the fluorescently labeled cells, we were able to approximate the oxygen consumption rates of the cells in our cultures.

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.

Electrical Properties of Al, Ag, Cu, Ti and SS Thin Film for Electrode of Solar Cell

International Nuclear Information System (INIS)

Bambang Siswanto; Wirjoadi; Sudjatmoko; Tjipto Sujitno

2003-01-01

The Al, Ag, Cu, Ti and SS materials were deposited on the surface of glass substrate using plasma DC sputtering technique. The deposition process was done with the following plasma parameters : deposition time, gas pressure and substrate temperature with the aim to obtain a good conductance of thin films. Variation of substrate deposition time was 1 - 15 minutes, gas pressure was 5x10 -2 - 7x10 -2 torr and of temperature was 100 - 300 o C. The resistance measurement has been done by four points probes and the conductivity was calculated using mathematic formulation. It was obtained that the minimum resistance in the order of R = 0.07 Ω, was found at Ag materials and this was obtained at the following plasma parameters : deposition time 15 minutes, gas pressure 6x10 -2 torr and temperature 300 o C, while, the resistance of : Cu, Al, Ti and SS materials were R = 0.13 Ω, R = 450 Ω, R = 633 Ω, R = 911 Ω respectively, It could be concluded that the Ag thin film has a minimum resistance, high conductivity compared to the other materials Al, Cu, Ti and SS. Ag is therefore the suitable material for applying as electrode of solar cell. (author)

Synthesis and characterization of DC magnetron sputtered nano structured molybdenum thin films

Energy Technology Data Exchange (ETDEWEB)

Rondiya, S. R.; Rokade, A. V.; Jadhavar, A. A.; Pandharkar, S. M.; Kulkarni, R. R.; Karpe, S. D.; Diwate, K. D. [School of Energy Studies, Savitribai Phule Pune University, Pune 411007 (India); Jadkar, S. R., E-mail: sandesh@physics.unipune.ac.in [Department of Physics, Savitribai Phule Pune University, Pune 411007 (India)

2016-04-13

Molybdenum (Mo) thin films were deposited on corning glass (#7059) substrates using DC magnetron sputtering system. The effect of substrate temperature on the structural, morphology and topological properties have been investigated. Films were characterized by variety of techniques such as low angle x-ray diffraction (low angle XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM). The low angle XRD analysis revealed that the synthesized Mo films are nanocrystalline having cubic crystal structure with (110) preferential orientation. The microstructure of the deposited Mo thin films observed with FE-SEM images indicated that films are homogeneous and uniform with randomly oriented leaf shape morphology. The AFM analysis shows that with increase in substrate temperature the rms roughness of Mo films increases. The obtained results suggest that the synthesized nanostructured Mo thin films have potential application as a back contact material for high efficiency solar cells like CdTe, CIGS, CZTS etc.

Frequency-domain Harman technique for rapid characterization of bulk and thin film thermoelectric materials

Science.gov (United States)

Moran, Samuel

Nanostructured thermoelectrics, often in the form of thin films, may potentially improve the generally poor efficiency of bulk thermoelectric power generators and coolers. In order to characterize the efficiency of these new materials it is necessary to measure their thermoelectric figure of merit, ZT. The only direct measurement of ZT is based on the Harman technique and relies on measuring the voltage drop across a sample subjected to a passing continuous current. Application of this technique to thin films is currently carried out as a time-domain measurement of the voltage as the thermal component decays after switching off an applied voltage. This work develops a technique for direct simultaneous measurement of figure of merit and Seebeck coefficient from the harmonic response of a thermoelectric material under alternating current excitation. A thermocouple mounted on the top surface measures voltage across the device as the frequency of the applied voltage is varied. A thermal model allows the sample thermal conductivity to also be determined and shows good agreement with measurements. This technique provides improved signal-to-noise ratio and accuracy compared to time-domain ZT measurements for comparable conditions while simultaneously measuring Seebeck coefficient. The technique is applied to both bulk and thin film thermoelectric samples.

Preparation of Zinc Oxide (ZnO) Thin Film as Transparent Conductive Oxide (TCO) from Zinc Complex Compound on Thin Film Solar Cells: A Study of O2 Effect on Annealing Process

Science.gov (United States)

Muslih, E. Y.; Kim, K. H.

2017-07-01

Zinc oxide (ZnO) thin film as a transparent conductive oxide (TCO) for thin film solar cell application was successfully prepared through two step preparations which consisted of deposition by spin coating at 2000 rpm for 10 second and followed by annealing at 500 °C for 2 hours under O2 and ambient atmosphere. Zinc acetate dehydrate was used as a precursor which dissolved in ethanol and acetone (1:1 mol) mixture in order to make a zinc complex compound. In this work, we reported the O2 effect, reaction mechanism, structure, morphology, optical and electrical properties. ZnO thin film in this work shows a single phase of wurtzite, with n-type semiconductor and has band gap, carrier concentration, mobility, and resistivity as 3.18 eV, 1.21 × 10-19cm3, 11 cm2/Vs, 2.35 × 10-3 Ωcm respectively which is suitable for TCO at thin film solar cell.

Multiscale Computational Fluid Dynamics: Methodology and Application to PECVD of Thin Film Solar Cells

Directory of Open Access Journals (Sweden)

Marquis Crose

2017-02-01

Full Text Available This work focuses on the development of a multiscale computational fluid dynamics (CFD simulation framework with application to plasma-enhanced chemical vapor deposition of thin film solar cells. A macroscopic, CFD model is proposed which is capable of accurately reproducing plasma chemistry and transport phenomena within a 2D axisymmetric reactor geometry. Additionally, the complex interactions that take place on the surface of a-Si:H thin films are coupled with the CFD simulation using a novel kinetic Monte Carlo scheme which describes the thin film growth, leading to a multiscale CFD model. Due to the significant computational challenges imposed by this multiscale CFD model, a parallel computation strategy is presented which allows for reduced processing time via the discretization of both the gas-phase mesh and microscopic thin film growth processes. Finally, the multiscale CFD model has been applied to the PECVD process at industrially relevant operating conditions revealing non-uniformities greater than 20% in the growth rate of amorphous silicon films across the radius of the wafer.

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

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

Science.gov (United States)

Jankowski, Alan F.; Schmid, Anthony P.

2000-01-01

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

Research and development of CdTe based thin film PV solar cells

Science.gov (United States)

Diso, Dahiru Garba

The motivation behind this research is to bring cheap, low-cost and clean energy technologies to the society. Colossal use of fossil fuel has created noticeable pollution problems contributing to climate change and health hazards. Silicon based solar cells have dominated the market but it is cost is high due to the manufacturing process. Therefore, the way forward is to develop thin films solar cells using low-cost attractive materials, grown by cheaper, scalable and manufacturable techniques.The aim and objectives of this work is to develop low-cost, high efficiency solar cell using electrodeposition (ED) technique. The material layers include CdS and ZnTe as the window materials, while the absorber material is CdTe. Fabricating a suitable devices for solar energy conversion (i.e. glass/conducting glass/window material/absorber material/metal) structure. Traditional way of fabricating this structure is to grow window material (CdS) using chemical bath deposition (CBD) and absorber material (CdTe) using electrodeposition. However, CBD is a batch process and therefore creates large volumes of Cd-containing waste solutions each time adding high cost in manufacturing process. This research programme is therefore on development of an "All ED-solar cells" structure.Material studies were carried out using photoelectrochemical (PEC) studies, UV-Vis spectrophotometry, X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Furthermore, the electrical characterisation of fully fabricated devices was performed using current-voltage (I-V) and capacitance-voltage (C-V) measurements.This research programme has demonstrated that CdS and ZnTe window materials can be electrodeposited and used in thin film solar cell devices. The CdS electrolytic bath can be used for a period of 7 months without discarding it like in the CBD process which usually has life

Transparent conducting oxide layers for thin film silicon solar cells

NARCIS (Netherlands)

Rath, J.K.; Liu, Y.; de Jong, M.M.; de Wild, J.; Schuttauf, J.A.; Brinza, M.; Schropp, R.E.I.

2009-01-01

Texture etching of ZnO:1%Al layers using diluted HCl solution provides excellent TCOs with crater type surface features for the front contact of superstrate type of thin film silicon solar cells. The texture etched ZnO:Al definitely gives superior performance than Asahi SnO2:F TCO in case of

Study of Interfacial Interactions Using Thin Film Surface Modification: Radiation and Oxidation Effects in Materials

International Nuclear Information System (INIS)

2014-01-01

Interfaces play a key role in dictating the long-term stability of materials under the influence of radiation and high temperatures. For example, grain boundaries affect corrosion by way of providing kinetically favorable paths for elemental diffusion, but they can also act as sinks for defects and helium generated during irradiation. Likewise, the retention of high-temperature strength in nanostructured, oxide-dispersion strengthened steels depends strongly on the stoichiometric and physical stability of the (Y, Ti)-oxide particles/matrix interface under radiation and high temperatures. An understanding of these interfacial effects at a fundamental level is important for the development of materials for extreme environments of nuclear reactors. The goal of this project is to develop an understanding stability of interfaces by depositing thin films of materials on substrates followed by ion irradiation of the film-substrate system at elevated temperatures followed by post-irradiation oxidation treatments. Specifically, the research will be performed by depositing thin films of yttrium and titanium (~500 nm) on Fe-12%Cr binary alloy substrate. Y and Ti have been selected as thin-film materials because they form highly stable protective oxides layers. The Fe-12%Cr binary alloy has been selected because it is representative of ferritic steels that are widely used in nuclear systems. The absence of other alloying elements in this binary alloy would allow for a clearer examination of structures and compositions that evolve during high-temperature irradiations and oxidation treatments. The research is divided into four specific tasks: (1) sputter deposition of 500 nm thick films of Y and Ti on Fe-12%Cr alloy substrates, (2) ion irradiation of the film-substrate system with 2MeV protons to a dose of 2 dpa at temperatures of 300°C, 500°C, and 700°C, (3) oxidation of as-deposited and ion-irradiated samples in a controlled oxygen environment at 500°C and 700°C, (4

Reliable wet-chemical cleaning of natively oxidized high-efficiency Cu(In,Ga)Se2 thin-film solar cell absorbers

Science.gov (United States)

Lehmann, Jascha; Lehmann, Sebastian; Lauermann, Iver; Rissom, Thorsten; Kaufmann, Christian A.; Lux-Steiner, Martha Ch.; Bär, Marcus; Sadewasser, Sascha

2014-12-01

Currently, Cu-containing chalcopyrite-based solar cells provide the highest conversion efficiencies among all thin-film photovoltaic (PV) technologies. They have reached efficiency values above 20%, the same performance level as multi-crystalline silicon-wafer technology that dominates the commercial PV market. Chalcopyrite thin-film heterostructures consist of a layer stack with a variety of interfaces between different materials. It is the chalcopyrite/buffer region (forming the p-n junction), which is of crucial importance and therefore frequently investigated using surface and interface science tools, such as photoelectron spectroscopy and scanning probe microscopy. To ensure comparability and validity of the results, a general preparation guide for "realistic" surfaces of polycrystalline chalcopyrite thin films is highly desirable. We present results on wet-chemical cleaning procedures of polycrystalline Cu(In1-xGax)Se2 thin films with an average x = [Ga]/([In] + [Ga]) = 0.29, which were exposed to ambient conditions for different times. The hence natively oxidized sample surfaces were etched in KCN- or NH3-based aqueous solutions. By x-ray photoelectron spectroscopy, we find that the KCN treatment results in a chemical surface structure which is - apart from a slight change in surface composition - identical to a pristine as-received sample surface. Additionally, we discover a different oxidation behavior of In and Ga, in agreement with thermodynamic reference data, and we find indications for the segregation and removal of copper selenide surface phases from the polycrystalline material.

Initial Study on Thin Film Preparation of Carbon Nanodots Composites as Luminescence Material

Science.gov (United States)

Iskandar, F.; Aimon, A. H.; Akmaluddin, A. R.; Nuryadin, B. W.; Abdullah, M.

2016-08-01

Nowadays, the developments of phosphors materials require elements without noble metals and simple production process. Carbon nanodots (C-dots) are one of phosphor materials with wide range of emission band, and high biocompatibility. In this research thin film carbon nanodots composite have been prepared by spin coating method. Prior deposition, powder carbon nanodots were synthesized from a mixture of commercial urea as the nitrogen sources and citric acid as a carbon source by using hydrothermal and microwave-assisted heating method. The prepared powder was dispersed in transparent epoxy resin and then coated on glass substrate. The photoluminescence result for sample with 0.035 g citric acid exhibited an intense, single, homogeneous and broad spectrum with yellowish emission upon excitation at 365 nm. The Fourier Transform Infrared Spectroscopy (FTIR) result showed the existences of C=C, C-H, C=O, N-H and O-H functional groups which confirmed the quality of the sample. Further, based on UV-Vis measurement, the prepared thin film was highly transparent (transmittance 90%) with estimated film thickness around 764 nm. This result may open an opportunity for optoelectronic devices.

Initial Study on Thin Film Preparation of Carbon Nanodots Composites as Luminescence Material

International Nuclear Information System (INIS)

Iskandar, F; Aimon, A H; Akmaluddin, A R; Abdullah, M; Nuryadin, B W

2016-01-01

Nowadays, the developments of phosphors materials require elements without noble metals and simple production process. Carbon nanodots (C-dots) are one of phosphor materials with wide range of emission band, and high biocompatibility. In this research thin film carbon nanodots composite have been prepared by spin coating method. Prior deposition, powder carbon nanodots were synthesized from a mixture of commercial urea as the nitrogen sources and citric acid as a carbon source by using hydrothermal and microwave-assisted heating method. The prepared powder was dispersed in transparent epoxy resin and then coated on glass substrate. The photoluminescence result for sample with 0.035 g citric acid exhibited an intense, single, homogeneous and broad spectrum with yellowish emission upon excitation at 365 nm. The Fourier Transform Infrared Spectroscopy (FTIR) result showed the existences of C=C, C-H, C=O, N-H and O-H functional groups which confirmed the quality of the sample. Further, based on UV-Vis measurement, the prepared thin film was highly transparent (transmittance 90%) with estimated film thickness around 764 nm. This result may open an opportunity for optoelectronic devices. (paper)

Material engineering to fabricate rare earth erbium thin films for exploring nuclear energy sources

Science.gov (United States)

Banerjee, A.; Abhilash, S. R.; Umapathy, G. R.; Kabiraj, D.; Ojha, S.; Mandal, S.

2018-04-01

High vacuum evaporation and cold-rolling techniques to fabricate thin films of the rare earth lanthanide-erbium have been discussed in this communication. Cold rolling has been used for the first time to successfully fabricate films of enriched and highly expensive erbium metal with areal density in the range of 0.5-1.0 mg/cm2. The fabricated films were used as target materials in an advanced nuclear physics experiment. The experiment was designed to investigate isomeric states in the heavy nuclei mass region for exploring physics related to nuclear energy sources. The films fabricated using different techniques varied in thickness as well as purity. Methods to fabricate films with thickness of the order of 0.9 mg/cm2 were different than those of 0.4 mg/cm2 areal density. All the thin films were characterized using multiple advanced techniques to accurately ascertain levels of contamination as well as to determine their exact surface density. Detailed fabrication methods as well as characterization techniques have been discussed.

Thin Film Approaches to the SRF Cavity Problem Fabrication and Characterization of Superconducting Thin Films

Energy Technology Data Exchange (ETDEWEB)

Beringer, Douglas [College of William and Mary, Williamsburg, VA (United States)

2017-08-01

Superconducting Radio Frequency (SRF) cavities are responsible for the acceleration of charged particles to relativistic velocities in most modern linear accelerators, such as those employed at high-energy research facilities like Thomas Jefferson National Laboratory’s CEBAF and the LHC at CERN. Recognizing SRF as primarily a surface phenomenon enables the possibility of applying thin films to the interior surface of SRF cavities, opening a formidable tool chest of opportunities by combining and designing materials that offer greater performance benefit. Thus, while improvements in radio frequency cavity design and refinements in cavity processing techniques have improved accelerator performance and efficiency – 1.5 GHz bulk niobium SRF cavities have achieved accelerating gradients in excess of 35 MV/m – there exist fundamental material bounds in bulk superconductors limiting the maximally sustained accelerating field gradient (≈ 45 MV/m for Nb) where inevitable thermodynamic breakdown occurs. With state of the art Nb based cavity design fast approaching these theoretical limits, novel material innovations must be sought in order to realize next generation SRF cavities. One proposed method to improve SRF performance is to utilize thin film superconducting-insulating-superconducting (SIS) multilayer structures to effectively magnetically screen a bulk superconducting layer such that it can operate at higher field gradients before suffering critically detrimental SRF losses. This dissertation focuses on the production and characterization of thin film superconductors for such SIS layers for radio frequency applications. Correlated studies on structure, surface morphology and superconducting properties of epitaxial Nb and MgB2 thin films are presented.

Ecofriendly and Nonvacuum Electrostatic Spray-Assisted Vapor Deposition of Cu(In,Ga)(S,Se)2 Thin Film Solar Cells.

Science.gov (United States)

Hossain, Md Anower; Wang, Mingqing; Choy, Kwang-Leong

2015-10-14

Chalcopyrite Cu(In,Ga)(S,Se)2 (CIGSSe) thin films have been deposited by a novel, nonvacuum, and cost-effective electrostatic spray-assisted vapor deposition (ESAVD) method. The generation of a fine aerosol of precursor solution, and their controlled deposition onto a molybdenum substrate, results in adherent, dense, and uniform Cu(In,Ga)S2 (CIGS) films. This is an essential tool to keep the interfacial area of thin film solar cells to a minimum value for efficient charge separation as it helps to achieve the desired surface smoothness uniformity for subsequent cadmium sulfide and window layer deposition. This nonvacuum aerosol based approach for making the CIGSSe film uses environmentally benign precursor solution, and it is cheaper for producing solar cells than that of the vacuum-based thin film solar technology. An optimized CIGSSe thin film solar cell with a device configuration of molybdenum-coated soda-lime glass substrate/CIGSSe/CdS/i-ZnO/AZO shows the photovoltaic (j-V) characteristics of Voc=0.518 V, jsc=28.79 mA cm(-2), fill factor=64.02%, and a promising power conversion efficiency of η=9.55% under simulated AM 1.5 100 mW cm(-2) illuminations, without the use of an antireflection layer. This demonstrates the potential of ESAVD deposition as a promising alternative approach for making thin film CIGSSe solar cells at a lower cost.

Solution-processed In2S3 buffer layer for chalcopyrite thin film solar cells

OpenAIRE

Wang Lan; Lin Xianzhong; Ennaoui Ahmed; Wolf Christian; Lux-Steiner Martha Ch.; Klenk Reiner

2016-01-01

We report a route to deposit In2S3 thin films from air-stable, low-cost molecular precursor inks for Cd-free buffer layers in chalcopyrite-based thin film solar cells. Different precursor compositions and processing conditions were studied to define a reproducible and robust process. By adjusting the ink properties, this method can be applied in different printing and coating techniques. Here we report on two techniques, namely spin-coating ...

A Confined Fabrication of Perovskite Quantum Dots in Oriented MOF Thin Film.

Science.gov (United States)

Chen, Zheng; Gu, Zhi-Gang; Fu, Wen-Qiang; Wang, Fei; Zhang, Jian

2016-10-26

Organic-inorganic hybrid lead organohalide perovskites are inexpensive materials for high-efficiency photovoltaic solar cells, optical properties, and superior electrical conductivity. However, the fabrication of their quantum dots (QDs) with uniform ultrasmall particles is still a challenge. Here we use oriented microporous metal-organic framework (MOF) thin film prepared by liquid phase epitaxy approach as a template for CH 3 NH 3 PbI 2 X (X = Cl, Br, and I) perovskite QDs fabrication. By introducing the PbI 2 and CH 3 NH 3 X (MAX) precursors into MOF HKUST-1 (Cu 3 (BTC) 2 , BTC = 1,3,5-benzene tricarboxylate) thin film in a stepwise approach, the resulting perovskite MAPbI 2 X (X = Cl, Br, and I) QDs with uniform diameters of 1.5-2 nm match the pore size of HKUST-1. Furthermore, the photoluminescent properties and stability in the moist air of the perovskite QDs loaded HKUST-1 thin film were studied. This confined fabrication strategy demonstrates that the perovskite QDs loaded MOF thin film will be insensitive to air exposure and offers a novel means of confining the uniform size of the similar perovskite QDs according to the oriented porous MOF materials.

Epitaxial Bi2 FeCrO6 Multiferroic Thin Film as a New Visible Light Absorbing Photocathode Material.

Science.gov (United States)

Li, Shun; AlOtaibi, Bandar; Huang, Wei; Mi, Zetian; Serpone, Nick; Nechache, Riad; Rosei, Federico

2015-08-26

Ferroelectric materials have been studied increasingly for solar energy conversion technologies due to the efficient charge separation driven by the polarization induced internal electric field. However, their insufficient conversion efficiency is still a major challenge. Here, a photocathode material of epitaxial double perovskite Bi(2) FeCrO(6) multiferroic thin film is reported with a suitable conduction band position and small bandgap (1.9-2.1 eV), for visible-light-driven reduction of water to hydrogen. Photoelectrochemical measurements show that the highest photocurrent density up to -1.02 mA cm(-2) at a potential of -0.97 V versus reversible hydrogen electrode is obtained in p-type Bi(2) FeCrO(6) thin film photocathode grown on SrTiO(3) substrate under AM 1.5G simulated sunlight. In addition, a twofold enhancement of photocurrent density is obtained after negatively poling the Bi(2) FeCrO(6) thin film, as a result of modulation of the band structure by suitable control of the internal electric field gradient originating from the ferroelectric polarization in the Bi(2) FeCrO(6) films. The findings validate the use of multiferroic Bi(2) FeCrO(6) thin films as photocathode materials, and also prove that the manipulation of internal fields through polarization in ferroelectric materials is a promising strategy for the design of improved photoelectrodes and smart devices for solar energy conversion. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.