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Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Amorphous silicon thin film transistor as nonvolatile device.  

E-Print Network [OSTI]

particles before loaded into the deposition chamber. 2.2.2. Equipment for Plasma Processes Plasma-Enhanced Chemical Vapor...: Dr. Yue Kuo n-channel and p-channel amorphous-silicon thin-film transistors (a-Si:H TFTs) with copper electrodes prepared by a novel plasma etching process have been fabricated and studied. Their characteristics are similar to those of TFTs...

Nominanda, Helinda

2008-10-10T23:59:59.000Z

2

Optimization of the absorption efficiency of an amorphous-silicon thin-film tandem solar cell  

E-Print Network [OSTI]

Optimization of the absorption efficiency of an amorphous-silicon thin-film tandem solar cell-wave approach was used to compute the plane-wave absorptance of a thin-film tandem solar cell with a metallic­4]. In this context, a basic idea is to periodically texture the metallic back reflector of a thin-film solar cell

3

Enhanced quantum efficiency of amorphous silicon thin film solar cells with the inclusion of a rear-reflector thin film  

SciTech Connect (OSTI)

We investigated the growth mechanism of amorphous silicon thin films by implementing hot-wire chemical vapor deposition and fabricated thin film solar cell devices. The fabricated cells showed efficiencies of 7.5 and 8.6% for the samples without and with the rear-reflector decomposed by sputtering, respectively. The rear-reflector enhances the quantum efficiency in the infrared spectral region from 550 to 750?nm. The more stable quantum efficiency of the sample with the inclusion of a rear-reflector than the sample without the rear-reflector due to the bias effect is related to the enhancement of the short circuit current.

Park, Seungil [Department of Mechanical Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Energy Conversions Technology Center, Korea Institute of Industrial Technology, Cheonan 331-825 (Korea, Republic of); Yong Ji, Hyung; Jun Kim, Myeong; Hyeon Peck, Jong [Energy Conversions Technology Center, Korea Institute of Industrial Technology, Cheonan 331-825 (Korea, Republic of); Kim, Keunjoo, E-mail: kimk@chonbuk.ac.kr [Department of Mechanical Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

2014-02-17T23:59:59.000Z

4

Study of plasma enhanced chemical vapor deposition of boron-doped hydrogenated amorphous silicon thin films and the application to p-channel thin film transistor  

E-Print Network [OSTI]

The material and process characteristics of boron doped hydrogenated amorphous silicon (a-Si:H) thin film deposited by plasma enhanced chemical vapor deposition technique (PECVD) have been studied. The goal is to apply the high quality films...

Nominanda, Helinda

2012-06-07T23:59:59.000Z

5

Amorphous-Silicon Thin-Film Transistors Using Chemical Vapor Deposition of Disilane  

Science Journals Connector (OSTI)

Amorphous silicon layers have been deposited by low pressure chemical vapour deposition at 450°C using disilane as the only source gas. Simple inverted staggered thin-film transistors were made with thermal silicon dioxide as the gate insulator. Field-effect mobilities for electrons and holes were 1.4 cm2/V s and 0.1 cm2/V s, respectively. In order to obtain these high mobilities the transistor structures were carefully annealed in a hydrogen-radical rich ambient.

Paul A. Breddels; Hiroshi Kanoh; Osamu Sugiura; Masakiyo Matsumura

1990-01-01T23:59:59.000Z

6

Fluorination of amorphous thin-film materials with xenon fluoride  

DOE Patents [OSTI]

A method is disclosed for producing fluorine-containing amorphous semiconductor material, preferably comprising amorphous silicon. The method includes depositing amorphous thin-film material onto a substrate while introducing xenon fluoride during the film deposition process.

Weil, R.B.

1987-05-01T23:59:59.000Z

7

Advanced polycrystalline silicon thin film solar cells using high rate plasma enhanced chemical vapour deposited amorphous silicon on textured glass.  

E-Print Network [OSTI]

??Solid phase crystallized polycrystalline silicon (poly-Si) thin-film solar cell on glass is an emerging Photovoltaics (PV) technology combining the robustness of crystalline Si material with… (more)

Jin, Guangyao

2010-01-01T23:59:59.000Z

8

E-Print Network 3.0 - amorphous-silicon-based thin-film photovoltaic...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

CELLS... . 1. Transmittance modulation spectrum TT for an amorphous silicon-based pin solar cell prepared... . ACKNOWLEDGMENTS This research has been supported through the ......

9

Low-temperature solid-phase crystallization of amorphous silicon thin films deposited by rf magnetron sputtering with substrate bias  

SciTech Connect (OSTI)

The crystallization properties of amorphous silicon (a-Si) thin film deposited by rf magnetron sputter deposition with substrate bias have been thoroughly characterized. The crystallization kinetics for films deposited with substrate bias is enhanced relative to unbiased a-Si by films. The enhanced crystallization for substrate biased a-Si films are attributed to ion enhanced nucleation of crystallites during sputter deposition which subsequently grow during the postdeposition anneal. Conversely films sputter deposited without substrate bias have more intrinsic defects and residual oxygen which enhance nucleation and retard growth, respectively, and lead to a large number of small crystallites.

Jun, Seung-Ik; Rack, Philip D.; McKnight, Timothy E.; Melechko, Anatoli V.; Simpson, Michael L. [Department of Materials Science and Engineering, The University of Tennessee, Knoxville, Tennessee 37996-2200 (United States); Molecular Scale Engineering and Nanoscale Technologies Research Group, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2006-07-10T23:59:59.000Z

10

Direct-current substrate bias effects on amorphous silicon sputter-deposited films for thin film transistor fabrication  

SciTech Connect (OSTI)

The effect that direct current (dc) substrate bias has on radio frequency-sputter-deposited amorphous silicon (a-Si) films has been investigated. The substrate bias produces a denser a-Si film with fewer defects compared to unbiased films. The reduced number of defects results in a higher resistivity because defect-mediated conduction paths are reduced. Thin film transistors (TFTs) that were completely sputter deposited were fabricated and characterized. The TFT with the biased a-Si film showed lower leakage (off-state) current, higher on/off current ratio, and higher transconductance (field effect mobility) than the TFT with the unbiased a-Si film.

Jun, Seung-Ik; Rack, Philip D.; McKnight, Timothy E.; Melechko, Anatoli V.; Simpson, Michael L. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996-2200 (United States); Molecular Scale Engineering and Nanoscale Technologies Research Group, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2005-09-26T23:59:59.000Z

11

High-Mobility Thin-Film Transistor Fabricated Using Hydrogenated Amorphous Silicon Deposited by Discharge of Disilane  

Science Journals Connector (OSTI)

Plasma-enhanced chemical vapor deposition of hydrogenated amorphous silicon (a-Si:H) film was investigated with emphasis on the effect of disilane flow rate. A coplanar thin-film transistor (TFT) was fabricated using this a-Si:H film. Silicon-hydrogen bond content in the a-Si:H film was measured by infrared absorption spectroscopy. With decrease in the disilane flow rate from 3.0 cm3/min to 1.5 cm3/min, the maximum field-effect electron mobility (µ FE) of the TFT which depends on the gate voltage increased from 3.3 cm2/( Vs) to 4.9 cm2/( Vs), accompanied by a reduction in the silicon-hydrogen bond content. There was a negative correlation between µ FE and the silicon-hydrogen bond content in the a-Si:H film. The improvement mechanism of µ FE was discussed in terms of the chemical structure of the a-Si:H film.

Shigeichi Yamamoto; Junji Nakamura; Masatoshi Migitaka

1996-01-01T23:59:59.000Z

12

Development of tandem amorphous/microcrystalline silicon thin-film large-area see-through color solar panels with reflective layer and 4-step laser scribing for building-integrated photovoltaic applications  

Science Journals Connector (OSTI)

In this work, tandem amorphous/microcrystalline silicon thin-film large-area see-through color solar modules were successfully designed and developed for building-integrated photovoltaic applications. Novel and key technologies of reflective layers and ...

Chin-Yi Tsai, Chin-Yao Tsai

2014-01-01T23:59:59.000Z

13

Metal-induced nanocrystalline structures in Ni-containing amorphous silicon thin films  

SciTech Connect (OSTI)

The mechanisms of silicon nanocrystal structure formation in amorphous Si films have been studied for a relative Ni impurity content varying between 0.1 and 10 at. %, i.e., from a Ni doping range to the Si-Ni alloy phase. The films, deposited by the cosputtering technique at 200 deg. C, were submitted to isochronal (15 min) annealing cycles up to 800 deg. C. Four different substrates were used to deposit the studied films: crystalline (c-) quartz, c-Si, c-Ge, and glass. Both the two orders of magnitude impurity concentration range variation and the very short annealing times were selected on purpose to investigate the first steps of the mechanism leading to the appearance of crystal seeds. The conclusions of this work are the following: (a) Ni impurity induces the low-temperature crystallization of amorphous silicon; (b) the NiSi{sub 2} silicide phase mediates, at the surface or in the bulk of the film, the crystallization process; and (c) the onset of crystallization and the crystalline fraction of the samples at each temperature depend not only on the Ni impurity concentration, but also on the nature of the substrate.

Ferri, F. A.; Zanatta, A. R.; Chambouleyron, I. [Instituto de Fisica de Sao Carlos-USP, Sao Carlos 13560-250, Sao Paulo (Brazil); Instituto de Fisica Gleb Wataghin-UNICAMP, Campinas 13083-970, Sao Paulo (Brazil)

2006-11-01T23:59:59.000Z

14

Research on high-efficiency, single-junction, monolithic, thin-film amorphous silicon solar cells: Annual subcontract report, May 1985 - Jul 1986  

SciTech Connect (OSTI)

A study was undertaken of the optoelectronic properties of amorphous silicon-hydrogen thin films deposited from disilane at high deposition rates. The information derived from this study was used to fabricate amorphous silicon solar cells with efficiencies exceeding 7%. The intrinsic layer of these solar cells was deposited at 15 angstroms/second. Material properties investigated included dark conductivity, photoconductivity, minority carrier diffusion length, and density of states. The solar cells properties characterized were absolute quantum yield and simulated global AM 1.5 efficiencies. Investigations were undertaken utilizing optical and infrared spectroscopy to optimize the microstructures of the intrinsic amorphous silicon. That work was sponsored by the New York State Energy Research and Development Authority. The information was used to optimize the intrinsic layer of amorphous silicon solar cells, resulting in AM 1.5 efficiencies exceeding 7%.

Wiesmann, H.; Dolan, J.; Fricano, G.; Danginis, V.

1987-02-01T23:59:59.000Z

15

Impact of solid-phase crystallization of amorphous silicon on the chemical structure of the buried Si/ZnO thin film solar cell interface  

SciTech Connect (OSTI)

The chemical interface structure between phosphorus-doped hydrogenated amorphous silicon and aluminum-doped zinc oxide thin films is investigated with soft x-ray emission spectroscopy (XES) before and after solid-phase crystallization (SPC) at 600C. In addition to the expected SPC-induced phase transition from amorphous to polycrystalline silicon, our XES data indicates a pronounced chemical interaction at the buried Si/ZnO interface. In particular, we find an SPC-enhanced formation of Si-O bonds and the accumulation of Zn in close proximity to the interface. For an assumed closed and homogeneous SiO2 interlayer, an effective thickness of (5+2)nm after SPC could be estimated.

Bar, M.; Wimmer, M.; Wilks, R. G.; Roczen, M.; Gerlach, D.; Ruske, F.; Lips, K.; Rech, B.; Weinhardt, L.; Blum, M.; Pookpanratana, S.; Krause, S.; Zhang, Y.; Heske, C.; Yang, W.; Denlinger, J. D.

2010-04-30T23:59:59.000Z

16

Amorphous hafnium-indium-zinc oxide semiconductor thin film transistors  

Science Journals Connector (OSTI)

We reported on the performance and electrical properties of co-sputtering-processed amorphous hafnium-indium-zinc oxide (?-HfIZO) thin film transistors (TFTs). Co-sputtering-processed ?-HfIZO thin films have shown an amorphous phase in nature. ...

Sheng-Po Chang; San-Syong Shih

2012-01-01T23:59:59.000Z

17

Polycrystalline silicon thin-film solar cells on glass by ion-assisted deposition.  

E-Print Network [OSTI]

??Polycrystalline silicon (pc-Si, grain size > 1??m, no amorphous tissue) on glass is an interesting material for thin-film solar cells due to the low costs,… (more)

Straub, Axel

2005-01-01T23:59:59.000Z

18

Nanostructured silicon thin films deposited by PECVD in the presence of silicon nanoparticles  

SciTech Connect (OSTI)

Nanostructured silicon thin films have been deposited by plasma enhanced chemical vapor deposition at low substrate temperature (100 C) in the presence of silicon nanoparticles. The nanostructure of the films was revealed by transmission electron microscopy, Raman spectroscopy and X-ray diffraction, which showed ordered silicon domains (1--2 nm) embedded in an amorphous silicon matrix. These ordered domains are due to the particles created in the discharge that contribute to the film growth. One consequence of the incorporation of nanoparticles is the accelerated crystallization of the nanostructured silicon thin films when compared to standard a-Si:H, as shown by the electrical characterization during the annealing.

Viera, G.; Cabarrocas, P.R.; Hamma, S.; Sharma, S.N.; Costa, J.; Bertran, E.

1997-07-01T23:59:59.000Z

19

Multi-resonant silver nano-disk patterned thin film hydrogenated amorphous silicon solar cells for Staebler-Wronski effect compensation  

E-Print Network [OSTI]

We study polarization independent improved light trapping in commercial thin film hydrogenated amorphous silicon (a-Si:H) solar photovoltaic cells using a three-dimensional silver array of multi-resonant nano-disk structures embedded in a silicon nitride anti-reflection coating (ARC) to enhance optical absorption in the intrinsic layer (i-a-Si:H) for the visible spectrum for any polarization angle. Predicted total optical enhancement (OE) in absorption in the i-a-Si:H for AM-1.5 solar spectrum is 18.51% as compared to the reference, and producing a 19.65% improvement in short-circuit current density (JSC) over 11.7 mA/cm2 for a reference cell. The JSC in the nano-disk patterned solar cell (NDPSC) was found to be higher than the commercial reference structure for any incident angle. The NDPSC has a multi-resonant optical response for the visible spectrum and the associated mechanism for OE in i-a-Si:H layer is excitation of Fabry-Perot resonance facilitated by surface plasmon resonances. The detrimental Staebl...

Vora, Ankit; Pearce, Joshua M; Bergstrom, Paul L; Güney, Durdu Ö

2014-01-01T23:59:59.000Z

20

NANO-INDENTATION OF COPPER THIN FILMS ON SILICON SUBSTRATES  

E-Print Network [OSTI]

NANO-INDENTATION OF COPPER THIN FILMS ON SILICON SUBSTRATES S. Suresh1 , T.-G. Nieh2 and B.W. Choi2: Mechanical properties; Nano-indentation; Thin films; Copper; Dislocations Introduction Indentation methods films on substrates (e.g., [2,3]) using instrumented indentation. Nano-indentation studies of thin films

Suresh, Subra

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Efficient light trapping structure in thin film silicon solar cells  

E-Print Network [OSTI]

Thin film silicon solar cells are believed to be promising candidates for continuing cost reduction in photovoltaic panels because silicon usage could be greatly reduced. Since silicon is an indirect bandgap semiconductor, ...

Sheng, Xing

22

Microstructure and properties of copper thin films on silicon substrates  

E-Print Network [OSTI]

copper thin films but on an expense of conductivity. This study proposes a technique to deposit high strength and high conductivity copper thin films on different silicon substrates at room temperature. Single crystal Cu (100) and Cu (111) have been grown...

Jain, Vibhor Vinodkumar

2009-05-15T23:59:59.000Z

23

The silicon/zinc oxide interface in amorphous silicon-based thin-film solar cells: Understanding an empirically optimized contact  

SciTech Connect (OSTI)

The electronic structure of the interface between the boron-doped oxygenated amorphous silicon 'window layer' (a-SiO{sub x}:H(B)) and aluminum-doped zinc oxide (ZnO:Al) was investigated using hard x-ray photoelectron spectroscopy and compared to that of the boron-doped microcrystalline silicon ({mu}c-Si:H(B))/ZnO:Al interface. The corresponding valence band offsets have been determined to be (-2.87 {+-} 0.27) eV and (-3.37 {+-} 0.27) eV, respectively. A lower tunnel junction barrier height at the {mu}c-Si:H(B)/ZnO:Al interface compared to that at the a-SiO{sub x}:H(B)/ZnO:Al interface is found and linked to the higher device performances in cells where a {mu}c-Si:H(B) buffer between the a-Si:H p-i-n absorber stack and the ZnO:Al contact is employed.

Gerlach, D.; Wilks, R. G.; Wimmer, M.; Felix, R.; Gorgoi, M.; Lips, K.; Rech, B. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Wippler, D.; Mueck, A.; Meier, M.; Huepkes, J. [Institut fuer Energie- und Klimaforschung, Forschungszentrum Juelich GmbH, Wilhelm-Johnen-Strasse, D-52428 Juelich (Germany); Lozac'h, M.; Ueda, S.; Sumiya, M. [National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Yoshikawa, H. [Synchrotron X-ray Station at SPring-8, NIMS, Kouto 1-1-1, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Kobayashi, K. [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Kouto 1-1-1, SPring-8, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan); Baer, M. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Institut fuer Physik und Chemie, Brandenburgische Technische Universitaet Cottbus, Konrad-Wachsmann-Allee 1, D-03046 Cottbus (Germany)

2013-07-08T23:59:59.000Z

24

A Review of Thin Film Silicon for Solar Cell Applications  

E-Print Network [OSTI]

A Review of Thin Film Silicon for Solar Cell Applications May 99 Contents 1 Introduction 3 2 Low 2.2.3 Deposition onto foreign substrates with the intention of improving crystallographic nature Field Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 11

25

Boron- and phosphorus-doped polycrystalline silicon thin films prepared by silver-induced layer exchange  

SciTech Connect (OSTI)

Intentional boron and phosphorus doping of polycrystalline silicon thin films on glass prepared by the silver-induced layer exchange is presented. A silver/(titanium) oxide/amorphous silicon stack is annealed at temperatures below the eutectic temperature of the Ag/Si system, leading to a complete layer exchange and simultaneous crystallization of the amorphous silicon. Intentional doping of the amorphous silicon prior to the exchange process results in boron- or phosphorus-doped polycrystalline silicon. Hall effect measurements show carrier concentrations between 2 Multiplication-Sign 10{sup 17} cm{sup -3} and 3 Multiplication-Sign 10{sup 20} cm{sup -3} for phosphorus and 4 Multiplication-Sign 10{sup 18} cm{sup -3} to 3 Multiplication-Sign 10{sup 19} cm{sup -3} for boron-doped layers, with carrier mobilities up to 90 cm{sup 2}/V s.

Antesberger, T.; Wassner, T. A.; Jaeger, C.; Algasinger, M.; Kashani, M.; Scholz, M.; Matich, S.; Stutzmann, M. [Walter Schottky Institut and Physics Department, Technische Universitaet Muenchen, Am Coulombwall 4, 85748 Garching (Germany)] [Walter Schottky Institut and Physics Department, Technische Universitaet Muenchen, Am Coulombwall 4, 85748 Garching (Germany)

2013-05-27T23:59:59.000Z

26

Amorphous Silicon  

Broader source: Energy.gov [DOE]

DOE has a proven track record of funding successes in amorphous silicon (a-Si)research. A list of current projects, summary of the benefits, and discussion on the production and manufacturing of...

27

Design of plasmonic back structures for efficiency enhancement of thin-film amorphous Si solar cells  

Science Journals Connector (OSTI)

Metallic back structures with one-dimensional periodic nanoridges attached to a thin-film amorphous Si (a-Si) solar cell are numerically studied. At the interfaces between a-Si and...

Bai, Wenli; Gan, Qiaoqiang; Bartoli, Filbert; Zhang, Jing; Cai, Likang; Huang, Yidong; Song, Guofeng

2009-01-01T23:59:59.000Z

28

NREL: Energy Analysis - Crystalline Silicon and Thin Film Photovoltaic  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Crystalline Silicon and Thin Film Photovoltaic Results - Life Cycle Crystalline Silicon and Thin Film Photovoltaic Results - Life Cycle Assessment Harmonization Life Cycle Greenhouse Gas Emissions from Solar Photovoltaics (Fact Sheet) Cover of the Life Cycle Greenhouse Gas Emissions from Solar Photovoltaics factsheet Download the Fact Sheet Over the last 30 years, hundreds of life cycle assessments (LCAs) have been conducted and published for a variety of residential and utility-scale solar photovoltaic (PV) systems with wide-ranging results. The inconsistencies in these results can be attributed to the technologies evaluated-such as differing system designs, real-world versus conceptual systems, or technology improvements over time-and life cycle assessment methods and assumptions. To better understand greenhouse gas (GHG) emissions from commercial

29

Highly conductive p-type microcrystalline silicon thin films  

SciTech Connect (OSTI)

In the development of thin film solar cells there is presently an increasing interest in microcrystalline silicon, deposited at low temperatures (200--400 C). The plasma deposition of boron doped microcrystalline films was optimized with respect to crystallinity and doping efficiency. High room temperature conductivities up to 39 Scm{sup {minus}1} were achieved under condition when the energy of positive ions impinging on the growth surface is minimized.

Heintze, M.; Schmitt, M. [Univ. Stuttgart (Germany). Inst. fuer Physikalische Elektronik

1996-12-31T23:59:59.000Z

30

Formation of thin-film resistors on silicon substrates  

DOE Patents [OSTI]

The formation of thin-film resistors by the ion implantation of a metallic conductive layer in the surface of a layer of phosphosilicate glass or borophosphosilicate glass which is deposited on a silicon substrate. The metallic conductive layer materials comprise one of the group consisting of tantalum, ruthenium, rhodium, platinum and chromium silicide. The resistor is formed and annealed prior to deposition of metal, e.g. aluminum, on the substrate.

Schnable, George L. (Montgomery County, PA); Wu, Chung P. (Hamilton Township, Mercer County, NJ)

1988-11-01T23:59:59.000Z

31

The origin of white luminescence from silicon oxycarbide thin films  

SciTech Connect (OSTI)

Silicon oxycarbide (SiC{sub x}O{sub y}) is a promising material for achieving strong room-temperature white luminescence. The present work investigated the mechanisms for light emission in the visible/ultraviolet range (1.5–4.0?eV) from chemical vapor deposited amorphous SiC{sub x}O{sub y} thin films, using a combination of optical characterizations and electron paramagnetic resonance (EPR) measurements. Photoluminescence (PL) and EPR studies of samples, with and without post-deposition passivation in an oxygen and forming gas (H{sub 2} 5 at.?% and N{sub 2} 95 at.?%) ambient, ruled out typical structural defects in oxides, e.g., Si-related neutral oxygen vacancies or non-bridging oxygen hole centers, as the dominant mechanism for white luminescence from SiC{sub x}O{sub y}. The observed intense white luminescence (red, green, and blue emission) is believed to arise from the generation of photo-carriers by optical absorption through C-Si-O related electronic transitions, and the recombination of such carriers between bands and/or at band tail states. This assertion is based on the realization that the PL intensity dramatically increased at an excitation energy coinciding with the E{sub 04} band gaps of the material, as well as by the observed correlation between the Si-O-C bond density and the PL intensity. An additional mechanism for the existence of a blue component of the white emission is also discussed.

Nikas, V.; Gallis, S., E-mail: sgalis@us.ibm.com; Huang, M.; Kaloyeros, A. E. [College of Nanoscale Sciences and Engineering, State University of New York, Albany, New York 12203 (United States); Nguyen, A. P. D.; Stesmans, A.; Afanas'ev, V. V. [Department of Physics and Astronomy, University of Leuven, Celestijnenlaan 200D, B-3001 Leuven (Belgium)

2014-02-10T23:59:59.000Z

32

Research on high-efficiency, single-junction, monolithic, thin-film amorphous silicon solar cells: Phase II annual subcontract report, 1 January 1985--31 January 1986  

SciTech Connect (OSTI)

This report presents results of the second phase of research on high-efficiency, single-junction, monolithic, thin-film a-Si solar cells. Five glow-discharge deposition systems, including a new in-line, multichamber system, were used to grow both doped and undoped a-Si:H. A large number of silane and disilane gas cylinders were analyzed with a gas chromatography/mass spectroscopy system. Strong correlations were found between the breakdown voltage, the deposition rate, the diffusion length, and the conversion efficiency for varying cathode-anode separations in a DC glow-discharge deposition mode. Tin oxide films were grown by chemical vapor deposition with either tetramethyl tin (TMT) or tin tetrachloride (TTC). The best were grown with TMT, but TTC films had a more controlled texture for light trapping and provided a better contact to the p-layer. The best results were obtained with 7059 glass substrates. Efficiencies as high as 10.86% were obtained in p-i-n cells with superlattice p-layers and as high as 10.74% in cells with both superlattice p- and n-layers. Measurements showed that the boron-doping level in the p-layer can strongly affect transport in the i-layer, which can be minimized by reactive flushing before i-layer deposition. Stability of a-Si:H cells is improved by light doping. 51 refs., 64 figs., 21 tabs.

Carlson, D.E.; Ayra, R.R.; Bennett, M.S.; Catalano, A.; D'Aiello, R.V.; Dickson, C.R.; McVeigh, J.; Newton, J.; O'Dowd, J.; Oswald, R.S.; Rajan, K.

1988-09-01T23:59:59.000Z

33

Advanced Light-Trapping in Thin-Film Silicon Solar Cells  

Science Journals Connector (OSTI)

Light-trapping schemes are essential for high efficiency thin-film Silicon devices. Implementation of various light-trapping/scattering elements will be discussed. An optimum textured...

Wyrsch, Nicolas

34

Design, fabrication and optical characterization of photonic crystal assisted thin film monocrystalline-silicon solar cells  

Science Journals Connector (OSTI)

In this paper, we present the integration of an absorbing photonic crystal within a monocrystalline silicon thin film photovoltaic stack fabricated without epitaxy. Finite difference...

Meng, Xianqin; Depauw, Valérie; Gomard, Guillaume; El Daif, Ounsi; Trompoukis, Christos; Drouard, Emmanuel; Jamois, Cécile; Fave, Alain; Dross, Frédéric; Gordon, Ivan; Seassal, Christian

2012-01-01T23:59:59.000Z

35

Quasi-Reversible Oxygen Exchange of Amorphous IGZO Thin Films  

E-Print Network [OSTI]

Center In situ electrical properties of a-IGZO thin films were carried out at 200ºC as a function of carrier content vs. pO2) analysis should be applicable for studying the underlying carrier generation

Shahriar, Selim

36

Spectroscopic ellipsometry characterization of thin-film silicon nitride  

SciTech Connect (OSTI)

We have measured and analyzed the optical characteristics of a series of silicon nitride thin films prepared by plasma-enhanced chemical vapor deposition on silicon substrates for photovoltaic applications. Spectroscopic ellipsometry measurements were made by using a two-channel spectroscopic polarization modulator ellipsometer that measures N, S, and C data simultaneously. The data were fit to a model consisting of air / roughness / SiN / crystalline silicon. The roughness was modeled using the Bruggeman effective medium approximation, assuming 50% SiN, 50% voids. The optical functions of the SiN film were parameterized using a model by Jellison and Modine. All the {Chi}{sup 2} are near 1, demonstrating that this model works extremely well for all SiN films. The measured dielectric functions were used to make optimized SiN antireflection coatings for crystalline silicon solar cells.

Jellison, G.E. Jr.; Modine, F.A. [Oak Ridge National Lab., TN (United States); Doshi, P.; Rohatgi, A. [Georiga Inst. of Technology, Atlanta, GA (United States)

1997-05-01T23:59:59.000Z

37

Amorphous semiconducting and conducting transparent metal oxide thin films and production thereof  

DOE Patents [OSTI]

Metal oxide thin films and production thereof are disclosed. An exemplary method of producing a metal oxide thin film may comprise introducing at least two metallic elements and oxygen into a process chamber to form a metal oxide. The method may also comprise depositing the metal oxide on a substrate in the process chamber. The method may also comprise simultaneously controlling a ratio of the at least two metallic elements and a stoichiometry of the oxygen during deposition. Exemplary amorphous metal oxide thin films produced according to the methods herein may exhibit highly transparent properties, highly conductive properties, and/or other opto-electronic properties.

Perkins, John (Boulder, CO); Van Hest, Marinus Franciscus Antonius Maria (Lakewood, CO); Ginley, David (Evergreen, CO); Taylor, Matthew (Golden, CO); Neuman, George A. (Holland, MI); Luten, Henry A. (Holland, MI); Forgette, Jeffrey A. (Hudsonville, MI); Anderson, John S. (Holland, MI)

2010-07-13T23:59:59.000Z

38

Atomic hydrogen interactions with amorphous carbon thin films Bhavin N. Jariwala,1  

E-Print Network [OSTI]

Atomic hydrogen interactions with amorphous carbon thin films Bhavin N. Jariwala,1 Cristian V-scale interactions of H atoms with hydrogenated amorphous carbon a-C:H films were identified using molecular dynamics through a detailed analysis of the MD trajectories. The MD simulations showed that hydrogenation occurs

Ciobanu, Cristian

39

Extended light scattering model incorporating coherence for thin-film silicon solar cells  

E-Print Network [OSTI]

Extended light scattering model incorporating coherence for thin-film silicon solar cells Thomas film solar cells. The model integrates coherent light propagation in thin layers with a direct, non potential for light trapping in textured thin film silicon solar cells. VC 2011 American Institute

Lenstra, Arjen K.

40

Comparison of Ag and SiO2 Nanoparticles for Light Trapping Applications in Silicon Thin Film Solar Cells  

Science Journals Connector (OSTI)

Comparison of Ag and SiO2 Nanoparticles for Light Trapping Applications in Silicon Thin Film Solar Cells ... † Department

Martin Theuring; Peng Hui Wang; Martin Vehse; Volker Steenhoff; Karsten von Maydell; Carsten Agert; Alexandre G. Brolo

2014-09-10T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Thermal Conductivity of Ordered Mesoporous Nanocrystalline Silicon Thin Films Made from Magnesium Reduction of Polymer-  

E-Print Network [OSTI]

Thermal Conductivity of Ordered Mesoporous Nanocrystalline Silicon Thin Films Made from Magnesium-assembly of mesoporous silica followed by magnesium reduction. The periodic ordering of pores in mesoporous silicon

Pilon, Laurent

42

May 2003 NREL/CP-520-33933 Amorphous and Thin-Film  

E-Print Network [OSTI]

Roedern, J. Yang, P. Sims, X. Deng, V. Dalal, D. Carlson, and T. Wang Presented at the National and Thin-Film Silicon Brent P. Nelson,1 Harry A. Atwater,2 Bolko von Roedern,1 Jeff Yang,3 Paul Sims,4. (c) "Thin Silicon-on-Ceramic Solar Cells" by Paul Sims. (d

Deng, Xunming

43

Silicon Thin-Film Formation by Direct Photochemical Decomposition of Disilane  

Science Journals Connector (OSTI)

Silicon thin-films have been deposited by the direct photolysis of disilane at a substrate temperature below 300°C. The growth rate depends on irradiation intensity of a low pressure mercury-lamp, and a typical rate of 15 Å/min has been obtained under ~0.08 watts/cm2 illumination, regardless of substrate temperature. The deposited films are composed of an amorphous network containing bonded-hydrogen in the range 6–9 at.%. The bonding configurations of SiH groups varied from silicon dihydride to monohydride with increasing substrate temperature, and correspondingly the dark conductivity decreased from 10-7 to 10-11 ?-1cm-1. A broad photoluminescence peak at 1.4 eV was observed for a specimen grown at 200°C.

Yasuyoshi Mishima; Masataka Hirose; Yukio Osaka; Kunihiro Nagamine; Yoshinori Ashida; Nobuhisa Kitagawa; Kazuyoshi Isogaya

1983-01-01T23:59:59.000Z

44

Light harvesting by planar photonic crystal in solar cells: The case of amorphous silicon  

E-Print Network [OSTI]

Light harvesting by planar photonic crystal in solar cells: The case of amorphous silicon Guillaume on light management in silicon thin film solar cells, using photonic crystals (PhC) structures. We by means of optical simulations performed on realistic thin film solar cell stacks. Theoretically

Boyer, Edmond

45

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

DOE Patents [OSTI]

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

McKee, Rodney A. (Kingston, TN); Walker, Frederick Joseph (Oak Ridge, TN)

2000-01-01T23:59:59.000Z

46

Amorphous and microcrystalline silicon technology--1997. Materials Research Society symposium proceedings, Volume 467  

SciTech Connect (OSTI)

This book was divided into the following parts: Staebler-Wronski and Fundamental Defect Studies in Amorphous Silicon; The Story of Hydrogen in Amorphous Silicon; Photoelectric Properties of Amorphous Silicon; Deposition and Properties of Microcrystalline Silicon; Deposition Studies for Amorphous Silicon and Related Materials; Solar Cells; Thin-Film Transistors; and Sensors and Novel Device Concepts. Separate abstracts were prepared for most of the papers in the volume.

Wagner, S.; Hack, M.; Schiff, E.A.; Schropp, R.; Shimizu, I. [eds.

1997-07-01T23:59:59.000Z

47

Electronic Structure and Chemical Bonding of Amorphous Chromium Carbide Thin Films  

E-Print Network [OSTI]

The microstructure, electronic structure, and chemical bonding of chromium carbide thin films with different carbon contents have been investigated with high-resolution transmission electron microscopy, electron energy loss spectroscopy and soft x-ray absorption-emission spectroscopies. Most of the films can be described as amorphous nanocomposites with non-crystalline CrCx in an amorphous carbon matrix. At high carbon contents, graphene-like structures are formed in the amorphous carbon matrix. At 47 at% carbon content, randomly oriented nanocrystallites are formed creating a complex microstructure of three components. The soft x-ray absorption-emission study shows additional peak structures exhibiting non-octahedral coordination and bonding.

Magnuson, Martin; Lu, Jun; Hultman, Lars; Jansson, Ulf; 10.1088/0953-8984/24/22/225004

2012-01-01T23:59:59.000Z

48

Remarkable progress in thin-film silicon solar cells using high-efficiency triple-junction technology  

Science Journals Connector (OSTI)

Abstract Despite the many advantages of thin-film silicon (Si) solar cells, their low efficiencies remain a challenge that must be overcome. Efficient light utilization across the solar spectrum is required to achieve efficiencies over 15%, allowing them to be competitive with other solar cell technologies. To produce high-efficiency thin-film Si solar cells, we have developed triple-junction solar cell structures to enhance solar spectrum utilization. To maximize the light management, in-house ZnO:Al layers with high haze ratios and high transmittances were developed. In addition, novel doping layers, such as n-type microcrystalline silicon oxide (µc-SiOx:H), which has a very low refractive index, and p-type microcrystalline silicon oxide (µc-SiOx:H), which has a wide bandgap, were successfully applied to the optical reflector and the window layer, respectively. Thin-film quality control techniques for the deposition of hydrogenated amorphous silicon (a-Si:H) in the top cell, hydrogenated amorphous silicon-germanium (a-SiGe:H) or hydrogenated microcrystalline silicon (?c-Si:H) in the middle cell, and hydrogenated microcrystalline silicon (?c-Si:H) in the bottom cell were also important factors leading to the production of high-efficiency triple-junction solar cells. As a result of this work, an initial efficiency of 16.1% (in-house measurement) in the a-Si:H/a-SiGe:H/?c-Si:H stack and a stabilized efficiency of 13.4% (confirmed by NREL) in the a-Si:H/?c-Si:H/?c-Si:H stack were successfully achieved in a small-area triple-junction solar cell with dimensions of 1 cm×1 cm.

Soohyun Kim; Jin-Won Chung; Hyun Lee; Jinhee Park; Younho Heo; Heon-Min Lee

2013-01-01T23:59:59.000Z

49

Interactions between radical growth precursors on plasma-deposited silicon thin-film surfaces  

SciTech Connect (OSTI)

We present a detailed analysis of the interactions between growth precursors, SiH{sub 3} radicals, on surfaces of silicon thin films. The analysis is based on a synergistic combination of density functional theory calculations on the hydrogen-terminated Si(001)-(2x1) surface and molecular-dynamics (MD) simulations of film growth on surfaces of MD-generated hydrogenated amorphous silicon (a-Si:H) thin films. In particular, the authors find that two interacting growth precursors may either form disilane (Si{sub 2}H{sub 6}) and desorb from the surface, or disproportionate, resulting in the formation of a surface dihydride (adsorbed SiH{sub 2} species) and gas-phase silane (SiH{sub 4}). The reaction barrier for disilane formation is found to be strongly dependent on the local chemical environment on the silicon surface and reduces (or vanishes) if one/both of the interacting precursors is/are in a ''fast diffusing state,'' i.e., attached to fivefold coordinated surface Si atoms. Finally, activation energy barriers in excess of 1 eV are obtained for two chemisorbed (i.e., bonded to a fourfold coordinated surface Si atom) SiH{sub 3} radicals. Activation energy barriers for disproportionation follow the same tendency, though, in most cases, higher barriers are obtained compared to disilane formation reactions starting from the same initial configuration. MD simulations confirm that disilane formation and disproportionation reactions also occur on a-Si:H growth surfaces, preferentially in configurations where at least one of the SiH{sub 3} radicals is in a ''diffusive state.'' Our results are in agreement with experimental observations and results of plasma process simulators showing that the primary source for disilane in low-power plasmas may be the substrate surface.

Bakos, Tamas; Valipa, Mayur S.; Maroudas, Dimitrios [Department of Chemical Engineering, University of Massachusetts, Amherst, Massachusetts 01003-3110 (United States)

2007-03-21T23:59:59.000Z

50

Formation and post-deposition compression of smooth and processable silicon thin films from nanoparticle suspensions  

E-Print Network [OSTI]

nanoparticle suspensions Noah T. Jafferisa) and James C. Sturm Department of Electrical Engineering, Princeton and processable silicon thin-films from single-crystal silicon-nanoparticle suspensions. Single-crystal Si-nanoparticles on printing silicon from nanoparticles has shown much promise.3,4 Ha¨rting et al.4 report screen-printed films

51

Hydrogenated amorphous silicon films prepared by glow discharge of disilane  

SciTech Connect (OSTI)

This report describes the results of an investigation of the properties of hydrogenated amorphous silicon films and the efficiency of amorphous silicon solar cells deposited from disilane at rates of 1.5 nanometers/second or greater. The study was divided into two parts, investigation of basic materials properties of hydrogenated amorphous silicon thin films and the fabrication of glass-P-I-N-metal solar cells. The thin film materials properties investigated included the dark conductivity, photoconductivity, dihydride/monohydride concentration ratio, activation energy, and mobility-lifetime product. Hydrogenated amorphous silicon solar cells were fabricated with an intrinsic layer which was deposited at 1.5 nanometers/second. The absolute and reverse bias quantum yields were measured and solar cell efficiencies of 5% were achieved. Attempts to increase the efficiency by reverse bias annealing are also reported. 7 refs., 27 figs.

Wiesmann, H.J. (UHT Corp., Dobbs Ferry, NY (USA))

1990-01-01T23:59:59.000Z

52

Mechanics of thin-film transistors and solar cells on flexible substrates Helena Gleskova*  

E-Print Network [OSTI]

1 Mechanics of thin-film transistors and solar cells on flexible substrates Helena Gleskova* , I be minimized throughout the fabrication process. Amorphous silicon thin-film transistors and solar cells, thin-film transistor, solar cell, flexible electronics Phone: (609) 258-4626, Fax: (609) 258-3585, E

53

Plasmonic enhancement of thin-film solar cells using gold-black C.J. Fredricksena  

E-Print Network [OSTI]

Plasmonic enhancement of thin-film solar cells using gold-black coatings C.J. Fredricksena , D. R thin-film amorphous-silicon solar cells enhance the short-circuit current by 20% over a broad spectrum and locally enhance the field strength. Keywords: plasmonics, thin-film, solar cell, metallic nanoparticles

Peale, Robert E.

54

Amorphous and microcrystalline silicon technology -- 1998  

SciTech Connect (OSTI)

Although this new volume from MRS is the 16th in a long-standing and successful series, the focus is no longer limited to hydrogenated amorphous silicon (a-Si:H). The distinction between short- and medium-range order, and between homogeneous and heterogeneous semiconductor materials, is indeed too difficult to maintain. Instead, the volume covers amorphous and microcrystalline silicon from materials physics to new applications. Papers from a joint session with a symposium on ``Flat-Panel Display Materials and Large-Area Processes`` are included. The volume also features special focused sessions on heterogeneous materials, color sensors and radiation imaging, and parameter extraction and device modeling. Topics include: amorphous and polycrystalline thin-film transistors; solar cells; color and X-ray sensors, novel devices, luminescence and sensitization; device modeling and parameter extraction; growth, alloys and clathrates; metastability, hydrogen, atomic and electronic structure; defects and charge transport; and heterogeneous silicon--formation, properties and devices. It includes 152 papers.

Schropp, R. [ed.] [Utrecht Univ. (Netherlands); Branz, H.M. [ed.] [National Renewable Energy Lab., Golden, CO (United States); Shimizu, Isamu [ed.] [Tokyo Inst. of Tech. (Japan); Wagner, S. [ed.] [Princeton Univ., NJ (United States); Hack, M. [ed.

1999-08-01T23:59:59.000Z

55

Tritium in amorphous silicon  

SciTech Connect (OSTI)

Preliminary results on infrared and luminescence measurements of tritium incorporated amorphous silicon are reported. Tritium is an unstable isotope that readily substitutes hydrogen in the amorphous silicon network. Due to its greater mass, bonded tritium is found to introduce new stretching modes in the infrared spectrum. Inelastic collisions between the beta particles, produced as a result of tritium decay, and the amorphous silicon network, results in the generation of excess electron-hole pairs. Radiative recombination of these carriers is observed.

Sidhu, L.S.; Kosteski, T.; O`Leary, S.K.; Gaspari, F.; Zukotynski, S. [Univ. of Toronto, Ontario (Canada). Dept. of Electrical and Computer Engineering; Kherani, N.P.; Shmadya, W. [Ontario Hydro Technologies, Toronto, Ontario (Canada)

1996-12-31T23:59:59.000Z

56

Metal Nanoparticles Enhanced Optical Absorption in Thin Film Solar Cells  

Science Journals Connector (OSTI)

The plasmonic enhanced absorption for thin film solar cells with silver nanoparticles (NPs) deposited on top of the amorphous silicon film (a-Si:H) solar cells and embedded inside the...

Xie, Wanlu; Liu, Fang; Qu, Di; Xu, Qi; Huang, Yidong

57

Bendable single crystal silicon thin film transistors formed by printing on plastic substrates  

E-Print Network [OSTI]

Bendable single crystal silicon thin film transistors formed by printing on plastic substrates E on plastic substrates using an efficient dry transfer printing technique. In these devices, free standing-Si is then transferred, to a specific location and with a controlled orientation, onto a thin plastic sheet

Rogers, John A.

58

Highly Ordered Vertical Silicon Nanowire Array Composite Thin Films for Thermoelectric Devices  

E-Print Network [OSTI]

Highly Ordered Vertical Silicon Nanowire Array Composite Thin Films for Thermoelectric Devices for thermoelectric devices are presented. Inter- ference lithography was used to pattern square lattice photoresist. The Si NW arrays were embedded in SOG to form a dense and robust composite material for device

Bowers, John

59

Growth-front roughening in amorphous silicon films by sputtering T. Karabacak,* Y.-P. Zhao, G.-C. Wang, and T.-M. Lu  

E-Print Network [OSTI]

Growth-front roughening in amorphous silicon films by sputtering T. Karabacak,* Y.-P. Zhao, G industry and is a material of special interest. The dy- namic roughening of silicon thin films grown

Wang, Gwo-Ching

60

CRYSTALLINE SILICON THIN-FILM SOLAR CELLS FROM THE POROUS SILICON PROCESS APPLYING CONVECTION ASSISTED CHEMICAL VAPOR DEPOSITION  

E-Print Network [OSTI]

CRYSTALLINE SILICON THIN-FILM SOLAR CELLS FROM THE POROUS SILICON PROCESS APPLYING CONVECTION ASSISTED CHEMICAL VAPOR DEPOSITION Barbara Terheiden,1* Thomas Kunz,2 Ingo Burkert2 , Renate Horbelt,1, D-91058 Erlangen, Germany ABSTRACT: Convection assisted chemical vapor deposition (CoCVD) is applied

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Universality of non-Ohmic shunt leakage in thin-film solar cells S. Dongaonkar,1,a  

E-Print Network [OSTI]

Universality of non-Ohmic shunt leakage in thin-film solar cells S. Dongaonkar,1,a J. D. Servaites thin-film solar cell types: hydrogenated amorphous silicon a-Si:H p-i-n cells, organic bulk understanding of thin film solar cell device physics, including important module performance variability issues

Alam, Muhammad A.

62

Silicon Nanoparticle Synthesis and Modeling for Thin Film Solar Cells.  

E-Print Network [OSTI]

??Nanometer-scale silicon shows extraordinary electronic and optical properties that are not available for bulk silicon, and many investigations toward applications in optoelectronic devices are being… (more)

Albu, Zahra

2014-01-01T23:59:59.000Z

63

In situ measurements of stress evolution in silicon thin films during  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

In situ measurements of stress evolution in silicon thin films during In situ measurements of stress evolution in silicon thin films during electrochemical lithiation and delithiation Title In situ measurements of stress evolution in silicon thin films during electrochemical lithiation and delithiation Publication Type Journal Article Year of Publication 2010 Authors Sethuraman, Vijay A., Michael J. Chon, Maxwell Shimshak, Venkat Srinivasan, and Pradeep R. Guduru Journal Journal of Power Sources Volume 195 Start Page 5062 Issue 15 Pagination 5062-5066 Date Published 08/2010 Keywords In situ stress measurement, Lithium-ion battery, Mechanical dissipation, Multi-beam optical sensor (MOS), Open-circuit relaxation, Silicon anode Abstract We report in situ measurements of stress evolution in a silicon thin-film electrode during electrochemical lithiation and delithiation by using the multi-beam optical sensor (MOS) technique. Upon lithiation, due to substrate constraint, the silicon electrode initially undergoes elastic deformation, resulting in rapid rise of compressive stress. The electrode begins to deform plastically at a compressive stress of ca. -1.75 GPa; subsequent lithiation results in continued plastic strain, dissipating mechanical energy. Upon delithiation, the electrode first undergoes elastic straining in the opposite direction, leading to a tensile stress of ca. 1 GPa; subsequently, it deforms plastically during the rest of delithiation. The plastic flow stress evolves continuously with lithium concentration. Thus, mechanical energy is dissipated in plastic deformation during both lithiation and delithiation, and it can be calculated from the stress measurements; we show that it is comparable to the polarization loss. Upon current interruption, both the film stress and the electrode potential relax with similar time constants, suggesting that stress contributes significantly to the chemical potential of lithiated silicon.

64

Experimental Demonstration of Quasi-Resonant Absorption in Silicon Thin Films for Enhanced Solar Light Trapping  

E-Print Network [OSTI]

We experimentally demonstrate that the addition of partial lattice disorder to a thin-film micro-crystalline silicon photonic crystal results in the controlled spectral broadening of its absorption peaks to form quasi resonances; increasing light trapping over a wide bandwidth while also reducing sensitivity to the angle of incident radiation. Accurate computational simulations are used to design the active-layer photonic crystal so as to maximize the number of its absorption resonances over the broadband interval where micro-crystalline silicon is weakly absorbing before lattice disorder augmented with fabrication-induced imperfections are applied to further boost performance. Such a design strategy may find practical use for increasing the efficiency of thin-film silicon photovoltaics.

Oskooi, Ardavan; Ishizaki, Kenji; Noda, Susumu

2013-01-01T23:59:59.000Z

65

Nanoporosity induced by ion implantation in deposited amorphous Ge thin films  

SciTech Connect (OSTI)

The formation of a nano-porous structure in amorphous Ge thin film (sputter-deposited on SiO{sub 2}) during ion irradiation at room temperature with 300 keV Ge{sup +} has been observed. The porous film showed a sponge-like structure substantially different from the columnar structure reported for ion implanted bulk Ge. The voids size and structure resulted to be strongly affected by the material preparation, while the volume expansion turned out to be determined only by the nuclear deposition energy. In SiGe alloys, the swelling occurs only if the Ge concentration is above 90%. These findings rely on peculiar characteristics related to the mechanism of voids nucleation and growth, but they are crucial for future applications of active nanostructured layers such as low cost chemical and biochemical sensing devices or electrodes in batteries.

Romano, L.; Impellizzeri, G.; Ruffino, F.; Miritello, M.; Grimaldi, M. G. [IMM-CNR MATIS and Dipartimento di Fisica e Astronomia, Universita di Catania, Via S. Sofia 64, I-95123 Catania (Italy); Bosco, L. [Scuola Superiore di Catania, Via Valdisavoia 9, I-95123 Catania (Italy)

2012-06-01T23:59:59.000Z

66

Fatigue failure in thin-film polycrystalline silicon is due to subcritical cracking within the oxide layer  

E-Print Network [OSTI]

Fatigue failure in thin-film polycrystalline silicon is due to subcritical cracking within with stress-induced surface oxide thicken- ing and moisture-assisted subcritical cracking in the amor- phous

Ritchie, Robert

67

Low-cost, deterministic quasi-periodic photonic structures for light trapping in thin film silicon solar cells  

E-Print Network [OSTI]

Light trapping has been an important issue for thin film silicon solar cells because of the low absorption coefficient in the near infrared range. In this paper, we present a photonic structure which combines anodic aluminum ...

Sheng, Xing

68

Pseudocrystalline model of the magnetic anisotropy in amorphous rare-earth–transition-metal thin films  

Science Journals Connector (OSTI)

A pseudocrystalline model is proposed to explain the occurrence of perpendicular anisotropy in amorphous rare-earth–transition metal (R-T) thin films. It is based on the central hypothesis that during layer-by-layer growth small planar hexagonal units are formed defining on average a preferential axis perpendicular to the film plane. The units are similar in structure to relaxed crystalline ones and are estimated to typically comprise six rare-earth atoms. They are regarded as an idealized model of the short-range order and are consistent with the known nearest-neighbor R-T and T-T coordination numbers in the amorphous state. This model is able to explain the known experimental results concerning the influence of composition, substrate temperature, annealing, and bombardment effects during sputter deposition on the magnetic anisotropy of thin amorphous rare-earth–transition-metal films of the system (Nd, Tb, Dy) (Fe, Co), as well as the destruction of this anisotropy by additives.

D. Mergel; H. Heitmann; P. Hansen

1993-01-01T23:59:59.000Z

69

NREL: Photovoltaics Research - Thin Film Photovoltaic Partnership Project  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Thin Film Photovoltaic Partnership Project Thin Film Photovoltaic Partnership Project NREL's Thin Film Photovoltaic (PV) Partnership Project led R&D on emerging thin-film solar technologies in the United States from 1994 to 2009. The project made many advances in thin-film PV technologies that allowed the United States to attain world leadership in this area of solar technology. Three national R&D teams focused on thin-film semiconductor materials: amorphous silicon (a-Si), cadmium telluride (CdTe), and copper indium gallium diselenide (CIGS) and its alloys. The Module Reliability Team and Environmental Health and Safety Team were crosscutting. The teams comprised researchers from the solar industry, academia, and NREL who focused their efforts on improving materials, devices, and manufacturing processes-all

70

Characterization of temperature-induced changes in amorphous hydrogenated carbon thin films  

Science Journals Connector (OSTI)

Abstract Hard hydrogenated amorphous carbon thin films were heated in vacuum to different temperatures and held at these for at least 30 min. Afterwards, the cooled-down samples were analyzed by various techniques. Strict and reproducible correlations were found between all the determined parameters and the annealing temperature. Single-wavelength ellipsometry shows that the real part of the refractive index of the films at 633 nm wavelength decreases with temperature while the extinction coefficient increases. It also shows swelling of the films with a thickness increase of about 50% for films heated to ? 1000 K. The associated decrease of mass density is proportional to the decrease in refractive index. Ion beam analysis shows that hydrogen is released from the films during heating with only about 5% of the initial H remaining after annealing at 1300 K while no significant loss of carbon can be detected. The losses of hydrogen during heating are monitored by temperature programmed desorption and they are in good agreement with the ion-beam-analysis results. Raman spectroscopy delivers evidence of aromatization of the films under heat treatment. Indication of first structural changes is found already at 600 K while the quickest changes of the refractive index, thickness, and hydrogen content with temperature occur around 850 K.

Christian Hopf; Thierry Angot; Etienne Aréou; Thomas Dürbeck; Wolfgang Jacob; Céline Martin; Cédric Pardanaud; Pascale Roubin; Thomas Schwarz-Selinger

2013-01-01T23:59:59.000Z

71

Properties of boron-doped thin films of polycrystalline silicon  

SciTech Connect (OSTI)

The properties of polycrystalline-silicon films deposited by low pressure chemical vapor deposition and doped heavily in situ boron-doped with concentration level of around 2×10{sup 20}cm{sup ?3} has been studied. Their properties are analyzed using electrical and structural characterization means by four points probe resistivity measurements and X-ray diffraction spectra. The thermal-oxidation process are performed on sub-micron layers of 200nm/c-Si and 200nm/SiO{sub 2} deposited at temperatures T{sub d} ranged between 520°C and 605°C and thermally-oxidized in dry oxygen ambient at 945°C. Compared to the as-grown resistivity with silicon wafers is known to be in the following sequence < and < . The measure X-ray spectra is shown, that the Bragg peaks are marked according to the crystal orientation in the film deposited on bare substrates (poly/c-Si), for the second series of films deposited on bare oxidized substrates (poly/SiO{sub 2}) are clearly different.

Merabet, Souad [Electronic Department, Faculty of Science and Technology, University of Jijel, Cité Ouled-Aissa B. P. 98 Jijel, 18 000 Jijel (Algeria)

2013-12-16T23:59:59.000Z

72

Plasmonic Back Structures Designed for Efficiency Enhancement of Thin Film Solar Cells  

Science Journals Connector (OSTI)

Metallic back structures with one-dimensional periodic nanoridges attached to thin-film amorphous silicon (a-Si) solar cell are proposed to enhance the cell efficiency in a wide...

Bai, Wenli; Gan, Qiaoqiang; Bartoli, Filbert; Song, Guofeng

73

Microcrystalline SiGe Absorber Layers in Thin-film Silicon Solar Cells  

Science Journals Connector (OSTI)

Abstract We report on physical properties of microcrystalline silicon-germanium (?c-SiGe:H) absorber layers for the use as a bottom structure in silicon based multijunction thin-film solar cells. Due to incorporation of Ge the absorption of the film is enhanced compared to pure ?c-Si:H films. This provides the opportunity to significantly reduce the absorber layer thickness. The experiments were carried out in a 13.56 MHz PECVD reactor using germane, silane and hydrogen as process gases. Single layers were characterized for their optical and electrical properties. Results from single and multijunction solar cells using a ?c- SiGe:H absorbers will be shown. In tandem solar cells a reduction of about 60% of the absorber layer thickness could be reached by using SiGe alloys compared to pristine silicon tandem cells.

K.V. Maydell; K. Grunewald; M. Kellermann; O. Sergeev; P. Klement; N. Reininghaus; T. Kilper

2014-01-01T23:59:59.000Z

74

Configuration Optimization of a Nanosphere Array on Top of a Thin Film Solar Cell  

E-Print Network [OSTI]

Configuration Optimization of a Nanosphere Array on Top of a Thin Film Solar Cell J. Grandidier on top of a solar cell can enhance light absorption and therefore increase its efficiency. Freely photocurrent of the solar cell. On a typical thin film amorphous silicon solar cell, a parametric analysis

Atwater, Harry

75

Thin-film silicon triple-junction solar cell with 12.5% stable efficiency on innovative flat light-scattering substrate  

E-Print Network [OSTI]

Thin-film silicon triple-junction solar cell with 12.5% stable efficiency on innovative flat light://jap.aip.org/about/rights_and_permissions #12;Thin-film silicon triple-junction solar cell with 12.5% stable efficiency on innovative flat light require light-trapping schemes that are predominantly based on depositing the solar cells on rough

Psaltis, Demetri

76

Pyroelectric response of lead zirconate titanate thin films on silicon: Effect of thermal stresses  

SciTech Connect (OSTI)

Ferroelectric lead zirconate titanate [Pb(Zr{sub x}Ti{sub 1-x}O){sub 3}, (PZT x:1-x)] has received considerable interest for applications related to uncooled infrared devices due to its large pyroelectric figures of merit near room temperature, and the fact that such devices are inherently ac coupled, allowing for simplified image post processing. For ferroelectric films made by industry-standard deposition techniques, stresses develop in the PZT layer upon cooling from the processing/growth temperature due to thermal mismatch between the film and the substrate. In this study, we use a non-linear thermodynamic model to investigate the pyroelectric properties of polycrystalline PZT thin films for five different compositions (PZT 40:60, PZT 30:70, PZT 20:80, PZT 10:90, PZT 0:100) on silicon as a function of processing temperature (25–800?°C). It is shown that the in-plane thermal stresses in PZT thin films alter the out-of-plane polarization and the ferroelectric phase transformation temperature, with profound effect on the pyroelectric properties. PZT 30:70 is found to have the largest pyroelectric coefficient (0.042??C cm{sup ?2}?°C{sup ?1}, comparable to bulk values) at a growth temperature of 550?°C; typical to what is currently used for many deposition processes. Our results indicate that it is possible to optimize the pyroelectric response of PZT thin films by adjusting the Ti composition and the processing temperature, thereby, enabling the tailoring of material properties for optimization relative to a specific deposition process.

Kesim, M. T.; Zhang, J.; Alpay, S. P. [Department of Materials Science and Engineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269 (United States); Trolier-McKinstry, S. [Department of Materials Science and Engineering and Materials Research Institute, Pennsylvania State University, Pennsylvania 16802 (United States); Mantese, J. V. [United Technologies Research Center, East Hartford, Connecticut 06118 (United States); Whatmore, R. W. [Tyndall National Institute, Lee Maltings, Dyke Parade, Cork City, County Cork (Ireland)

2013-11-28T23:59:59.000Z

77

High efficiency thin film silicon solar cells with novel light trapping : principle, design and processing  

E-Print Network [OSTI]

One major efficiency limiting factor in thin film solar cells is weak absorption of long wavelength photons due to the limited optical path length imposed by the thin film thickness. This is especially severe in Si because ...

Zeng, Lirong, Ph. D. Massachusetts Institute of Technology

2008-01-01T23:59:59.000Z

78

Ion beam assisted sputter deposition of ZnO for silicon thin-film solar cells  

Science Journals Connector (OSTI)

Ion beam assisted deposition (IBAD) is a promising technique for improving the material quality of ZnO-based thin films. The operation of an auxiliary Ar+ ion source during deposition of ZnO?:?Ga thin films by dc magnetron sputtering led to an improvement in crystalline texture, especially at low temperatures due to momentum transfer from the ions to the growing film. Etching of IBAD-ZnO?:?Ga films in diluted HCl revealed crater-like surface structures with crater diameters of up to 600 nm. These structures are usually achieved after deposition at high substrate temperatures. This is an indication that the grain structure was remarkably changed by bombarding these films during deposition in terms of increasing the compactness of the ZnO?:?Ga films. Subsequent annealing procedures led to an improvement in the electrical and optical properties. Hydrogenated microcrystalline silicon (µc-Si?:?H) solar cells exhibited enhanced efficiency as compared to cells on other low-temperature sputtered reference ZnO films. This improvement was ascribed to light trapping by the modified etching behaviour of the IBAD-ZnO?:?Ga films as well as improved transparency after the vacuum annealing step.

M Warzecha; D Köhl; M Wuttig; J Hüpkes

2014-01-01T23:59:59.000Z

79

Surface smoothing effect of an amorphous thin film deposited by atomic layer deposition on a surface with nano-sized roughness  

SciTech Connect (OSTI)

Previously, Lau (one of the authors) pointed out that the deposition of an amorphous thin film by atomic layer deposition (ALD) on a substrate with nano-sized roughness probably has a surface smoothing effect. In this letter, polycrystalline zinc oxide deposited by ALD onto a smooth substrate was used as a substrate with nano-sized roughness. Atomic force microscopy (AFM) and cross-sectional transmission electron microscopy (XTEM) were used to demonstrate that an amorphous aluminum oxide thin film deposited by ALD can reduce the surface roughness of a polycrystalline zinc oxide coated substrate.

Lau, W. S., E-mail: liuweicheng@zju.edu.cn; Wan, X.; Xu, Y.; Wong, H. [Zhejiang University, Department of Information Science and Electronic Engineering, No. 38 Zheda Road, Hangzhou 310027 (China)] [Zhejiang University, Department of Information Science and Electronic Engineering, No. 38 Zheda Road, Hangzhou 310027 (China); Zhang, J. [Zhejiang University, Department of Materials Science and Engineering, No. 38 Zheda Road, Hangzhou 310027 (China)] [Zhejiang University, Department of Materials Science and Engineering, No. 38 Zheda Road, Hangzhou 310027 (China); Luo, J. K. [Zhejiang University, Department of Information Science and Electronic Engineering, No. 38 Zheda Road, Hangzhou 310027 (China) [Zhejiang University, Department of Information Science and Electronic Engineering, No. 38 Zheda Road, Hangzhou 310027 (China); Institute of Renewable Energy and Environment Technology, Bolton University, Deane Road, Bolton BL3 5 AB (United Kingdom)

2014-02-15T23:59:59.000Z

80

Integrated All-silicon Thin-film Power Electronics on Flexible Sheets For Ubiquitous Wireless Charging Stations based on Solar-energy Harvesting  

E-Print Network [OSTI]

into wireless charging stations. In this work, we combine the thin-film circuits with flexible solar cellsIntegrated All-silicon Thin-film Power Electronics on Flexible Sheets For Ubiquitous Wireless Charging Stations based on Solar-energy Harvesting Liechao Huang, Warren Rieutort-Louis, Yingzhe Hu, Josue

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

A high performance thin film thermoelectric cooler  

SciTech Connect (OSTI)

Thin film thermoelectric devices with small dimensions have been fabricated using microelectronics technology and operated successfully in the Seebeck mode as sensors or generators. However, they do not operate successfully in the Peltier mode as coolers, because of the thermal bypass provided by the relatively thick substrate upon which the thermoelectric device is fabricated. In this paper a processing sequence is described which dramatically reduces this thermal bypass and facilitates the fabrication of high performance integrated thin film thermoelectric coolers. In the processing sequence a very thin amorphous SiC (or SiO{sub 2}SiN{sub 4}) film is deposited on a silicon substrate using conventional thin film deposition and a membrane formed by removing the silicon substrate over a desired region using chemical etching or micro-machining. Thermoelements are deposited on the membrane using conventional thin film deposition and patterning techniques and configured so that the region which is to be cooled is abutted to the cold junctions of the Peltier thermoelements while the hot junctions are located at the outer peripheral area which rests on the silicon substrate rim. Heat is pumped laterally from the cooled region to the silicon substrate rim and then dissipated vertically through it to an external heat sink. Theoretical calculations of the performance of a cooler described above indicate that a maximum temperature difference of about 40--50K can be achieved with a maximum heat pumping capacity of around 10 milliwatts.

Rowe, D.M.; Min, G.; Volklein, F.

1998-07-01T23:59:59.000Z

82

Structural properties of amorphous carbon thin films deposited by LF (100 kHz), RF (13.56 MHz), and pulsed RF (13.56 MHz) plasma CVD  

Science Journals Connector (OSTI)

Amorphous carbon thin films were deposited by LF (100 kHz), RF (13.56 MHz), and pulsed RF (13.56 MHz) plasma CVD with DC self-bias voltage of? ... properties of the deposited films in an asymmetric plasma reactor...

Dong-Sun Kim

2005-07-01T23:59:59.000Z

83

Radial distribution functions of amorphous silicon  

Science Journals Connector (OSTI)

Substantial changes in the radial distribution function of amorphous Si films have been observed in neutron-diffraction studies. The spectra indicate changes in short-range order associated with an ?11% modification in the bond-angle distribution width. The results allow the first direct comparison of structural and vibrational Raman probes of variations in local order in thin-film amorphous solids. Good agreement is obtained between the measured bond-angle variation and that based on Raman estimates.

J. Fortner and J. S. Lannin

1989-03-15T23:59:59.000Z

84

Spin-dependent processes in amorphous silicon-rich silicon-nitride S.-Y. Lee,1  

E-Print Network [OSTI]

diodes9 and a-Si:H solar cells.10 Fol- lowing coherent manipulation of paramagnetic centers, tran- sient-band , TSAMPLE=15 K. Dark and illuminated IV curves of the p-i-n devices were measured at room temperature and T amorphous silicon nitride a-SiNx:H has been used widely as a dielectric for thin-film transistors,1 solar

McCamey, Dane

85

Low work function, stable thin films  

DOE Patents [OSTI]

Generation of low work function, stable compound thin films by laser ablation. Compound thin films with low work function can be synthesized by simultaneously laser ablating silicon, for example, and thermal evaporating an alkali metal into an oxygen environment. For example, the compound thin film may be composed of Si/Cs/O. The work functions of the thin films can be varied by changing the silicon/alkali metal/oxygen ratio. Low work functions of the compound thin films deposited on silicon substrates were confirmed by ultraviolet photoelectron spectroscopy (UPS). The compound thin films are stable up to 500.degree. C. as measured by x-ray photoelectron spectroscopy (XPS). Tests have established that for certain chemical compositions and annealing temperatures of the compound thin films, negative electron affinity (NEA) was detected. The low work function, stable compound thin films can be utilized in solar cells, field emission flat panel displays, electron guns, and cold cathode electron guns.

Dinh, Long N. (Concord, CA); McLean, II, William (Oakland, CA); Balooch, Mehdi (Berkeley, CA); Fehring, Jr., Edward J. (Dublin, CA); Schildbach, Marcus A. (Livermore, CA)

2000-01-01T23:59:59.000Z

86

Chemical vapor deposition of hydrogenated amorphous silicon from disilane  

SciTech Connect (OSTI)

The authors describe hydrogenated amorphous silicon (a-Si:H) thin films deposited at growth rates of 1 to 30 A/s by chemical vapor deposition (CVD) from disilane source gas at 24 torr total pressure in a tubular reactor. The effects of substrate temperature and gas holding time (flow rate) on film growth rate and effluent gas composition were measured at temperatures ranging from 360{sup 0} to 485{sup 0}C and gas holding times from 3 to 62s. Effluent gases determined by gas chromatography included silane, disilane and other higher order silanes. A chemical reaction engineering model, based on a silylene (SiH/sub 2/) insertion gas phase reaction network and film growth from both SiH/sub 2/ and high molecular weight silicon species, Si/sub n/H/sub 2n/, was developed. The model predictions were in good agreement with experimentally determined growth rates and effluent gas compositions.

Bogaert, R.J.; Russell, T.W.F.; Klein, M.T. (Delaware Univ., Newark, DE (USA). Dept. of Chemical Engineering); Rocheleau, R.E.; Baron, B.N. (Delaware Univ., Newark, DE (USA). Inst. of Energy Conversion)

1989-10-01T23:59:59.000Z

87

Infrared laser-based monitoring of the silane dissociation during deposition of silicon thin films  

SciTech Connect (OSTI)

The silane dissociation efficiency, or depletion fraction, is an important plasma parameter by means of which the film growth rate and the amorphous-to-microcrystalline silicon transition regime can be monitored in situ. In this letter we implement a homebuilt quantum cascade laser-based absorption spectrometer to measure the silane dissociation efficiency in an industrial plasma-enhanced chemical vapor deposition system. This infrared laser-based diagnostic technique is compact, sensitive, and nonintrusive. Its resolution is good enough to resolve Doppler-broadened rotovibrational absorption lines of silane. The latter feature various absorption strengths, thereby enabling depletion measurements over a wide range of process conditions.

Bartlome, R.; Feltrin, A.; Ballif, C. [Ecole Polytechnique Federale de Lausanne (EPFL), Institute of Microengineering (IMT), Photovoltaics and Thin Film Electronics Laboratory, Rue A.-L. Breguet 2, 2000 Neuchatel (Switzerland)

2009-05-18T23:59:59.000Z

88

Influence of an anomalous dimension effect on thermal instability in amorphous-InGaZnO thin-film transistors  

SciTech Connect (OSTI)

This paper investigates abnormal dimension-dependent thermal instability in amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors. Device dimension should theoretically have no effects on threshold voltage, except for in short channel devices. Unlike short channel drain-induced source barrier lowering effect, threshold voltage increases with increasing drain voltage. Furthermore, for devices with either a relatively large channel width or a short channel length, the output drain current decreases instead of saturating with an increase in drain voltage. Moreover, the wider the channel and the shorter the channel length, the larger the threshold voltage and output on-state current degradation that is observed. Because of the surrounding oxide and other thermal insulating material and the low thermal conductivity of the IGZO layer, the self-heating effect will be pronounced in wider/shorter channel length devices and those with a larger operating drain bias. To further clarify the physical mechanism, fast I{sub D}-V{sub G} and modulated peak/base pulse time I{sub D}-V{sub D} measurements are utilized to demonstrate the self-heating induced anomalous dimension-dependent threshold voltage variation and on-state current degradation.

Liu, Kuan-Hsien; Chou, Wu-Ching, E-mail: tcchang3708@gmail.com, E-mail: wuchingchou@mail.nctu.edu.tw [Department of Electrophysics, National Chiao Tung University, Hsin-chu 300, Taiwan (China); Chang, Ting-Chang, E-mail: tcchang3708@gmail.com, E-mail: wuchingchou@mail.nctu.edu.tw [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Advanced Optoelectronics Technology Center, National Cheng Kung University, Taiwan (China); Chen, Hua-Mao; Tai, Ya-Hsiang [Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, Hsin-chu 300, Taiwan (China); Tsai, Ming-Yen; Hung, Pei-Hua; Chu, Ann-Kuo [Department of Photonics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Wu, Ming-Siou; Hung, Yi-Syuan [Department of Electronics Engineering, National Chiao Tung University, Hsin-Chu 300, Taiwan (China); Hsieh, Tien-Yu [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Yeh, Bo-Liang [Advanced Display Technology Research Center, AU Optronics, No.1, Li-Hsin Rd. 2, Hsinchu Science Park, Hsin-Chu 30078, Taiwan (China)

2014-10-21T23:59:59.000Z

89

Growth direction of oblique angle electron beam deposited silicon monoxide thin films identified by optical second-harmonic generation  

SciTech Connect (OSTI)

Oblique angle deposited (OAD) silicon monoxide (SiO) thin films forming tilted columnar structures have been characterized by second-harmonic generation. It was found that OAD SiO leads to a rotationally anisotropic second-harmonic response, depending on the optical angle of incidence. A model for the observed dependence of the second-harmonic signal on optical angle of incidence allows extraction of the growth direction of OAD films. The optically determined growth directions show convincing agreement with cross-sectional scanning electron microscopy images. In addition to a powerful characterization tool, these results demonstrate the possibilities for designing nonlinear optical devices through SiO OAD.

Vejling Andersen, Søren; Lund Trolle, Mads; Pedersen, Kjeld [Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4A, DK-9220 Aalborg Øst (Denmark)] [Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4A, DK-9220 Aalborg Øst (Denmark)

2013-12-02T23:59:59.000Z

90

Optical absorption in amorphous silicon  

SciTech Connect (OSTI)

The role that disorder plays in shaping the form of the optical absorption spectrum of hydrogenated amorphous silicon is investigated. Disorder leads to a redistribution of states, which both reduces the Tauc gap and broadens the absorption tail. The observed relationship between the Tauc gap and the breadth of the absorption tail is thus explained.

O`Leary, S.K.; Zukotynski, S.; Perz, J.M.; Sidhu, L.S. [Univ. of Toronto, Ontario (Canada). Dept. of Electrical and Computer Engineering

1996-12-31T23:59:59.000Z

91

Development of Commercial Technology for Thin Film Silicon Solar Cells on Glass: Cooperative Research and Development Final Report, CRADA Number CRD-07-209  

SciTech Connect (OSTI)

NREL has conducted basic research relating to high efficiency, low cost, thin film silicon solar cell design and the method of making solar cells. Two patents have been issued to NREL in the above field. In addition, specific process and metrology tools have been developed by NREL. Applied Optical Sciences Corp. (AOS) has expertise in the manufacture of solar cells and has developed its own unique concentrator technology. AOS wants to complement its solar cell expertise and its concentrator technology by manufacturing flat panel thin film silicon solar cell panels. AOS wants to take NREL's research to the next level, using it to develop commercially viable flat pane, thin film silicon solar cell panels. Such a development in equipment, process, and metrology will likely produce the lowest cost solar cell technology for both commercial and residential use. NREL's fundamental research capability and AOS's technology and industrial background are complementary to achieve this product development.

Sopori, B.

2013-03-01T23:59:59.000Z

92

Angular behavior of the absorption limit in thin film silicon solar cells  

E-Print Network [OSTI]

We investigate the angular behavior of the upper bound of absorption provided by the guided modes in thin film solar cells. We show that the 4n^2 limit can be potentially exceeded in a wide angular and wavelength range using two-dimensional periodic thin film structures. Two models are used to estimate the absorption enhancement; in the first one, we apply the periodicity condition along the thickness of the thin film structure but in the second one, we consider imperfect confinement of the wave to the device. To extract the guided modes, we use an automatized procedure which is established in this work. Through examples, we show that from the optical point of view, thin film structures have a high potential to be improved by changing their shape. Also, we discuss the nature of different optical resonances which can be potentially used to enhance light trapping in the solar cell. We investigate the two different polarization directions for one-dimensional gratings and we show that the transverse magnetic pola...

Naqavi, Ali; Söderström, Karin; Battaglia, Corsin; Paeder, Vincent; Scharf, Toralf; Herzig, Hans Peter; Ballif, Christophe

2013-01-01T23:59:59.000Z

93

Amorphous and crystalline phase formation in Ni/Al multilayer thin films  

SciTech Connect (OSTI)

The authors have investigated reactive phase formation in magnetron sputter-deposited Ni/Al multilayer films with a 1:3 molar ratio and various periodicities ranging from 320 nm to a codeposited film with an effective periodicity of zero. The films were studied by x-ray diffraction, differential scanning calorimetry, electrical resistance measurements, and transmission electron microscopy. The authors find that a reaction which results in the formation of an amorphous phase has taken place during the multilayer deposition process. This reaction substantially reduces the driving force for subsequent reactions and explains why nucleation kinetics become important for these reactions. The mode of transformation for a film with 10 nm periodicity was investigated, in detail, by applying the Johnson-Mehl-Avrami analysis to data obtained from isothermal and constant heating rate differential scanning calorimetry, in combination with electron microscopy studies of the transformation microstructure.

Lucadamo, G.; Barmak, K. [Lehigh Univ., Bethlehem, PA (United States). Dept. of Materials Science and Engineering; Michaelsen, C. [GKSS Research Center, Geesthacht (Germany). Inst. of Materials Research

1996-12-31T23:59:59.000Z

94

Hydrogen plasma treatment for improved conductivity in amorphous aluminum doped zinc tin oxide thin films  

SciTech Connect (OSTI)

Improving the conductivity of earth-abundant transparent conductive oxides (TCOs) remains an important challenge that will facilitate the replacement of indium-based TCOs. Here, we show that a hydrogen (H{sub 2})-plasma post-deposition treatment improves the conductivity of amorphous aluminum-doped zinc tin oxide while retaining its low optical absorption. We found that the H{sub 2}-plasma treatment performed at a substrate temperature of 50?°C reduces the resistivity of the films by 57% and increases the absorptance by only 2%. Additionally, the low substrate temperature delays the known formation of tin particles with the plasma and it allows the application of the process to temperature-sensitive substrates.

Morales-Masis, M., E-mail: monica.moralesmasis@epfl.ch; Ding, L.; Dauzou, F. [Photovoltaics and Thin-Film Electronics Laboratory (PVLab), Institute of Microengineering (IMT), Ecole Polytechnique Fédérale de Lausanne - EPFL, Rue de la Maladière 71b, CH-2002 Neuchatel (Switzerland); Jeangros, Q. [Interdisciplinary Centre for Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland); Hessler-Wyser, A. [Photovoltaics and Thin-Film Electronics Laboratory (PVLab), Institute of Microengineering (IMT), Ecole Polytechnique Fédérale de Lausanne - EPFL, Rue de la Maladière 71b, CH-2002 Neuchatel (Switzerland); Interdisciplinary Centre for Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland); Nicolay, S. [Centre Suisse d’Electronique et de Microtechnique (CSEM) SA, Rue Jaquet-Droz 1, CH-2002 Neuchatel (Switzerland); Ballif, C. [Photovoltaics and Thin-Film Electronics Laboratory (PVLab), Institute of Microengineering (IMT), Ecole Polytechnique Fédérale de Lausanne - EPFL, Rue de la Maladière 71b, CH-2002 Neuchatel (Switzerland); Centre Suisse d’Electronique et de Microtechnique (CSEM) SA, Rue Jaquet-Droz 1, CH-2002 Neuchatel (Switzerland)

2014-09-01T23:59:59.000Z

95

Narrow band gap amorphous silicon semiconductors  

DOE Patents [OSTI]

Disclosed is a narrow band gap amorphous silicon semiconductor comprising an alloy of amorphous silicon and a band gap narrowing element selected from the group consisting of Sn, Ge, and Pb, with an electron donor dopant selected from the group consisting of P, As, Sb, Bi and N. The process for producing the narrow band gap amorphous silicon semiconductor comprises the steps of forming an alloy comprising amorphous silicon and at least one of the aforesaid band gap narrowing elements in amount sufficient to narrow the band gap of the silicon semiconductor alloy below that of amorphous silicon, and also utilizing sufficient amounts of the aforesaid electron donor dopant to maintain the amorphous silicon alloy as an n-type semiconductor.

Madan, A.; Mahan, A.H.

1985-01-10T23:59:59.000Z

96

Growth, structure and electrical properties of epitaxial thulium silicide thin films on silicon  

SciTech Connect (OSTI)

Thulium silicide thin films were grown on (100) and (111) Si by evaporation of Tm metal and Si layers and annealing in a vacuum. Electron microscopy and x-ray diffraction results showed that the TmSi{sub 2{minus}x} layers are of high crystalline quality grown epitaxially on Si. Electrical resistivity measurements showed that TmSi{sub 2{minus}x} layers are metallic exhibiting magnetic ordering below 3 K. {copyright} {ital 1997 American Institute of Physics.}

Travlos, A.; Salamouras, N.; Boukos, N. [Institute of Materials Science, National Centre for Scientific Research Demokritos, Athens, (Greece) 15310] [Institute of Materials Science, National Centre for Scientific Research Demokritos, Athens, (Greece) 15310

1997-02-01T23:59:59.000Z

97

Atomistic modeling of amorphous silicon carbide using a bond...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

modeling of amorphous silicon carbide using a bond-order potential. Atomistic modeling of amorphous silicon carbide using a bond-order potential. Abstract: Molecular dynamics...

98

Irradiation-induced defect clustering and amorphization in silicon...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Irradiation-induced defect clustering and amorphization in silicon carbide. Irradiation-induced defect clustering and amorphization in silicon carbide. Abstract: Previous computer...

99

Optical approach to thermopower and conductivity measurements in thin-film semiconductors  

SciTech Connect (OSTI)

An optical beam deflection technique is applied to measure the Joule and Peltier heat generated by electric currents through thin-film semiconductors. The method yields a spatially resolved conductivity profile and allows the determination of Peltier coefficients. Results obtained on doped hydrogenated amorphous silicon films are presented.

Dersch, H.; Amer, N.M.

1984-08-01T23:59:59.000Z

100

Producer-Focused Life Cycle Assessment of Thin-Film Silicon Photovoltaic Systems  

E-Print Network [OSTI]

microcrystalline- silicon photovoltaic cell, B) range ofpayback of roof mounted photovoltaic cells. Boustead, I. andmicrocrystalline-silicon photovoltaic cell, B) range of

Zhang, Teresa Weirui

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Photochemical vapor deposition of amorphous silicon photovoltaic devices. Semiannual subcontract report, 1 May 1985-31 October 1985  

SciTech Connect (OSTI)

Intrinsic, p-type, and n-type hydrogenated amorphous silicon thin-films have been deposited by mercury-sensitized photochemical vapor deposition (photo-CVD) from disilane. The photochemical reactor design includes two chambers separated by a movable uv-transparent Teflon curtain to eliminate deposition on the reactor window. Glass/TCO/p-i-n/metal photovoltaic devices were fabricated by photo-CVD. The efficiency at 87.5 MW/cm/sup 2/(ELH) was 5.1%.

Baron, B.N.; Rocheleau, R.E.; Hegedus, S.S.

1986-06-01T23:59:59.000Z

102

Towards high efficiency thin-film crystalline silicon solar cells: The roles of light trapping and non-radiative recombinations  

SciTech Connect (OSTI)

Thin-film solar cells based on silicon have emerged as an alternative to standard thick wafers technology, but they are less efficient, because of incomplete absorption of sunlight, and non-radiative recombinations. In this paper, we focus on the case of crystalline silicon (c-Si) devices, and we present a full analytic electro-optical model for p-n junction solar cells with Lambertian light trapping. This model is validated against numerical solutions of the drift-diffusion equations. We use this model to investigate the interplay between light trapping, and bulk and surface recombination. Special attention is paid to surface recombination processes, which become more important in thinner devices. These effects are further amplified due to the textures required for light trapping, which lead to increased surface area. We show that c-Si solar cells with thickness of a few microns can overcome 20% efficiency and outperform bulk ones when light trapping is implemented. The optimal device thickness in presence of light trapping, bulk and surface recombination, is quantified to be in the range of 10–80??m, depending on the bulk quality. These results hold, provided the effective surface recombination is kept below a critical level of the order of 100?cm/s. We discuss the possibility of meeting this requirement, in the context of state-of-the-art techniques for light trapping and surface passivation. We show that our predictions are within the capability of present day silicon technologies.

Bozzola, A., E-mail: angelo.bozzola@unipv.it; Kowalczewski, P.; Andreani, L. C. [Physics Department, University of Pavia and CNISM, via Bassi 6, I-27100 Pavia (Italy)

2014-03-07T23:59:59.000Z

103

SunShot Initiative: Thin Film Photovoltaics Research  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Thin Film Photovoltaics Research Thin Film Photovoltaics Research to someone by E-mail Share SunShot Initiative: Thin Film Photovoltaics Research on Facebook Tweet about SunShot Initiative: Thin Film Photovoltaics Research on Twitter Bookmark SunShot Initiative: Thin Film Photovoltaics Research on Google Bookmark SunShot Initiative: Thin Film Photovoltaics Research on Delicious Rank SunShot Initiative: Thin Film Photovoltaics Research on Digg Find More places to share SunShot Initiative: Thin Film Photovoltaics Research on AddThis.com... Concentrating Solar Power Photovoltaics Research & Development Crystalline Silicon Thin Films Multijunctions Organic Photovoltaics Dye-Sensitized Solar Cells Competitive Awards Systems Integration Balance of Systems Thin Film Photovoltaics Research The U.S. Department of Energy (DOE) supports research and development of

104

High-rate deposition of hydrogenated amorphous silicon films and devices  

SciTech Connect (OSTI)

This report summarizes the status of high-rate deposition technologies associated with amorphous silicon thin films for photovoltaic applications. The report lists (1) deposition rates for a-Si:H films according to source and method and (2) efficiencies and other parameters of a-Si:H solar cells. Two main deposition source materials, silane and disilane, are discussed, as well as effects of boron doping. The effects of various deposition parameters on film characteristics and on deposition rate are presented, as well as the effects of annealing on high-deposition-rate films. Light-induced effects are also discussed. Finally, progress and problems in this field of study are summarized.

Luft, W.

1987-04-01T23:59:59.000Z

105

Phonon renormalization and Raman spectral evolution through amorphous to crystalline transitions in Sb{sub 2}Te{sub 3} thin films  

SciTech Connect (OSTI)

A symmetry specific phonon mode renormalization is observed across an amorphous to crystalline phase transformation in thin films of the topological material Sb{sub 2}Te{sub 3} using Raman spectroscopy. We present evidence for local crystalline symmetry in the amorphous state, eventhough, the q?=?0 Raman selection rule is broken due to strong structural disorder. At crystallization, the in-plane polarized (E{sub g}{sup 2}) mode abruptly sharpens while the out-of-plane polarized (A{sub 1g}) modes are only weakly effected. This effect unique to the E{sub g} symmetry is exceptional considering that polarized spectra and comparison of the single phonon density of states between the amorphous and crystalline phases suggest that short range order of the amorphous phase is, on the average, similar to that of the crystalline material while electrical transport measurements reveal a sharp insulator-to-metal transition. Our findings point to the important role of anisotropic disorder affecting potential applications of topological and phase-change based electronics.

Secor, Jeff; Zhao, Lukas; Krusin-Elbaum, Lia [The Graduate Center, CUNY, New York, New York 10016 (United States); Department of Physics, The City College of New York, CUNY, New York, New York 10031 (United States); Harris, Matt A.; Deng, Haiming [Department of Physics, The City College of New York, CUNY, New York, New York 10031 (United States); Raoux, Simone [IBM T. J. Watson Research Center, Yorktown Heights, New York 10598 (United States)

2014-06-02T23:59:59.000Z

106

Method for formation of thin film transistors on plastic substrates  

DOE Patents [OSTI]

A process for formation of thin film transistors (TFTs) on plastic substrates replaces standard thin film transistor fabrication techniques, and uses sufficiently lower processing temperatures so that inexpensive plastic substrates may be used in place of standard glass, quartz, and silicon wafer-based substrates. The process relies on techniques for depositing semiconductors, dielectrics, and metals at low temperatures; crystallizing and doping semiconductor layers in the TFT with a pulsed energy source; and creating top-gate self-aligned as well as back-gate TFT structures. The process enables the fabrication of amorphous and polycrystalline channel silicon TFTs at temperatures sufficiently low to prevent damage to plastic substrates. The process has use in large area low cost electronics, such as flat panel displays and portable electronics.

Carey, Paul G. (Mountain View, CA); Smith, Patrick M. (San Ramon, CA); Sigmon, Thomas W. (Portola Valley, CA); Aceves, Randy C. (Livermore, CA)

1998-10-06T23:59:59.000Z

107

Method for formation of thin film transistors on plastic substrates  

DOE Patents [OSTI]

A process for formation of thin film transistors (TFTs) on plastic substrates replaces standard thin film transistor fabrication techniques, and uses sufficiently lower processing temperatures so that inexpensive plastic substrates may be used in place of standard glass, quartz, and silicon wafer-based substrates. The process relies on techniques for depositing semiconductors, dielectrics, and metals at low temperatures; crystallizing and doping semiconductor layers in the TFT with a pulsed energy source; and creating top-gate self-aligned as well as back-gate TFT structures. The process enables the fabrication of amorphous and polycrystalline channel silicon TFTs at temperatures sufficiently low to prevent damage to plastic substrates. The process has use in large area low cost electronics, such as flat panel displays and portable electronics. 5 figs.

Carey, P.G.; Smith, P.M.; Sigmon, T.W.; Aceves, R.C.

1998-10-06T23:59:59.000Z

108

Crystallization and doping of amorphous silicon on low temperature plastic  

DOE Patents [OSTI]

A method or process of crystallizing and doping amorphous silicon (a-Si) on a low-temperature plastic substrate using a short pulsed high energy source in a selected environment, without heat propagation and build-up in the substrate. The pulsed energy processing of the a-Si in a selected environment, such as BF3 and PF5, will form a doped micro-crystalline or poly-crystalline silicon (pc-Si) region or junction point with improved mobilities, lifetimes and drift and diffusion lengths and with reduced resistivity. The advantage of this method or process is that it provides for high energy materials processing on low cost, low temperature, transparent plastic substrates. Using pulsed laser processing a high (>900.degree. C.), localized processing temperature can be achieved in thin films, with little accompanying temperature rise in the substrate, since substrate temperatures do not exceed 180.degree. C. for more than a few microseconds. This method enables use of plastics incapable of withstanding sustained processing temperatures (higher than 180.degree. C.) but which are much lower cost, have high tolerance to ultraviolet light, have high strength and good transparency, compared to higher temperature plastics such as polyimide.

Kaschmitter, James L. (Pleasanton, CA); Truher, Joel B. (Palo Alto, CA); Weiner, Kurt H. (Campbell, CA); Sigmon, Thomas W. (Beaverton, OR)

1994-01-01T23:59:59.000Z

109

Experimental Investigation of Size Effects on the Thermal Conductivity of Silicon-Germanium Alloy Thin Films  

E-Print Network [OSTI]

We experimentally investigate the role of size effects and boundary scattering on the thermal conductivity of silicon-germanium alloys. The thermal conductivities of a series of epitaxially grown Si[subscript 1-x] Ge[subscript ...

Cheaito, Ramez

110

Deposition and characterization of polycrystalline silicon films on glass for thin film solar cells  

SciTech Connect (OSTI)

The authors deposit phosphorus-doped, amorphous Si by low pressure chemical vapor deposition and subsequently crystallize the films by furnace annealing at a temperature of 600 C. Optical in-situ monitoring allows one to control the crystallization process. Phosphorus doping leads to faster crystallization and a grain size enhancement with a maximum grain size of 15 {micro}m. Using transmission electron microscopy they find a log-normal grain size distribution in their films. They demonstrate that this distribution not only arises from solid phase crystallization of amorphous Si but also from other crystallization processes based on random nucleation and growth. The log-normal grain size distribution seems to be a general feature of polycrystalline semiconductors.

Bergmann, R.B.; Krinke, J.; Strunk, H.P.; Werner, J.H.

1997-07-01T23:59:59.000Z

111

LOSS ANALYSIS OF BACK-CONTACT BACK-JUNCTION THIN-FILM MONOCRYSTALLINE SILICON SOLAR CELLS  

E-Print Network [OSTI]

- dimensional finite element modeling with a resistance network simulation. The simulated and measured current of the best cell with 13.5 % efficiency is the high saturation current density at the metal-silicon interface significance of various loss mechan- isms. This analysis is the purpose of this contribution. Standard

112

Flexible Solar-Energy Harvesting System on Plastic with Thin-film LC Oscillators Operating Above ft for  

E-Print Network [OSTI]

Flexible Solar-Energy Harvesting System on Plastic with Thin-film LC Oscillators Operating Above ft- This paper presents an energy-harvesting system consisting of amorphous-silicon (a-Si) solar cells and thin of the energy-harvesting system. The solar module consists of solar cells in series operating at an output

113

Cooling of hot electrons in amorphous silicon  

SciTech Connect (OSTI)

Measurements of the cooling rate of hot carriers in amorphous silicon are made with a two-pump, one-probe technique. The experiment is simulated with a rate-equation model describing the energy transfer between a population of hot carriers and the lattice. An energy transfer rate proportional to the temperature difference is found to be consistent with the experimental data while an energy transfer independent of the temperature difference is not. This contrasts with the situation in crystalline silicon. The measured cooling rates are sufficient to explain the difficulty in observing avalanche effects in amorphous silicon.

Vanderhaghen, R.; Hulin, D.; Cuzeau, S.; White, J.O.

1997-07-01T23:59:59.000Z

114

Model of thermally activated magnetization reversal in thin films of amorphous rare-earth-transition-metal alloys  

Science Journals Connector (OSTI)

Monte Carlo simulations on a two-dimensional lattice of magnetic dipoles have been performed to investigate the magnetic reversal by thermal activation in rare-earth-transition-metal (RE-TM) alloys. Three mechanisms of magnetization reversal were observed: nucleation dominated growth, nucleation followed by the growth of magnetic domains containing no seeds of unreversed magnetization, and nucleation followed by dendritic domain growth by successive branching in the motion of the domain walls. The domain structures are not fractal; however, the fractal dimension of the domain wall was found to be a good measure of the jaggedness of the domain boundary surface during the growth process. The effects of the demagnetizing field on the hysteretic and time-dependent properties of the thin films were studied and some limitations in the application of the Fatuzzo model on magneto-optic media are identified.

A. Lyberatos; J. Earl; R. W. Chantrell

1996-03-01T23:59:59.000Z

115

Effective phase control of silicon films during high-rate deposition in atmospheric-pressure very high-frequency plasma: Impacts of gas residence time on the performance of bottom-gate thin film transistors  

Science Journals Connector (OSTI)

Abstract Hydrogenated amorphous silicon (a-Si) and microcrystalline silicon (?c-Si) films were grown in atmospheric-pressure (AP) He/H2/SiH4 plasma excited by a 150-MHz very high-frequency (VHF) power at a temperature of 220 °C. The variations in thickness and crystallinity of the deposited Si films along the gas flow direction were studied as functions of gas residence time in the plasma, VHF power density and H2 flow rate. Furthermore, the electrical characteristics of bottom-gate thin film transistors (TFTs) were investigated to evaluate the film quality. The results revealed that the chemical reactions both in gas phase and on the growing film surface were significantly enhanced in AP-VHF plasma, promoting phase transition from amorphous to microcrystalline in a time of the order of 0.1 ms. The performance of the \\{TFTs\\} showed that a-Si layers formed in the upstream portion of the plasma zone had reasonably good electrical property (field-effect mobility of approximately 2 cm2/V s) despite very high deposition rates around 20 nm/s. While ?c-Si layers deposited in the downstream portion were very defective, which might come from the insufficient passivation of grain boundaries with a-Si tissues due to a too long gas residence time in the plasma. The precise control of gas residence time by adjusting the length of plasma will be effective for the phase control of Si films with desired quality.

H. Kakiuchi; H. Ohmi; T. Yamada; A. Hirano; T. Tsushima; W. Lin; K. Yasutake

2013-01-01T23:59:59.000Z

116

Thin Film Transistors On Plastic Substrates  

DOE Patents [OSTI]

A process for formation of thin film transistors (TFTs) on plastic substrates replaces standard thin film transistor fabrication techniques, and uses sufficiently lower processing temperatures so that inexpensive plastic substrates may be used in place of standard glass, quartz, and silicon wafer-based substrates. The silicon based thin film transistor produced by the process includes a low temperature substrate incapable of withstanding sustained processing temperatures greater than about 250.degree. C., an insulating layer on the substrate, a layer of silicon on the insulating layer having sections of doped silicon, undoped silicon, and poly-silicon, a gate dielectric layer on the layer of silicon, a layer of gate metal on the dielectric layer, a layer of oxide on sections of the layer of silicon and the layer of gate metal, and metal contacts on sections of the layer of silicon and layer of gate metal defining source, gate, and drain contacts, and interconnects.

Carey, Paul G. (Mountain View, CA); Smith, Patrick M. (San Ramon, CA); Sigmon, Thomas W. (Portola Valley, CA); Aceves, Randy C. (Livermore, CA)

2004-01-20T23:59:59.000Z

117

Thin, High Lifetime Silicon Wafers with No Sawing; Re-crystallization in a Thin Film Capsule  

SciTech Connect (OSTI)

The project fits within the area of renewable energy called photovoltaics (PV), or the generation of electricity directly from sunlight using semiconductor devices. PV has the greatest potential of any renewable energy technology. The vast majority of photovoltaic modules are made on crystalline silicon wafers and these wafers accounts for the largest fraction of the cost of a photovoltaic module. Thus, a method of making high quality, low cost wafers would be extremely beneficial to the PV industry The industry standard technology creates wafers by casting an ingot and then sawing wafers from the ingot. Sawing rendered half of the highly refined silicon feedstock as un-reclaimable dust. Being a brittle material, the sawing is actually a type of grinding operation which is costly both in terms of capital equipment and in terms of consumables costs. The consumables costs associated with the wire sawing technology are particularly burdensome and include the cost of the wire itself (continuously fed, one time use), the abrasive particles, and, waste disposal. The goal of this project was to make wafers directly from molten silicon with no sawing required. The fundamental concept was to create a very low cost (but low quality) wafer of the desired shape and size and then to improve the quality of the wafer by a specialized thermal treatment (called re-crystallization). Others have attempted to create silicon sheet by recrystallization with varying degrees of success. Key among the difficulties encountered by others were: a) difficulty in maintaining the physical shape of the sheet during the recrystallization process and b) difficulty in maintaining the cleanliness of the sheet during recrystallization. Our method solved both of these challenges by encapsulating the preform wafer in a protective capsule prior to recrystallization (see below). The recrystallization method developed in this work was extremely effective at maintaining the shape and the cleanliness of the wafer. In addition, it was found to be suitable for growing very large crystals. The equipment used was simple and inexpensive to operate. Reasonable solar cells were fabricated on re-crystallized material.

Emanuel Sachs

2013-01-16T23:59:59.000Z

118

Amorphous silicon detectors in positron emission tomography  

SciTech Connect (OSTI)

The physics of the detection process is studied and the performances of different Positron Emission Tomography (PET) system are evaluated by theoretical calculation and/or Monte Carlo Simulation (using the EGS code) in this paper, whose table of contents can be summarized as follows: a brief introduction to amorphous silicon detectors and some useful equation is presented; a Tantalum/Amorphous Silicon PET project is studied and the efficiency of the systems is studied by Monte Carlo Simulation; two similar CsI/Amorphous Silicon PET projects are presented and their efficiency and spatial resolution are studied by Monte Carlo Simulation, light yield and time characteristics of the scintillation light are discussed for different scintillators; some experimental result on light yield measurements are presented; a Xenon/Amorphous Silicon PET is presented, the physical mechanism of scintillation in Xenon is explained, a theoretical estimation of total light yield in Xenon and the resulting efficiency is discussed altogether with some consideration of the time resolution of the system; the amorphous silicon integrated electronics is presented, total noise and time resolution are evaluated in each of our applications; the merit parameters {epsilon}{sup 2}{tau}'s are evaluated and compared with other PET systems and conclusions are drawn; and a complete reference list for Xenon scintillation light physics and its applications is presented altogether with the listing of the developed simulation programs.

Conti, M. (Istituto Nazionale di Fisica Nucleare, Pisa (Italy) Lawrence Berkeley Lab., CA (USA)); Perez-Mendez, V. (Lawrence Berkeley Lab., CA (USA))

1989-12-01T23:59:59.000Z

119

Crystallization to polycrystalline silicon thin film and simultaneous inactivation of electrical defects by underwater laser annealing  

SciTech Connect (OSTI)

We propose a low-temperature laser annealing method of a underwater laser annealing (WLA) for polycrystalline silicon (poly-Si) films. We performed crystallization to poly-Si films by laser irradiation in flowing deionized-water where KrF excimer laser was used for annealing. We demonstrated that the maximum value of maximum grain size of WLA samples was 1.5 {mu}m, and that of the average grain size was 2.8 times larger than that of conventional laser annealing in air (LA) samples. Moreover, WLA forms poly-Si films which show lower conductivity and larger carrier life time attributed to fewer electrical defects as compared to LA poly-Si films.

Machida, Emi [Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma, Nara 630-0192 (Japan); Research Fellowships of the Japan Society for the Promotion of Science, Japan Society for the Promotion of Science, 1-8 Chiyoda, Tokyo 102-8472 (Japan); Horita, Masahiro; Ishikawa, Yasuaki; Uraoka, Yukiharu [Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma, Nara 630-0192 (Japan); Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Honcho, Kawaguchi, Saitama 332-0012 (Japan); Ikenoue, Hiroshi [Graduate School of Information Science and Electrical Engineering, Kyushu University, 744 Motooka Nishi-ku, Fukuoka 819-0395 (Japan)

2012-12-17T23:59:59.000Z

120

AMORPHOUS SILICON-BASED MINIMODULES WITH SILICONE ELASTOMER ENCAPSULATION  

E-Print Network [OSTI]

fabricated one and two cell, amorphous silicon based mini-modules encapsulated with a modern silicone. The first module consisted of a single cell with a current collecting grid and bus bars on two sides of the cell. The current collecting grid used a spacing of 1 cm. 250 µm diameter tinned copper wire was used

Deng, Xunming

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Amorphization of Silicon Carbide by Carbon Displacement. | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of Silicon Carbide by Carbon Displacement. Amorphization of Silicon Carbide by Carbon Displacement. Abstract: We have used molecular dynamics simulations to examine the possibility...

122

Muon States in Polycrystalline and Amorphous Silicon [and Discussion  

Science Journals Connector (OSTI)

15 February 1995 research-article Muon States in Polycrystalline and Amorphous Silicon [and Discussion] E. A. Davis A. Singh S. F. J. Cox A. M. Stoneham M. Symons Muons implanted into polycrystalline and amorphous silicon have been...

1995-01-01T23:59:59.000Z

123

Study of spontaneous and induced absorption in amorphous Ta{sub 2}O{sub 5} and SiO{sub 2} dielectric thin films  

SciTech Connect (OSTI)

Tantalum pentoxide (Ta{sub 2}O{sub 5}) and silicon dioxide (SiO{sub 2}) are common high-index and low-index materials used in dielectric optical coatings for high average-power lasers since high-density sputtered oxide films with absorption losses at near- and mid-infrared wavelengths of less than 1 ppm can be obtained. These oxides have been chosen to investigate the spontaneous and optically induced absorption at {lambda}{sub 0} = 1064 nm that occurs due to simultaneous illumination at shorter wavelengths. The effect is measured using the photothermal common-path interferometric technique. This technique is capable of detecting sub-ppm levels of optical absorption and tracking its changes at a given wavelength when a second laser beam is also incident on a thin film oxide sample. In this work, dual beam experiments are employed to assess changes in the optical absorption at {lambda}{sub 0} = 1064 nm in ion beam sputtered Ta{sub 2}O{sub 5} and SiO{sub 2} thin films deposited on fused silica substrates, with stimulating illumination {lambda}{sub 1} ranging from {lambda}{sub 1} = 266 nm to {lambda}{sub 1} = 780 nm. The power and wavelength of the stimulating radiation were found to affect the optical absorption at {lambda}{sub 0} = 1064 nm. Furthermore, the relaxation dynamics of the induced infrared absorption was found to be wavelength dependent and is thought to be associated with various electron traps existing in the forbidden gap that depend essentially on the film's preparation conditions. The significantly greater effect observed in Ta{sub 2}O{sub 5} at {lambda}{sub 1} = 266 nm is attributed to band-to-band transitions.

Markosyan, A. S.; Route, R.; Fejer, M. M. [Department of Applied Physics, E.L. Ginzton Laboratory, Stanford University, Stanford, California 94305 (United States); Patel, D.; Menoni, C. [Department of Electrical and Computer Engineering and NSF ERC for Extreme Ultraviolet Science and Technology, Colorado State University, Fort Collins, Colorado 80523 (United States)

2013-04-07T23:59:59.000Z

124

Amorphous Silicon Based Neutron Detector  

SciTech Connect (OSTI)

Various large-scale neutron sources already build or to be constructed, are important for materials research and life science research. For all these neutron sources, neutron detectors are very important aspect. However, there is a lack of a high-performance and low-cost neutron beam monitor that provides time and temporal resolution. The objective of this SBIR Phase I research, collaboratively performed by Midwest Optoelectronics, LLC (MWOE), the University of Toledo (UT) and Oak Ridge National Laboratory (ORNL), is to demonstrate the feasibility for amorphous silicon based neutron beam monitors that are pixilated, reliable, durable, fully packaged, and fabricated with high yield using low-cost method. During the Phase I effort, work as been focused in the following areas: 1) Deposition of high quality, low-defect-density, low-stress a-Si films using very high frequency plasma enhanced chemical vapor deposition (VHF PECVD) at high deposition rate and with low device shunting; 2) Fabrication of Si/SiO2/metal/p/i/n/metal/n/i/p/metal/SiO2/ device for the detection of alpha particles which are daughter particles of neutrons through appropriate nuclear reactions; and 3) Testing of various devices fabricated for alpha and neutron detection; As the main results: · High quality, low-defect-density, low-stress a-Si films have been successfully deposited using VHF PECVD on various low-cost substrates; · Various single-junction and double junction detector devices have been fabricated; · The detector devices fabricated have been systematically tested and analyzed. · Some of the fabricated devices are found to successfully detect alpha particles. Further research is required to bring this Phase I work beyond the feasibility demonstration toward the final prototype devices. The success of this project will lead to a high-performance, low-cost, X-Y pixilated neutron beam monitor that could be used in all of the neutron facilities worldwide. In addition, the technologies developed here could be used to develop X-ray and neutron monitors that could be used in the future for security checks at the airports and other critical facilities. The project would lead to devices that could significantly enhance the performance of multi-billion dollar neutron source facilities in the US and bring our nation to the forefront of neutron beam sciences and technologies which have enormous impact to materials, life science and military research and applications.

Xu, Liwei

2004-12-12T23:59:59.000Z

125

Adaptation of thin-film photovoltaic technology for use in space  

SciTech Connect (OSTI)

The anticipated deployment of large numbers of satellites in low earth orbit (LEO) for global telecommunications networks renews interest in producing solar power systems that are lightweight, robust, resistant to radiation damage, and relatively inexpensive. Promising near term thin-film candidates are amorphous silicon (a-Si), cadmium telluride (CdTe), and copper indium gallium diselenide (CIGS). The authors discuss the modifications that are necessary to adapt terrestrial thin-film technology for use in space. The authors characterize expected module performance and present results of tests performed on sample cells. They consider the possibility of achieving aggressive cost, weight, and performance targets through the use of thin-film photovoltaic (PV) technology.

Fairbanks, E.S.; Gates, M.T. [Boeing Commercial Space Co., Seattle, WA (United States)

1997-12-31T23:59:59.000Z

126

The deposition of nanocrystalline TiO2 thin film on silicon using Sol-Gel technique and its characterization  

Science Journals Connector (OSTI)

TiO"2 thin films were deposited using Sol-Gel spin coating technique using titanium isoperoxide as the Titania precursor. The films were characterized using X-ray diffraction, capacitance voltage measurement and Raman characterization technique. The ... Keywords: Sol-Gel, Spin coating, Titanium dioxide, X-ray diffraction

Mukesh Kumar; Mukesh Kumar; Dinesh Kumar

2010-03-01T23:59:59.000Z

127

Microcrystalline silicon germanium: An attractive bottom-cell material for thin-film silicon-based tandem-solar-cells  

SciTech Connect (OSTI)

The authors have prepared hydrogenated microcrystalline silicon germanium by plasma enhanced CVD of a mixture of silane and germane gas diluted with hydrogen. The growth conditions have been systematically controlled to obtain large ({approximately}400{angstrom}) crystallites of silicon-germanium as observed using Raman scattering and x-ray diffraction. The dangling bond (germanium) density has been reduced to <5 x 10{sup 16} cm{sup {minus}3} at low substrate temperatures ({approximately}150 C). The optical absorption spectra of the 50% Ge containing material is red-shifted compared to microcrystalline silicon, consistent with a reduction of the indirect optical gap to 0.9 eV. Schottky type cells fabricated using Au on an n{sup +} crystalline silicon substrate confirm that the long wavelength response is remarkably enhanced in this material.

Ganguly, Gautam; Ikeda, Toru; Kajiwara, Kei; Matduda, Akihisa

1997-07-01T23:59:59.000Z

128

E-Print Network 3.0 - amorphous silicon carbon Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

is changing from a cross-linked diamond-like carbon material to an amorphous silicon carbide material... with silicon. 1. Introduction Amorphous hydrogenated silicon carbide...

129

ITO, Si3N4 and ZnO: Al -- Simulation of Different Anti-reflection Coatings (ARC) for Thin Film a-Si:H Solar Cells  

Science Journals Connector (OSTI)

For thin film solar cells incorporating amorphous silicon (a-Si:H) as absorber materials, minimizing reflection from the top surface i.e. maximizing transmittance of the incoming light into the absorber for higher absorption plays an important role for ... Keywords: ARC, TCO, ITO, Si3N4, ZnO:Al, Solar cell

Kazi Islam; Aaesha Alnuaimi; Helmy Ally; Ammar Nayfeh

2013-11-01T23:59:59.000Z

130

Ion bombardment and disorder in amorphous silicon  

SciTech Connect (OSTI)

The effect of ion bombardment during growth on the structural and optical properties of amorphous silicon are presented. Two series of films were deposited under electrically grounded and positively biased substrate conditions. The biased samples displayed lower growth rates and increased hydrogen content relative to grounded counterparts. The film structure was examined using Raman spectroscopy. The transverse optic like phonon band position was used as a parameter to characterize network order. Biased samples displayed an increased order of the amorphous network relative to grounded samples. Furthermore, biased samples exhibited a larger optical gap. These results are correlated and attributed to reduced ion bombardment effects.

Sidhu, L.S.; Gaspari, F.; Zukotynski, S.

1997-07-01T23:59:59.000Z

131

Photovoltaic Polycrystalline Thin-Film Cell Basics | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Polycrystalline Thin-Film Cell Basics Polycrystalline Thin-Film Cell Basics Photovoltaic Polycrystalline Thin-Film Cell Basics August 20, 2013 - 2:36pm Addthis Polycrystalline thin-film cells are made of many tiny crystalline grains of semiconductor materials. The materials used in these cells have properties that are different from those of silicon. Thin-film cells have many advantages over their thick-film counterparts. For example, they use much less material. The cell's active area is usually only 1 to 10 micrometers thick, whereas thick films typically are 100 to 300 micrometers thick. Also, thin-film cells can usually be manufactured in a large-area process, which can be an automated, continuous production process. Finally, they can be deposited on flexible substrate materials. The term thin film comes from the method used to deposit the film, not from

132

Thin-film Rechargeable Lithium Batteries  

DOE R&D Accomplishments [OSTI]

Thin film rechargeable lithium batteries using ceramic electrolyte and cathode materials have been fabricated by physical deposition techniques. The lithium phosphorous oxynitride electrolyte has exceptional electrochemical stability and a good lithium conductivity. The lithium insertion reaction of several different intercalation materials, amorphous V{sub 2}O{sub 5}, amorphous LiMn{sub 2}O{sub 4}, and crystalline LiMn{sub 2}O{sub 4} films, have been investigated using the completed cathode/electrolyte/lithium thin film battery.

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

1995-06-00T23:59:59.000Z

133

Technology of Amorphous Silicon Thin Films for Solar Cells and Applications to Power Systems  

Science Journals Connector (OSTI)

Preliminary attempts have been made to grow non-hydrogenated a-Si films by evaporation in an ordinary vacuum system (ultimate pressure 10?6 Toor) fitted with a six-hearth electron gun and a substrate heater. This...

D. Girginoudi; A. Thanailakis; P. Abarian…

1983-01-01T23:59:59.000Z

134

Deuterium in crystalline and amorphous silicon  

SciTech Connect (OSTI)

The authors report deuteron magnetic resonance (DMR) measurements on aged deuterium-implanted single crystal n-type silicon and comparisons with amorphous silicon spectra. The sample film was prepared six years ago by deuteration from a-D{sub 2} plasma and evaluated by a variety of experimental methods. Deuterium has been evolving with time and the present DMR signal shows a smaller deuteron population. A doublet from Si-D configurations along (111) has decreased more than have central molecular DMR components, which include 47 and 12 kHz FWHM gaussians. Transient DMR magnetization recoveries indicate spin lattice relaxation to para-D{sub 2} relaxation centers.

Borzi, R.; Ma, H.; Fedders, P.A.; Leopold, D.J.; Norberg, R.E.; Boyce, J.B.; Johnson, N.M.; Ready, S.E.; Walker, J.

1997-07-01T23:59:59.000Z

135

Bonding defects in hydrogenated amorphous silicon  

SciTech Connect (OSTI)

A mechanism for charged-carrier-trapping-induced defect metastability in hydrogenated amorphous silicon (a-Si:H) and in hydrogenated amorphous silicon alloys containing relatively high concentrations of oxygen and/or nitrogen atoms (a-Si:X:H, X = O or N) is described. The experimental results that identified this defect metastability mechanism were (i) differences in the Staebler-Wronski effect in a-Si:H and a-Si:N:H alloys prepared from N{sub 2} and NH{sub 3} source gases by remote plasma-enhanced chemical-vapor deposition, and (ii) differences in defect generation at N-atom terminated Si-SiO{sub 2} interfaces prepared from NH{sub 3} and N{sub 2}O.

Lucovsky, G.; Yang, H. [North Carolina State Univ., Raleigh, NC (United States)

1996-12-31T23:59:59.000Z

136

High resolution amorphous silicon radiation detectors  

DOE Patents [OSTI]

A radiation detector employing amorphous Si:H cells in an array with each detector cell having at least three contiguous layers (n type, intrinsic, p type), positioned between two electrodes to which a bias voltage is applied. An energy conversion layer atop the silicon cells intercepts incident radiation and converts radiation energy to light energy of a wavelength to which the silicon cells are responsive. A read-out device, positioned proximate to each detector element in an array allows each such element to be interrogated independently to determine whether radiation has been detected in that cell. The energy conversion material may be a layer of luminescent material having a columnar structure. In one embodiment a column of luminescent material detects the passage therethrough of radiation to be detected and directs a light beam signal to an adjacent a-Si:H film so that detection may be confined to one or more such cells in the array. One or both electrodes may have a comb structure, and the teeth of each electrode comb may be interdigitated for capacitance reduction. The amorphous Si:H film may be replaced by an amorphous Si:Ge:H film in which up to 40 percent of the amorphous material is Ge. Two dimensional arrays may be used in X-ray imaging, CT scanning, crystallography, high energy physics beam tracking, nuclear medicine cameras and autoradiography.

Street, Robert A. (Palo Alto, CA); Kaplan, Selig N. (El Cerrito, CA); Perez-Mendez, Victor (Berkeley, CA)

1992-01-01T23:59:59.000Z

137

High resolution amorphous silicon radiation detectors  

DOE Patents [OSTI]

A radiation detector employing amorphous Si:H cells in an array with each detector cell having at least three contiguous layers (n-type, intrinsic, p-type), positioned between two electrodes to which a bias voltage is applied. An energy conversion layer atop the silicon cells intercepts incident radiation and converts radiation energy to light energy of a wavelength to which the silicon cells are responsive. A read-out device, positioned proximate to each detector element in an array allows each such element to be interrogated independently to determine whether radiation has been detected in that cell. The energy conversion material may be a layer of luminescent material having a columnar structure. In one embodiment a column of luminescent material detects the passage therethrough of radiation to be detected and directs a light beam signal to an adjacent a-Si:H film so that detection may be confined to one or more such cells in the array. One or both electrodes may have a comb structure, and the teeth of each electrode comb may be interdigitated for capacitance reduction. The amorphous Si:H film may be replaced by an amorphous Si:Ge:H film in which up to 40 percent of the amorphous material is Ge. Two dimensional arrays may be used in X-ray imaging, CT scanning, crystallography, high energy physics beam tracking, nuclear medicine cameras and autoradiography. 18 figs.

Street, R.A.; Kaplan, S.N.; Perez-Mendez, V.

1992-05-26T23:59:59.000Z

138

Infrared optical properties of amorphous and nanocrystalline Ta{sub 2}O{sub 5} thin films  

SciTech Connect (OSTI)

The optical constants of tantalum pentoxide (Ta{sub 2}O{sub 5}) are determined in a broad spectral region from the visible to the far infrared. Ta{sub 2}O{sub 5} films of various thicknesses from approximately 170 to 1600 nm are deposited using reactive magnetron sputtering on Si substrates. X-ray diffraction shows that the as-deposited films are amorphous, and annealing in air at 800 °C results in the formation of nanocrystalline Ta{sub 2}O{sub 5}. Ellipsometry is used to obtain the dispersion in the visible and near-infrared. Two Fourier-transform infrared spectrometers are used to measure the transmittance and reflectance at wavelengths from 1 to 1000 ?m. The surface topography and microstructure of the samples are examined using atomic force microscopy, confocal microscopy, and scanning electron microscopy. Classical Lorentz oscillators are employed to model the absorption bands due to phonons and impurities. A simple model is introduced to account for light scattering in the annealed films, which contain micro-cracks. For the unannealed samples, an effective-medium approximation is used to take into account the adsorbed moisture in the film and a Drude free-electron term is also added to model the broad background absorption.

Bright, T. J.; Watjen, J. I.; Zhang, Z. M. [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)] [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Muratore, C. [Nanoelectronic Materials Branch, Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright Patterson AFB, Ohio 45433 (United States) [Nanoelectronic Materials Branch, Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright Patterson AFB, Ohio 45433 (United States); Department of Chemical and Materials Engineering, University of Dayton, Dayton, Ohio 45469 (United States); Voevodin, A. A. [Nanoelectronic Materials Branch, Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright Patterson AFB, Ohio 45433 (United States)] [Nanoelectronic Materials Branch, Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright Patterson AFB, Ohio 45433 (United States); Koukis, D. I.; Tanner, D. B. [Department of Physics, University of Florida, Gainesville, Florida 32611 (United States)] [Department of Physics, University of Florida, Gainesville, Florida 32611 (United States); Arenas, D. J. [Department of Physics, University of North Florida, Jacksonville, Florida 32254 (United States)] [Department of Physics, University of North Florida, Jacksonville, Florida 32254 (United States)

2013-08-28T23:59:59.000Z

139

APPLIED PHYSICS REVIEWS Erbium implanted thin film photonic materials  

E-Print Network [OSTI]

, phosphosilicate, borosilicate, and soda-lime glasses , ceramic thin films Al2O3, Y2O3, LiNbO3 , and amorphous. Phosphosilicate glass. . . . . . . . . . . . . . . . . . . . . . 7 C. Soda-lime silicate glass Er-doped thin film photonic materials is described. It focuses on oxide glasses pure SiO2

Polman, Albert

140

ThinFilms  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Thin Films Thin Films Manufacturing Technologies The Thin Film laboratory provides a variety of vapor deposition processes and facilities for cooperative research and development. Available capabilities include electron beam evaporation, sputter deposition, reactive deposi- tion processes, atomic layer deposition (ALD) and specialized techniques such as focused ion beam induced chemical vapor deposition. Equipment can be reconfigured for prototyping, or it can be dedicated to long-term research, development and manufacturing. Most sputter and evaporative deposition systems are capable of depositing multiple materials. Deposition capabilities and expertise * Deposition of a large variety of thin film mate- rials * Multiple sputter deposition systems - Capable of depositing four materials in a

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Effect of Au, Ag and Cu thin films' thickness on the electrical parameters of metal-porous silicon direct hydrogen fuel cell  

Science Journals Connector (OSTI)

Abstract The effect of the thickness of the gold, silver and cupper films on the electrical properties such as open circuit voltage (Voc) and short circuit current (Isc), in the direct hydrogen fuel cell, which uses water as a source of hydrogen, is studied by fabricating Metal/Porous Silicon/n-Silicon/Indium structures. The Porous Silicon (PS) layer on n-type (111) oriented silicon wafers were prepared by anodization. The thin films of Au or Ag or Cu with different thicknesses between 120 and 600 nm were deposited onto the PS surface by the electron-beam technique. The obtained results indicated that Voc and Isc, strongly depend on the Au, Ag and Cu layer thicknesses. The Au/PS/n-Si structure generated highest Voc and Isc values for all thicknesses of Au film. The best values of Voc and Isc were obtained at 325 nm as 0.89 V and 0.021 mA for Au, at 350 nm as 0.75 V and 0.017 mA for Ag, at 350 nm as 0.50 V and 0.010 mA, respectively.

Cigdem Oruc; Sevinc Guler

2014-01-01T23:59:59.000Z

142

Effect of deposition temperature on electron-beam evaporated polycrystalline silicon thin-film and crystallized by diode laser  

SciTech Connect (OSTI)

The effects of the deposition temperature on the microstructure, crystallographic orientation, and electrical properties of a 10-?m thick evaporated Si thin-film deposited on glass and crystallized using a diode laser, are investigated. The crystallization of the Si thin-film is initiated at a deposition temperature between 450 and 550?°C, and the predominant (110) orientation in the normal direction is found. Pole figure maps confirm that all films have a fiber texture and that it becomes stronger with increasing deposition temperature. Diode laser crystallization is performed, resulting in the formation of lateral grains along the laser scan direction. The laser power required to form lateral grains is higher in case of films deposited below 450?°C for all scan speeds. Pole figure maps show 75% occupancies of the (110) orientation in the normal direction when the laser crystallized film is deposited above 550?°C. A higher density of grain boundaries is obtained when the laser crystallized film is deposited below 450?°C, which limits the solar cell performance by n?=?2 recombination, and a performance degradation is expected due to severe shunting.

Yun, J., E-mail: j.yun@unsw.edu.au; Varalmov, S.; Huang, J.; Green, M. A. [School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney, New South Wales 2052 (Australia); Kim, K. [School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Sydney, New South Wales 2052 (Australia); Suntech R and D Australia, Botany, New South Wales 2019 (Australia)

2014-06-16T23:59:59.000Z

143

Abstract--In this paper, the propagation characteristics of an enhanced-thickness magnetic nanoparticle thin film are  

E-Print Network [OSTI]

nanoparticle thin film are investigated on high resistivity silicon substrate (10,000 ohm-cm) for the first time up to 60 GHz. Contrary to other thin films, this nanoparticle thin film can achieve a thickness up. Index Terms-- Magnetic thin film, Nanoparticle, Coplanar waveguide, high-permeability materials, FGC I

Tentzeris, Manos

144

Three dimensional amorphous silicon/microcrystalline silicon solar cells  

DOE Patents [OSTI]

Three dimensional deep contact amorphous silicon/microcrystalline silicon (a-Si/{micro}c-Si) solar cells are disclosed which use deep (high aspect ratio) p and n contacts to create high electric fields within the carrier collection volume material of the cell. The deep contacts are fabricated using repetitive pulsed laser doping so as to create the high aspect p and n contacts. By the provision of the deep contacts which penetrate the electric field deep into the material where the high strength of the field can collect many of the carriers, thereby resulting in a high efficiency solar cell. 4 figs.

Kaschmitter, J.L.

1996-07-23T23:59:59.000Z

145

Hydrogenated amorphous silicon-germanium alloys  

SciTech Connect (OSTI)

This report describes the effects of the germanium fraction in hydrogenated amorphous silicon-germanium alloys on various parameters, especially those that are indicators of film quality, and the impact of deposition methods, feedgas mixtures, and other deposition parameters on a SiGe:H and a-SiGe:H:F film characteristics and quality. Literature data show the relationship between germanium content, hydrogen content, deposition method (various glow discharges and CVD), feedgas lmixture, and other parameters and properties, such as optical band gap, dark and photoconductivities, photosensitivity, activation energy, Urbach parameter, and spin density. Some of these are convenient quality indicators; another is the absence of microstructure. Examining RF glow discharge with both a diode and triode geometry, DC proximity glow discharge, microwave glow discharge, and photo-CVD, using gas mixtures such as hydrogen-diluted and undiluted mixtures of silane/germane, disilane/germane, silane/germaniumtetrafluoride, and others, it was observed that hydrogen dilution (or inert gas dilution) is essential in achieving high photosensitivity in silicon-germanium alloys (in contradistinction to amorphous hydrogenated silicon). Hydrogen dilution results in a higher photosensitivity than do undiluted gas mixtures. 81 refs., 42 figs., 7 tabs.

Luft, W.

1988-02-01T23:59:59.000Z

146

Generation of low work function, stable compound thin films by laser ablation  

DOE Patents [OSTI]

Generation of low work function, stable compound thin films by laser ablation. Compound thin films with low work function can be synthesized by simultaneously laser ablating silicon, for example, and thermal evaporating an alkali metal into an oxygen environment. For example, the compound thin film may be composed of Si/Cs/O. The work functions of the thin films can be varied by changing the silicon/alkali metal/oxygen ratio. Low work functions of the compound thin films deposited on silicon substrates were confirmed by ultraviolet photoelectron spectroscopy (UPS). The compound thin films are stable up to 500.degree. C. as measured by x-ray photoelectron spectroscopy (XPS). Tests have established that for certain chemical compositions and annealing temperatures of the compound thin films, negative electron affinity (NEA) was detected. The low work function, stable compound thin films can be utilized in solar cells, field emission flat panel displays, electron guns, and cold cathode electron guns.

Dinh, Long N. (Concord, CA); McLean, II, William (Oakland, CA); Balooch, Mehdi (Berkeley, CA); Fehring, Jr., Edward J. (Dublin, CA); Schildbach, Marcus A. (Livermore, CA)

2001-01-01T23:59:59.000Z

147

Antimony Induced Crystallization of Amorphous Silicon  

Science Journals Connector (OSTI)

Antimony induced crystallization of PVD (physics vapor deposition) amorphous silicon can be observed on sapphire substrates. Very large crystalline regions up to several tens of micrometers can be formed. The Si diffraction patterns of the area of crystallization can be observed with TEM (transmission electron microscopy). Only a few and much smaller crystals of the order of 1?m were formed when the antimony layer was deposited by MBE (molecular beam epitaxy) compared with a layer formed by thermal evaporation. The use of high vacuum is essential in order to observe any Sb induced crystallization at all. In addition it is necessary to take measures to limit the evaporation of the antimony.

Y. Wang; H.Z. Li; C.N. Yu; G.M. Wu; I. Gordon; P. Schattschneider; O. Van Der Biest

2007-01-01T23:59:59.000Z

148

Subtleties of capacitance transients in amorphous silicon  

SciTech Connect (OSTI)

Using junction capacitance methods, the authors describe the effect of contacts on charge emission transients in n-type hydrogenated amorphous silicon. The results demonstrate some of the difficulties encountered in observing and interpreting anomalous temperature independent emission transients (slow relaxation). In this paper, the authors present additional data and reconcile the absence of anomalous emission transients in some cases with a discussion of the dynamics of depletion width filling. The authors show that the transient capacitance response of Schottky structure is not only related to the contact configuration but is connected to the rate of charge injection into the depletion region.

Crandall, R.S. [National Renewable Energy Lab., Golden, CO (United States); Lips, K. [Hahn-Meitner-Inst., Berlin (Germany)

1996-12-31T23:59:59.000Z

149

E-Print Network 3.0 - amorphous silicon solar Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

for a research organization in the optimization of the amorphous silicon solar cell... photovoltaics on flexible substrates. Managed amorphous silicon research program...

150

Structural relaxation of vacancies in amorphous silicon  

SciTech Connect (OSTI)

The authors have studied the structural relaxation of vacancies in amorphous silicon (a-Si) using a tight-binding molecular-dynamics method. The most significant difference between vacancies in a-Si and those in crystalline silicon (c-Si) is that the deep gap states do not show up in a-Si. This difference is explained through the unusual behavior of the structural relaxation near the vacancies in a-Si, which enhances the sp{sup 2} + p bonding near the band edges. They have also observed that the vacancies do not migrate below 450 K although some of them can still be annihilated, particularly at high defect density due to large structural relaxation.

Kim, E.; Lee, Y.H.; Chen, C.; Pang, T.

1997-07-01T23:59:59.000Z

151

Superlattice doped layers for amorphous silicon photovoltaic cells  

DOE Patents [OSTI]

Superlattice doped layers for amorphous silicon photovoltaic cells comprise a plurality of first and second lattices of amorphous silicon alternatingly formed on one another. Each of the first lattices has a first optical bandgap and each of the second lattices has a second optical bandgap different from the first optical bandgap. A method of fabricating the superlattice doped layers also is disclosed.

Arya, Rajeewa R. (Doylestown, PA)

1988-01-12T23:59:59.000Z

152

Hydrogen plasma enhanced crystallization of hydrogenated amorphous silicon films  

E-Print Network [OSTI]

Hydrogen plasma enhanced crystallization of hydrogenated amorphous silicon films K. Pangal,a) J. C August 1998; accepted for publication 21 October 1998 We report that a room temperature hydrogen plasma thermal crystallization of amorphous silicon time by a factor of five. Exposure to hydrogen plasma reduces

153

Thin film hydrogen sensor  

DOE Patents [OSTI]

A thin film hydrogen sensor includes a substantially flat ceramic substrate with first and second planar sides and a first substrate end opposite a second substrate end; a thin film temperature responsive resistor on the first planar side of the substrate proximate to the first substrate end; a thin film hydrogen responsive metal resistor on the first planar side of the substrate proximate to the fist substrate end and proximate to the temperature responsive resistor; and a heater on the second planar side of the substrate proximate to the first end. 5 figs.

Cheng, Y.T.; Poli, A.A.; Meltser, M.A.

1999-03-23T23:59:59.000Z

154

Thin film hydrogen sensor  

DOE Patents [OSTI]

A thin film hydrogen sensor, includes: a substantially flat ceramic substrate with first and second planar sides and a first substrate end opposite a second substrate end; a thin film temperature responsive resistor on the first planar side of the substrate proximate to the first substrate end; a thin film hydrogen responsive metal resistor on the first planar side of the substrate proximate to the fist substrate end and proximate to the temperature responsive resistor; and a heater on the second planar side of the substrate proximate to the first end.

Cheng, Yang-Tse (Rochester Hills, MI); Poli, Andrea A. (Livonia, MI); Meltser, Mark Alexander (Pittsford, NY)

1999-01-01T23:59:59.000Z

155

An infrared and luminescence study of tritiated amorphous silicon  

SciTech Connect (OSTI)

Tritium has been incorporated into amorphous silicon. Infrared spectroscopy shows new infrared vibration modes due to silicon-tritium (Si-T) bonds in the amorphous silicon network. Si-T vibration frequencies are related to Si-H vibration frequencies by simple mass relationships. Inelastic collisions of {beta} particles, produced as a result of tritium decay, with the amorphous silicon network results in the generation of electron-hole pairs. Radiative recombination of these carriers is observed. Dangling bonds associated with the tritium decay reduce luminescence efficiency.

Sidhu, L.S.; Kosteski, T.; Kherani, N.P.; Gaspari, F.; Zukotynski, S.; Shmayda, W.

1997-07-01T23:59:59.000Z

156

Thin Film Photovoltaics Research  

Broader source: Energy.gov [DOE]

The U.S. Department of Energy (DOE) supports research and development of four thin-film technologies on the path to achieving cost-competitive solar energy, including:

157

Disorder improves nanophotonic light trapping in thin-film solar cells  

SciTech Connect (OSTI)

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.

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)

2014-03-31T23:59:59.000Z

158

Black Silicon Solar Thin-film Microcells Integrating Top Nanocone Structures for Broadband and Omnidirectional Light-Trapping  

E-Print Network [OSTI]

Recently developed classes of monocrystalline silicon solar microcells (u-cell) can be assembled into modules with characteristics (i.e., mechanically flexible forms, compact concentrator designs, and high-voltage outputs) that would be impossible to achieve using conventional, wafer-based approaches. In this paper, we describe a highly dense, uniform and non-periodic nanocone forest structure of black silicon (bSi) created on optically-thin (30 um) u-cells for broadband and omnidirectional light-trapping with a lithography-free and high-throughput plasma texturizing process. With optimized plasma etching conditions and a silicon nitride passivation layer, black silicon u-cells, when embedded in a polymer waveguiding layer, display dramatic increases of as much as 65.7% in short circuit current, as compared to a bare silicon device. The conversion efficiency increases from 8% to 11.5% with a small drop in open circuit voltage and fill factor.

Xu, Zhida; Brueckner, Eric P; Li, Lanfang; Jiang, Jing; Nuzzo, Ralph G; Liu, Gang L

2014-01-01T23:59:59.000Z

159

RF Sputtering for preparing substantially pure amorphous silicon monohydride  

DOE Patents [OSTI]

A process for controlling the dihydride and monohydride bond densities in hydrogenated amorphous silicon produced by reactive rf sputtering of an amorphous silicon target. There is provided a chamber with an amorphous silicon target and a substrate therein with the substrate and the target positioned such that when rf power is applied to the target the substrate is in contact with the sputtering plasma produced thereby. Hydrogen and argon are fed to the chamber and the pressure is reduced in the chamber to a value sufficient to maintain a sputtering plasma therein, and then rf power is applied to the silicon target to provide a power density in the range of from about 7 watts per square inch to about 22 watts per square inch to sputter an amorphous silicon hydride onto the substrate, the dihydride bond density decreasing with an increase in the rf power density. Substantially pure monohydride films may be produced.

Jeffrey, Frank R. (Ames, IA); Shanks, Howard R. (Ames, IA)

1982-10-12T23:59:59.000Z

160

Process for producing amorphous and crystalline silicon nitride  

DOE Patents [OSTI]

A process for producing amorphous or crystalline silicon nitride is disclosed which comprises reacting silicon disulfide ammonia gas at elevated temperature. In a preferred embodiment silicon disulfide in the form of "whiskers" or needles is heated at temperature ranging from about 900.degree. C. to about 1200.degree. C. to produce silicon nitride which retains the whisker or needle morphological characteristics of the silicon disulfide. Silicon carbide, e.g. in the form of whiskers, also can be prepared by reacting substituted ammonia, e.g. methylamine, or a hydrocarbon containing active hydrogen-containing groups, such as ethylene, with silicon disulfide, at elevated temperature, e.g. 900.degree. C.

Morgan, Peter E. D. (Thousand Oaks, CA); Pugar, Eloise A. (Newbury Park, CA)

1985-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Plasma polymerization of C[subscript 4]F[subscript 8] thin film on high aspect ratio silicon molds  

E-Print Network [OSTI]

High aspect ratio polymeric micro-patterns are ubiquitous in many fields ranging from sensors, actuators, optics, fluidics and medical. Second generation PDMS molds are replicated against first generation silicon molds ...

Yeo, L. P.

162

Neutron reflectometry characterization of interface width between sol-gel titanium dioxide and silicon dioxide thin films  

SciTech Connect (OSTI)

Neutron reflectometry (NR) was used to directly measure the interface width between a titanium dioxide and a silicon dioxide film deposited by sol-gel processing. In a bilayer heated to 450 C, NR measurements showed that the interface width is 0.8 nm. This width is the same as the roughness of a sol-gel silicon dioxide surface after the same heat treatment, suggesting no interdiffusion or mixing at the bilayer interface.

Keddie, J.L.; Norton, L.J.; Kramer, E.J.; Giannelis, E.P. (Cornell Univ., Ithaca, NY (United States). Dept. of Materials Science and Engineering)

1993-10-01T23:59:59.000Z

163

Accounting for Localized Defects in the Optoelectronic Design of Thin-Film Solar Cells  

E-Print Network [OSTI]

Thin-film silicon solar cell technology," Progress insolar cells: modeling, materials and device technology.technologies competitive with traditional wafer based solar cells,

Deceglie, Michael G.

2014-01-01T23:59:59.000Z

164

Photoluminescence properties and crystallization of silicon quantum dots in hydrogenated amorphous Si-rich silicon carbide films  

SciTech Connect (OSTI)

Silicon quantum dots (QDs) embedded in hydrogenated amorphous Si-rich silicon carbide (?-SiC:H) thin films were realized by plasma-enhanced chemical vapor deposition process and post-annealing. Fluorescence spectroscopy was used to characterize the room-temperature photoluminescence properties. X-ray photoelectron spectroscopy was used to analyze the element compositions and bonding configurations. Ultraviolet visible spectroscopy, Raman scattering, and high-resolution transmission electron microscopy were used to display the microstructural properties. Photoluminescence measurements reveal that there are six emission sub-bands, which behave in different ways. The peak wavelengths of sub-bands P1, P2, P3, and P6 are pinned at about 425.0, 437.3, 465.0, and 591.0?nm, respectively. Other two sub-bands, P4 is red-shifted from 494.6 to 512.4?nm and P5 from 570.2 to 587.8?nm with temperature increasing from 600 to 900?°C. But then are both blue-shifted, P4 to 500.2?nm and P5 to 573.8?nm from 900 to 1200?°C. The X-ray photoelectron spectroscopy analysis shows that the samples are in Si-rich nature, Si-O and Si-N bonds consumed some silicon atoms. The structure characterization displays that a separation between silicon phase and SiC phase happened; amorphous and crystalline silicon QDs synthesized with increasing the annealing temperature. P1, P2, P3, and P6 sub-bands are explained in terms of defect-related emission, while P4 and P5 sub-bands are explained in terms of quantum confinement effect. A correlation between the peak wavelength shift, as well as the integral intensity of the spectrum and crystallization of silicon QDs is supposed. These results help clarify the probable luminescence mechanisms and provide the possibility to optimize the optical properties of silicon QDs in Si-rich ?-SiC: H materials.

Wen, Guozhi [School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); School of Electronic and Electrical Engineering, Wuhan Polytechnic University, Wuhan, Hubei 430023 (China); Zeng, Xiangbin, E-mail: eexbzeng@mail.hust.edu.cn; Wen, Xixin; Liao, Wugang [School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)

2014-04-28T23:59:59.000Z

165

Amorphous silicon passivated contacts for diffused junction silicon solar cells  

Science Journals Connector (OSTI)

Carrier recombination at the metal contacts is a major obstacle in the development of high-performance crystalline silicon homojunction solar cells. To address this issue we insert thin intrinsic hydrogenated amorphous silicon [a-Si:H(i)] passivating films between the dopant-diffused silicon surface and aluminum contacts. We find that with increasing a-Si:H(i) interlayer thickness (from 0 to 16?nm) the recombination loss at metal-contacted phosphorus (n+) and boron (p+) diffused surfaces decreases by factors of ?25 and ?10 respectively. Conversely the contact resistivity increases in both cases before saturating to still acceptable values of ? 50 m? cm2 for n+ and ?100 m? cm2 for p+ surfaces. Carrier transport towards the contacts likely occurs by a combination of carrier tunneling and aluminum spiking through the a-Si:H(i) layer as supported by scanning transmission electron microscopy–energy dispersive x-ray maps. We explain the superior contact selectivity obtained on n+ surfaces by more favorable band offsets and capture cross section ratios of recombination centers at the c-Si/a-Si:H(i) interface.

J. Bullock; A. Cuevas

2014-01-01T23:59:59.000Z

166

Amorphous silicon passivated contacts for diffused junction silicon solar cells  

SciTech Connect (OSTI)

Carrier recombination at the metal contacts is a major obstacle in the development of high-performance crystalline silicon homojunction solar cells. To address this issue, we insert thin intrinsic hydrogenated amorphous silicon [a-Si:H(i)] passivating films between the dopant-diffused silicon surface and aluminum contacts. We find that with increasing a-Si:H(i) interlayer thickness (from 0 to 16?nm) the recombination loss at metal-contacted phosphorus (n{sup +}) and boron (p{sup +}) diffused surfaces decreases by factors of ?25 and ?10, respectively. Conversely, the contact resistivity increases in both cases before saturating to still acceptable values of ? 50 m? cm{sup 2} for n{sup +} and ?100 m? cm{sup 2} for p{sup +} surfaces. Carrier transport towards the contacts likely occurs by a combination of carrier tunneling and aluminum spiking through the a-Si:H(i) layer, as supported by scanning transmission electron microscopy–energy dispersive x-ray maps. We explain the superior contact selectivity obtained on n{sup +} surfaces by more favorable band offsets and capture cross section ratios of recombination centers at the c-Si/a-Si:H(i) interface.

Bullock, J., E-mail: james.bullock@anu.edu.au; Yan, D.; Wan, Y.; Cuevas, A. [Research School of Engineering, The Australian National University, Canberra, ACT 0200 (Australia); Demaurex, B.; Hessler-Wyser, A.; De Wolf, S. [École Polytechnique Fédérale de Lausanne (EPFL), Institute of micro engineering (IMT), Photovoltaics and Thin Film Electronic Laboratory, Maladière 71, CH-200 Neuchâtel (Switzerland)

2014-04-28T23:59:59.000Z

167

Low temperature grown polycrystalline La{sub 0.7}Sr{sub 0.3}MnO{sub 3} thin films on amorphous SiO{sub 2} substrates by rf magnetron sputtering  

SciTech Connect (OSTI)

The La{sub 0.7}Sr{sub 0.3}MnO{sub 3} thin films have been prepared on amorphous SiO{sub 2} substrates by a rf magnetron sputtering technique under various oxygen flow rates and rf powers at a relatively low substrate temperature of 350 deg. C. The effects of oxygen flow rate and rf power on their physical properties were systematically investigated. X-ray diffraction results show that the growth orientation and crystallinity of the films were affected by rf power and oxygen flow rate. The electrical resistivity of the films was reduced with increasing oxygen flow rate and rf power due to enhanced {l_brace}100{r_brace} growth plane orientation and enlarged grain size of the films. In addition, a relatively high temperature coefficient of resistance value of -2.4% was obtained in the present investigation even with low deposition temperature.

Choi, Sun Gyu; Sivasankar Reddy, A.; Park, Hyung-Ho; Yang, Woo Seok; Ryu, Hojun; Yu, Byoung-Gon [Department of Materials Science and Engineering, Yonsei University, 134 Sinchon-dong, Seodaemun-ku, Seoul 120-749 (Korea, Republic of); Electronics and Telecommunications Research Institute, Daejeon 305-700 (Korea, Republic of)

2009-07-15T23:59:59.000Z

168

NMR characterization of thin films  

DOE Patents [OSTI]

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.

Gerald, II, Rex E. (Brookfield, IL); Klingler, Robert J. (Glenview, IL); Rathke, Jerome W. (Homer Glen, IL); Diaz, Rocio (Chicago, IL); Vukovic, Lela (Westchester, IL)

2008-11-25T23:59:59.000Z

169

Thin film photovoltaic cell  

DOE Patents [OSTI]

A thin film photovoltaic cell having a transparent electrical contact and an opaque electrical contact with a pair of semiconductors therebetween includes utilizing one of the electrical contacts as a substrate and wherein the inner surface thereof is modified by microroughening while being macro-planar.

Meakin, John D. (Newark, DE); Bragagnolo, Julio (Newark, DE)

1982-01-01T23:59:59.000Z

170

Nuclear magnetic resonance studies of hydrogen in amorphous silicon  

SciTech Connect (OSTI)

Proton and deuteron NMR in hydrogenated amorphous silicon yield quantitative measures of species-specific structural configurations and their dynamics. Populations of silicon-bonded and molecular hydrogens correlate with photovoltaic quality, doping, illumination/dark anneal sequences, and with infrared and other characterizations. High quality films contain substantial populations of nanovoid-trapped molecular hydrogen.

Norberg, R.E.; Fedders, P.A.; Leopold, D.J. [Washington Univ., St. Louis, MO (United States). Dept. of Physics

1996-12-31T23:59:59.000Z

171

E-Print Network 3.0 - amorphous silicon-carbon alloys Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

1. On the one hand, stable amorphous alloy which leads to the change... of eutectic alloy amorphous silicon film. (b) SAD pattern of ... Source: Grigoriev, Alexei -...

172

A thin film transistor driven microchannel device  

E-Print Network [OSTI]

= [8] 25 where n = 4 for the ideal case. However, based on experimental results, typical values for n are between 1 and 2.22 In any case, the larger potential drop appears at the smaller electrode. 2.4. PECVD Thin Film Silicon nitride film... can be deposited by a low-pressure chemical vapor deposition (LPCVD) and plasma enhanced chemical vapor deposition (PECVD). Table II shows a comparison of silicon nitride?s physical properties between two deposition methods. The PECVD silicon...

Lee, Hyun Ho

2005-02-17T23:59:59.000Z

173

Hydrogenated amorphous silicon films produced by chemical vapor deposition: Final report  

SciTech Connect (OSTI)

Hydrogenated amorphous silicon (a-Si:H) is a technologically important semiconductor, well-suited for solar photovoltaic energy conversion and thin film device applications. While the glow discharge technique is widely used for the deposition of a-Si:H films, this work is focused on the use of the chemical vapor deposition (CVD) technique, i.e., the thermal decomposition of disilane and higher silanes, for the deposition of a-Si:H films. A simple technique for the preparation of disilane and higher silanes by using an electric discharge in monosilane under atmospheric pressure has been developed, and the discharge product can be used directly for the deposition process. The important parameters of the CVD process including the substrate temperature, the composition and flow rate of the reaction mixture, and the nature of the diluent gas for disilane, have also been investigated. The deposition rate of a-Si:H films in a helium atmosphere is considerably higher than that in a hydrogen atmosphere, and the CVD process in a helium atmosphere is well-suited for the deposition of thick a-Si:H films. The a-Si:H films deposited under various conditions have been characterized by the photoconductivity, dissolution rate, optical absorption, mechanical stress, gap state density, minority carrier diffusion length, and stability measurements. On the basis of these measurements, a-Si:H films deposited by the thermal decomposition of disilane in a helium atmosphere exhibit better structural and electronic properties than those deposited in a hydrogen atmosphere.

Not Available

1987-04-01T23:59:59.000Z

174

Effective interface state effects in hydrogenated amorphous-crystalline silicon heterostructures using ultraviolet laser photocarrier radiometry  

SciTech Connect (OSTI)

Ultraviolet photocarrier radiometry (UV-PCR) was used for the characterization of thin-film (nanolayer) intrinsic hydrogenated amorphous silicon (i-a-Si:H) on c-Si. The small absorption depth (approximately 10?nm at 355?nm laser excitation) leads to strong influence of the nanolayer parameters on the propagation and recombination of the photocarrier density wave (CDW) within the layer and the substrate. A theoretical PCR model including the presence of effective interface carrier traps was developed and used to evaluate the transport parameters of the substrate c-Si as well as those of the i-a-Si:H nanolayer. Unlike conventional optoelectronic characterization methods such as photoconductance, photovoltage, and photoluminescence, UV-PCR can be applied to more complete quantitative characterization of a-Si:H/c-Si heterojunction solar cells, including transport properties and defect structures. The quantitative results elucidate the strong effect of a front-surface passivating nanolayer on the transport properties of the entire structure as the result of effective a-Si:H/c-Si interface trap neutralization through occupation. A further dramatic improvement of those properties with the addition of a back-surface passivating nanolayer is observed and interpreted as the result of the interaction of the increased excess bulk CDW with, and more complete occupation and neutralization of, effective front interface traps.

Melnikov, A. [Center for Advanced Diffusion-Wave Technologies (CADIFT), Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8 (Canada); Mandelis, A. [Center for Advanced Diffusion-Wave Technologies (CADIFT), Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8 (Canada); Electrical and Computer Engineering, University of Toronto, Toronto, Ontario M5S 3G4 (Canada); Halliop, B.; Kherani, N. P. [Electrical and Computer Engineering, University of Toronto, Toronto, Ontario M5S 3G4 (Canada)

2013-12-28T23:59:59.000Z

175

Active pixel imagers incorporating pixel-level amplifiers based on polycrystalline-silicon thin-film transistors  

SciTech Connect (OSTI)

Active matrix, flat-panel imagers (AMFPIs) employing a 2D matrix of a-Si addressing TFTs have become ubiquitous in many x-ray imaging applications due to their numerous advantages. However, under conditions of low exposures and/or high spatial resolution, their signal-to-noise performance is constrained by the modest system gain relative to the electronic additive noise. In this article, a strategy for overcoming this limitation through the incorporation of in-pixel amplification circuits, referred to as active pixel (AP) architectures, using polycrystalline-silicon (poly-Si) TFTs is reported. Compared to a-Si, poly-Si offers substantially higher mobilities, enabling higher TFT currents and the possibility of sophisticated AP designs based on both n- and p-channel TFTs. Three prototype indirect detection arrays employing poly-Si TFTs and a continuous a-Si photodiode structure were characterized. The prototypes consist of an array (PSI-1) that employs a pixel architecture with a single TFT, as well as two arrays (PSI-2 and PSI-3) that employ AP architectures based on three and five TFTs, respectively. While PSI-1 serves as a reference with a design similar to that of conventional AMFPI arrays, PSI-2 and PSI-3 incorporate additional in-pixel amplification circuitry. Compared to PSI-1, results of x-ray sensitivity demonstrate signal gains of {approx}10.7 and 20.9 for PSI-2 and PSI-3, respectively. These values are in reasonable agreement with design expectations, demonstrating that poly-Si AP circuits can be tailored to provide a desired level of signal gain. PSI-2 exhibits the same high levels of charge trapping as those observed for PSI-1 and other conventional arrays employing a continuous photodiode structure. For PSI-3, charge trapping was found to be significantly lower and largely independent of the bias voltage applied across the photodiode. MTF results indicate that the use of a continuous photodiode structure in PSI-1, PSI-2, and PSI-3 results in optical fill factors that are close to unity. In addition, the greater complexity of PSI-2 and PSI-3 pixel circuits, compared to that of PSI-1, has no observable effect on spatial resolution. Both PSI-2 and PSI-3 exhibit high levels of additive noise, resulting in no net improvement in the signal-to-noise performance of these early prototypes compared to conventional AMFPIs. However, faster readout rates, coupled with implementation of multiple sampling protocols allowed by the nondestructive nature of pixel readout, resulted in a significantly lower noise level of {approx}560 e (rms) for PSI-3.

El-Mohri, Youcef; Antonuk, Larry E.; Koniczek, Martin; Zhao Qihua; Li Yixin; Street, Robert A.; Lu Jengping [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan 48109 (United States); Palo Alto Research Center (PARC), 3333 Coyote Hill Road, Palo Alto, California 94304 (United States)

2009-07-15T23:59:59.000Z

176

Radiation damage to amorphous carbon thin films irradiated by multiple 46.9 nm laser shots below the single-shot damage threshold  

SciTech Connect (OSTI)

High-surface-quality amorphous carbon (a-C) optical coatings with a thickness of 45 nm, deposited by magnetron sputtering on a silicon substrate, were irradiated by the focused beam of capillary-discharge Ne-like Ar extreme ultraviolet laser (CDL=capillary-discharge laser; XUV=extreme ultraviolet, i.e., wavelengths below 100 nm). The laser wavelength and pulse duration were 46.9 nm and 1.7 ns, respectively. The laser beam was focused onto the sample surface by a spherical Sc/Si multilayer mirror with a total reflectivity of about 30%. The laser pulse energy was varied from 0.4 to 40 muJ on the sample surface. The irradiation was carried out at five fluence levels between 0.1 and 10 J/cm{sup 2}, accumulating five different series of shots, i.e., 1, 5, 10, 20, and 40. The damage to the a-C thin layer was investigated by atomic force microscopy (AFM) and Nomarski differential interference contrast (DIC) optical microscopy. The dependence of the single-shot-damaged area on pulse energy makes it possible to determine a beam spot diameter in the focus. Its value was found to be equal to 23.3+-3.0 mum using AFM data, assuming the beam to have a Gaussian profile. Such a plot can also be used for a determination of single-shot damage threshold in a-C. A single-shot threshold value of 1.1 J/cm{sup 2} was found. Investigating the consequences of the multiple-shot exposure, it has been found that an accumulation of 10, 20, and 40 shots at a fluence of 0.5 J/cm{sup 2}, i.e., below the single-shot damage threshold, causes irreversible changes of thin a-C layers, which can be registered by both the AFM and the DIC microscopy. In the center of the damaged area, AFM shows a-C removal to a maximum depth of 0.3, 1.2, and 1.5 nm for 10-, 20- and 40-shot exposure, respectively. Raman microprobe analysis does not indicate any change in the structure of the remaining a-C material. The erosive behavior reported here contrasts with the material expansion observed earlier [L. Juha et al., Proc. SPIE 5917, 91 (2005)] on an a-C sample irradiated by a large number of femtosecond pulses of XUV high-order harmonics.

Juha, L.; Hajkova, V.; Vorlicek, V. [Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8 (Czech Republic); Chalupsky, J. [Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8 (Czech Republic); Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Brehova 7, 115 19 Prague 1 (Czech Republic); Ritucci, A.; Reale, A.; Zuppella, P. [Department of Physics, University of L'Aquila, gc Laboratorio Nazionale del Gran Sasso (Istituto Nazionale di Fisica Nucleare-INFN), 67010 Coppito, L'Aquila (Italy); Stoermer, M. [GKSS Research Center, Max-Planck-Strasse 1, D-21502 Geesthacht (Germany)

2009-05-01T23:59:59.000Z

177

E-Print Network 3.0 - amorphous silicon germanium Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

6 September 2007; published online 17 October 2007 Amorphous silicon... -fiber optoelectronics.5,6 We have shown that crystalline silicon and ... Source: Gopalan, Venkatraman -...

178

E-Print Network 3.0 - amorphous-silicon-based solar cell Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Vol. 609 2000 Materials Research Society Preparation of Microcrystalline Silicon Based Solar Cells at High i-layer Summary: light exposure as do the amorphous silicon-based...

179

Modeling and control of thin film surface morphology: application to thin film solar cells  

E-Print Network [OSTI]

materials, thin film solar cell technology stands to benefitThin-film solar cells: Review of materials, technologies and

Huang, Jianqiao

2012-01-01T23:59:59.000Z

180

Transmissive metallic contact for amorphous silicon solar cells  

DOE Patents [OSTI]

A transmissive metallic contact for amorphous silicon semiconductors includes a thin layer of metal, such as aluminum or other low work function metal, coated on the amorphous silicon with an antireflective layer coated on the metal. A transparent substrate, such as glass, is positioned on the light reflective layer. The metallic layer is preferably thin enough to transmit at least 50% of light incident thereon, yet thick enough to conduct electricity. The antireflection layer is preferably a transparent material that has a refractive index in the range of 1.8 to 2.2 and is approximately 550A to 600A thick.

Madan, A.

1984-11-29T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Improvement of pin-type amorphous silicon solar cell performance by employing double silicon-carbide p-layer structure  

E-Print Network [OSTI]

Improvement of pin-type amorphous silicon solar cell performance by employing double silicon-carbide Received 30 October 2003; accepted 18 November 2003 We investigated a double silicon-carbide p-layer structure consisting of a undiluted p-type amorphous silicon-carbide (p-a-SiC:H) window layer and a hydrogen

Kim, Yong Jung

182

Thermal rectification at silicon-amorphous polyethylene interface Ming Hu,1,a  

E-Print Network [OSTI]

Thermal rectification at silicon-amorphous polyethylene interface Ming Hu,1,a Pawel Keblinski,1,b heat currents. We estimate that in the limit of large heat currents, the silicon-amorphous polyethylene by amorphous polymer polyethylene PE and silicon crystal. We will also show that the mecha- nism governing

Li, Baowen

183

Thin film photovoltaic device  

DOE Patents [OSTI]

A thin film photovoltaic solar cell which utilizes a zinc phosphide semiconductor is of the homojunction type comprising an n-type conductivity region forming an electrical junction with a p-type region, both regions consisting essentially of the same semiconductor material. The n-type region is formed by treating zinc phosphide with an extrinsic dopant such as magnesium. The semiconductor is formed on a multilayer substrate which acts as an opaque contact. Various transparent contacts may be used, including a thin metal film of the same chemical composition as the n-type dopant or conductive oxides or metal grids. 5 figs.

Catalano, A.W.; Bhushan, M.

1982-08-03T23:59:59.000Z

184

Thin film photovoltaic device  

DOE Patents [OSTI]

A thin film photovoltaic solar cell which utilizes a zinc phosphide semiconductor is of the homojunction type comprising an n-type conductivity region forming an electrical junction with a p-type region, both regions consisting essentially of the same semiconductor material. The n-type region is formed by treating zinc phosphide with an extrinsic dopant such as magnesium. The semiconductor is formed on a multilayer substrate which acts as an opaque contact. Various transparent contacts may be used, including a thin metal film of the same chemical composition as the n-type dopant or conductive oxides or metal grids.

Catalano, Anthony W. (Wilmington, DE); Bhushan, Manjul (Wilmington, DE)

1982-01-01T23:59:59.000Z

185

Thin film hydrogen sensor  

DOE Patents [OSTI]

A hydrogen sensor element comprises an essentially inert, electrically-insulating substrate having a thin-film metallization deposited thereon which forms at least two resistors on the substrate. The metallization comprises a layer of Pd or a Pd alloy for sensing hydrogen and an underlying intermediate metal layer for providing enhanced adhesion of the metallization to the substrate. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors, and at least one of the resistors is left uncovered. The difference in electrical resistances of the covered resistor and the uncovered resistor is related to hydrogen concentration in a gas to which the sensor element is exposed.

Lauf, Robert J. (Oak Ridge, TN); Hoffheins, Barbara S. (Knoxville, TN); Fleming, Pamela H. (Oak Ridge, TN)

1994-01-01T23:59:59.000Z

186

Thin film photovoltaic device with multilayer substrate  

DOE Patents [OSTI]

A thin film photovoltaic device which utilizes at least one compound semiconductor layer chosen from Groups IIB and VA of the Periodic Table is formed on a multilayer substrate The substrate includes a lowermost support layer on which all of the other layers of the device are formed. Additionally, an uppermost carbide or silicon layer is adjacent to the semiconductor layer. Below the carbide or silicon layer is a metal layer of high conductivity and expansion coefficient equal to or slightly greater than that of the semiconductor layer.

Catalano, Anthony W. (Rushland, PA); Bhushan, Manjul (Wilmington, DE)

1984-01-01T23:59:59.000Z

187

Amorphous Silicon as Semiconductor Material for High Resolution LAPS  

E-Print Network [OSTI]

-08 3.E -08 0 200 400 600 800 displacem ent/µµµµm current/A 1000 2000 3000 4000 1000 2000 3000 4000-substrate Amorphous silicon -4 -2 0 2 4 0,2 0,4 0,6 0,8 1,0 photocurrenta.u. gate voltage/V 600µm x 600µm area scan

Moritz, Werner

188

Conducting polymer and hydrogenated amorphous silicon hybrid solar cells  

E-Print Network [OSTI]

November 2005 An organic-inorganic hybrid solar cell with a p-i-n stack structure has been investigated for their potential in electronic devices such as organic light emitting diodes OLEDs , solar cells, photode- tectorsConducting polymer and hydrogenated amorphous silicon hybrid solar cells Evan L. Williams

Schiff, Eric A.

189

Charge-Density Variation in a Model of Amorphous Silicon  

Science Journals Connector (OSTI)

A population analysis of the one-electron eigenfunctions of random-network models of amorphous silicon shows fluctuations of the net atomic charge of about 0.2 electron units rms. The majority of the charge is calculable from a linear function of the deviations of first-neighbor distance and of the interbond angle from their values in the crystal.

Lester Guttman, W. Y. Ching, and Jagannath Rath

1980-06-09T23:59:59.000Z

190

Structure disorder degree of polysilicon thin films grown by different processing: Constant C from Raman spectroscopy  

SciTech Connect (OSTI)

Flat, low-stress, boron-doped polysilicon thin films were prepared on single crystalline silicon substrates by low pressure chemical vapor deposition. It was found that the polysilicon films with different deposition processing have different microstructure properties. The confinement effect, tensile stresses, defects, and the Fano effect all have a great influence on the line shape of Raman scattering peak. But the effect results are different. The microstructure and the surface layer are two important mechanisms dominating the internal stress in three types of polysilicon thin films. For low-stress polysilicon thin film, the tensile stresses are mainly due to the change of microstructure after thermal annealing. But the tensile stresses in flat polysilicon thin film are induced by the silicon carbide layer at surface. After the thin film doped with boron atoms, the phenomenon of the tensile stresses increasing can be explained by the change of microstructure and the increase in the content of silicon carbide. We also investigated the disorder degree states for three polysilicon thin films by analyzing a constant C. It was found that the disorder degree of low-stress polysilicon thin film larger than that of flat and boron-doped polysilicon thin films due to the phase transformation after annealing. After the flat polysilicon thin film doped with boron atoms, there is no obvious change in the disorder degree and the disorder degree in some regions even decreases.

Wang, Quan, E-mail: wangq@mail.ujs.edu.cn [School of mechanical engineering, Jiangsu University, Zhenjiang 212013 (China); State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Zhang, Yanmin; Hu, Ran; Ren, Naifei [School of mechanical engineering, Jiangsu University, Zhenjiang 212013 (China); Ge, Daohan [School of mechanical engineering, Jiangsu University, Zhenjiang 212013 (China); State Key Laboratory of Transducer Technology, Chinese Academy of Sciences, Shanghai 200050 (China)

2013-11-14T23:59:59.000Z

191

Hybrid Thin Film Deposition System | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Hybrid Thin Film Deposition System Hybrid Thin Film Deposition System Only available at EMSL, the Discovery Deposition System has been customized to be a fully automated...

192

Thin Film Solar Technologies | Open Energy Information  

Open Energy Info (EERE)

Jump to: navigation, search Name: Thin Film Solar Technologies Place: South Africa Product: Producers of thin-film copper, indium, gallium, sulphur, selenium modules....

193

High Growth Rate Deposition of Hydrogenated Amorphous Silicon-Germanium Films and Devices Using ECR-PECVD  

SciTech Connect (OSTI)

Hydrogenated amorphous silicon germanium films (a-SiGe:H) and devices have been extensively studied because of the tunable band gap for matching the solar spectrum and mature the fabrication techniques. a-SiGe:H thin film solar cells have great potential for commercial manufacture because of very low cost and adaptability to large-scale manufacturing. Although it has been demonstrated that a-SiGe:H thin films and devices with good quality can be produced successfully, some issues regarding growth chemistry have remained yet unexplored, such as the hydrogen and inert-gas dilution, bombardment effect, and chemical annealing, to name a few. The alloying of the SiGe introduces above an order-of-magnitude higher defect density, which degrades the performance of the a-SiGe:H thin film solar cells. This degradation becomes worse when high growth-rate deposition is required. Preferential attachment of hydrogen to silicon, clustering of Ge and Si, and columnar structure and buried dihydride radicals make the film intolerably bad. The work presented here uses the Electron-Cyclotron-Resonance Plasma-Enhanced Chemical Vapor Deposition (ECR-PECVD) technique to fabricate a-SiGe:H films and devices with high growth rates. Helium gas, together with a small amount of H{sub 2}, was used as the plasma species. Thickness, optical band gap, conductivity, Urbach energy, mobility-lifetime product, I-V curve, and quantum efficiency were characterized during the process of pursuing good materials. The microstructure of the a-(Si,Ge):H material was probed by Fourier-Transform Infrared spectroscopy. They found that the advantages of using helium as the main plasma species are: (1) high growth rate--the energetic helium ions break the reactive gas more efficiently than hydrogen ions; (2) homogeneous growth--heavy helium ions impinging on the surface promote the surface mobility of the reactive radicals, so that heteroepitaxy growth as clustering of Ge and Si, columnar structure are reduced; (3) surface hydrogen removal--heavier and more energetic helium ions break the Si-H much easier than hydrogen ions. The preferential attachment of Si-H to Ge-H is reduced. They also found that with the small amount of hydrogen put into the plasma, the superior properties of a-(Si,Ge):H made from pure hydrogen dilution plasma were still maintained. These hydrogen ions help to remove the subsurface weakly bonded hydrogen and buried hydrogen. They also help to passivate the Ge-dangling bond.

Yong Liu

2002-05-31T23:59:59.000Z

194

Designing Randomness - The Impact of Textured Surfaces on the Efficiency of Thin-Film Solar Cells  

Science Journals Connector (OSTI)

We analyze experimentally and theoretically light localization at randomly textured ZnO surfaces and light absorption in thin-film amorphous Si deposited conformal on it. Guidance is...

Beckers, Thomas; Bittkau, Karsten; Carius, Reinhard; Fahr, Stephan; Rockstuhl, Carsten; Lederer, Falk

195

Micro/nano devices fabricated from Cu-Hf thin films  

DOE Patents [OSTI]

An all-metal microdevice or nanodevice such as an atomic force microscope probe is manufactured from a copper-hafnium alloy thin film having an x-ray amorphous microstructure.

Luber, Erik J; Ophus, Colin; Mitlin, David; Olsen, Brian; Harrower, Christopher; Radmilovi, Velimir

2013-06-04T23:59:59.000Z

196

Deposition of device quality low H content, amorphous silicon films  

DOE Patents [OSTI]

A high quality, low hydrogen content, hydrogenated amorphous silicon (a-Si:H) film is deposited by passing a stream of silane gas (SiH{sub 4}) over a high temperature, 2,000 C, tungsten (W) filament in the proximity of a high temperature, 400 C, substrate within a low pressure, 8 mTorr, deposition chamber. The silane gas is decomposed into atomic hydrogen and silicon, which in turn collides preferably not more than 20--30 times before being deposited on the hot substrate. The hydrogenated amorphous silicon films thus produced have only about one atomic percent hydrogen, yet have device quality electrical, chemical, and structural properties, despite this lowered hydrogen content. 7 figs.

Mahan, A.H.; Carapella, J.C.; Gallagher, A.C.

1995-03-14T23:59:59.000Z

197

Amorphous Silicon-Carbon Nanostructure Photovoltaic Devices  

E-Print Network [OSTI]

film is deposited over the window. . . . . . . . . . . . . . . . . . . . . . . . .A carbon film is deposited over the window. Figure 4.11:films and the silicon is unknown. However, changes in geometry such as varying the window

Schriver, Maria Christine

2012-01-01T23:59:59.000Z

198

Mode Splitting for Efficient Plasmoinc Thin-film Solar Cell  

E-Print Network [OSTI]

We propose an efficient plasmonic structure consisting of metal strips and thin-film silicon for solar energy absorption. We numerically demonstrate the absorption enhancement in symmetrical structure based on the mode coupling between the localized plasmonic mode in Ag strip pair and the excited waveguide mode in silicon slab. Then we explore the method of symmetry-breaking to excite the dark modes that can further enhance the absorption ability. We compare our structure with bare thin-film Si solar cell, and results show that the integrated quantum efficiency is improved by nearly 90% in such thin geometry. It is a promising way for the solar cell.

Li, Tong; Jiang, Chun

2010-01-01T23:59:59.000Z

199

Innovative Characterization of Amorphous and Thin-Film Silicon for Improved Module Performance: 28 April 2005 - 15 September 2008  

SciTech Connect (OSTI)

This report focuses on (1) characterizing nc-Si:H from United Solar; (2) studying Si,Ge:H alloys deposited by HWCVD; and (3) characterizing CIGS films and relating to cell performance parameters.

Cohen, J. D.

2009-12-01T23:59:59.000Z

200

304 JOURNAL OF DISPLAY TECHNOLOGY, VOL. 3, NO. 3, SEPTEMBER 2007 Amorphous Silicon Thin-Film Transistor Backplanes  

E-Print Network [OSTI]

for technical collaboration. The work of A. Z. Kattamis was supported by a fellowship from the Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ. A. Z. Kattamis, I.-C. Cheng, K. Long, B. Hekmatshoar, K. H. Cherenack, S. Wagner, and J. C. Sturm are with the Electrical Engineering and the Princeton

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

CFN | Thin Films Group  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Materials Synthesis and Characterization Facility Materials Synthesis and Characterization Facility Thin-Film Processing Facility Online Manager (FOM) website FOM manual ESR for lab 1L32 (High-Resolution SEM and x-ray microanalysis) CFN Operations Safety Awareness (COSA) form for 1L32 (ESR #1) Technical article on LABE detector (Analytical SEM) Request form for off-hours access (.doc, First time only, renewals done via email) Lab Tool capabilities Primary contact Training schedule Backup contact Booking calendar Booking rules SOP 1L32 Analytical SEM Camino Thurs 10-12 PM Stein FOM yes yes Hitachi S-4800 SEM Stein Tues 1-3 PM Black FOM no yes booking calendar: yes = need to reserve tool time in calendar before using tool booking rules: yes = specific rules exist for reserving tool time SOP = standard operating procedure (basic instructions)

202

Ferromagnetic thin films  

DOE Patents [OSTI]

A ferromagnetic [delta]-Mn[sub 1[minus]x]Ga[sub x] thin film having perpendicular anisotropy is described which comprises: (a) a GaAs substrate, (b) a layer of undoped GaAs overlying said substrate and bonded thereto having a thickness ranging from about 50 to about 100 nanometers, (c) a layer of [delta]-Mn[sub 1[minus]x]Ga[sub x] overlying said layer of undoped GaAs and bonded thereto having a thickness ranging from about 20 to about 30 nanometers, and (d) a layer of GaAs overlying said layer of [delta]-Mn[sub 1[minus]x]Ga[sub x] and bonded thereto having a thickness ranging from about 2 to about 5 nanometers, wherein x is 0.4[+-]0.05. 7 figures.

Krishnan, K.M.

1994-12-20T23:59:59.000Z

203

High-throughput analysis of thin-film stresses using arrays of micromachined cantilever beams  

E-Print Network [OSTI]

High-throughput analysis of thin-film stresses using arrays of micromachined cantilever beams Hyun-throughput residual stress measurements on thin films by means of micromachined cantilever beams and an array of parallel laser beams. In this technique, the film of interest is deposited onto a silicon substrate

204

Photovoltaic manufacturing technology monolithic amorphous silicon modules on continuous polymer substrates: Final technical report, July 5, 1995--December 31, 1999  

SciTech Connect (OSTI)

Iowa Thin Film Technologies is completing a three-phase program that has increased throughput and decreased costs in nearly all aspects of its thin-film photovoltaic manufacturing process. The overall manufacturing costs have been reduced by 61 percent through implementation of the improvements developed under this program. Development of the ability to use a 1-mil substrate, rather than the standard 2-mil substrate, results in a 50 percent cost-saving for this material. Process development on a single-pass amorphous silicon deposition system has resulted in a 37 percent throughput improvement. A wide range of process and machine improvements have been implemented on the transparent conducting oxide deposition system. These include detailed parameter optimization of deposition temperatures, process gas flows, carrier gas flows, and web speeds. An overall process throughput improvement of 275 percent was achieved based on this work. The new alignment technique was developed for the laser scriber and printer systems, which improved registration accuracy from 100 microns to 10 microns. The new technique also reduced alignment time for these registration systems significantly. This resulted in a throughput increase of 75 percent on the scriber and 600 percent on the printer. Automated techniques were designed and implemented for the module assembly processes. These include automated busbar attachment, roll-based lamination, and automated die cutting of finished modules. These processes were previously done by hand labor. Throughput improvements ranged from 200 percent to 1200 percent, relative to hand labor rates. A wide range of potential encapsulation materials were evaluated for suitability in a roll lamination process and for cost-effectiveness. A combination material was found that has a cost that is only 10 percent of the standard EVA/Tefzel cost and is suitable for medium-lifetime applications. The 20-year lifetime applications still require the more expensive material.

Jeffrey, F.

2000-03-28T23:59:59.000Z

205

Rechargeable thin-film lithium batteries  

SciTech Connect (OSTI)

Rechargeable thin-film batteries consisting of lithium metal anodes, an amorphous inorganic electrolyte, and cathodes of lithium intercalation compounds have been fabricated and characterized. These include Li-TiS{sub 2}, Li-V{sub 2}O{sub 5}, and Li-Li{sub x}Mn{sub 2}O{sub 4} cells with open circuit voltages at full charge of about 2.5 V, 3.7 V, and 4.2 V, respectively. The realization of these robust cells, which can be cycled thousands of times, was possible because of the stability of the amorphous lithium electrolyte, lithium phosphorus oxynitride. This material has a typical composition of Li{sub 2.9}PO{sub 3.3}N{sub 0.46}and a conductivity at 25 C of 2 {mu}S/cm. The thin-film cells have been cycled at 100% depth of discharge using current densities of 5 to 100 {mu}A/cm{sup 2}. Over most of the charge-discharge range, the internal resistance appears to be dominated by the cathode, and the major source of the resistance is the diffusion of Li{sup +} ions from the electrolyte into the cathode. Chemical diffusion coefficients were determined from ac impedance measurements.

Bates, J.B.; Gruzalski, G.R.; Dudney, N.J.; Luck, C.F.; Yu, X.

1993-09-01T23:59:59.000Z

206

Thin-film Rechargeable Lithium Batteries  

DOE R&D Accomplishments [OSTI]

Rechargeable thin films batteries with lithium metal anodes, an amorphous inorganic electrolyte, and cathodes of lithium intercalation compounds have been fabricated and characterized. The cathodes include TiS{sub 2}, the {omega} phase of V{sub 2}O{sub 5}, and the cubic spinel Li{sub x}Mn{sub 2}O{sub 4} with open circuit voltages at full charge of about 2.5 V, 3.7 V, and 4.2 V, respectively. The development of these robust cells, which can be cycled thousands of times, was possible because of the stability of the amorphous lithium electrolyte, lithium phosphorus oxynitride. This material has a typical composition of Li{sub 2.9}PO{sub 3.3}N{sub 0.46} and a conductivity at 25 C of 2 {mu}S/cm. Thin film cells have been cycled at 100% depth of discharge using current densities of 2 to 100 {mu}A/cm{sup 2}. The polarization resistance of the cells is due to the slow insertion rate of Li{sup +} ions into the cathode. Chemical diffusion coefficients for Li{sup +} ions in the three types of cathodes have been estimated from the analysis of ac impedance measurements.

Bates, J. B.; Gruzalski, G. R.; Dudney, N. J.; Luck, C. F.; Yu, X.

1993-11-00T23:59:59.000Z

207

Technological development for commercialization of amorphous silicon based multijunction modules  

SciTech Connect (OSTI)

Some of the significant steps in technological development for large-scale commercialization of amorphous silicon (a-Si:H) based multijunction photovoltaic modules are presented. These developments are establishing a high quality baseline process for manufacturing large-area ({approximately}8 ft{sup 2}) a-Si:H/a-SiGe:H tandem junction modules with improved stabilized conversion efficiency, throughput, yield, and reduced materials usage.

Yang, L.; Bennett, M.; Chen, L. [Solarex, Newtown, PA (United States)] [and others

1996-12-31T23:59:59.000Z

208

Optically induced conductivity changes in amorphous silicon: A historical perspective  

SciTech Connect (OSTI)

A historical perspective of the discovery of optically induced changes in amorphous silicon is presented in this paper from my personal point of view. It includes the story of how Chris Wronski and the author discovered the effect, the key elements in the R and D environment that lead to the quick realization that the effect was reversible and reproducible, how the research environment supported the rapid publication of their first paper, and a brief look at the effect from today's perspective.

Staebler, D.L.

1997-07-01T23:59:59.000Z

209

Systematic investigation of picosecond photoinduced absorption in hydrogenated amorphous silicon  

Science Journals Connector (OSTI)

A systematic study of the dependence of picosecond photoinduced absorption (PA) and transmission in hydrogenated amorphous silicon on sample thickness, doping concentration, and excitation intensity has been undertaken. Investigations demonstrated that the picosecond PA decays are not caused by recombination at the sample surface nor by deep trapping. The decays are consistent with thermalization within the band tails and doping-induced band-tail states.

W. B. Jackson; C. Doland; C. C. Tsai

1986-08-15T23:59:59.000Z

210

Short-and intermediate-range structural correlations in amorphous silicon carbide: A molecular dynamics study  

E-Print Network [OSTI]

Short- and intermediate-range structural correlations in amorphous silicon carbide: A molecular-range structural correlations in amorphous silicon carbide a-SiC are studied in terms of partial pair distributions.43.Dq, 61.43.Bn, 61.66.Dk, 81.05.Gc I. INTRODUCTION Silicon carbide SiC has been receiving increasing

Southern California, University of

211

Low-band-gap, amorphous-silicon-based alloys by photochemical vapor deposition: Final report, 1 October 1985--30 November 1986  

SciTech Connect (OSTI)

Thin films of hydrogenated amorphous silicon-germanium alloys were deposited by mercury-sensitized photochemical vapor deposition using a novel photo-CVD reactor. Thin films of a-Si/sub 1-x/Ge/sub x/:H with 0 less than or equal to x less than or equal to 1 and 1.0 less than E/sub g/ less than 1.8 eV were deposited from mixtures of silane and disilane with germane and inert gas diluents at substrate temperatures from 160/degree/ to 200/degree/C. Alloy films were characterized by measurements of photo- and dark conductivity, electron mobility-lifetime product, sub-band-gap absorption, and density of states. Dilution with hydrogen increased the photoconductivity to 10/sup /minus/5/ Scm and mobility-lifetime product to 6 /times/ 10/sup /minus/8/ cm/sup 2/V for alloys having a band gap of 1.4 eV.

Baron, B.N.; Hegedus, S.S.; Jackson, S.C.

1988-02-01T23:59:59.000Z

212

Low-band-gap, amorphous-silicon-based alloys by chemical vapor deposition: Annual subcontract report, 1 October 1985-31 January 1986  

SciTech Connect (OSTI)

This research was conducted to determine the potential of photochemical vapor deposition (photo-CVD) for producing high-quality, low-band-gap amorphous silicon germanium alloys for use in high-efficiency, multijunction, thin-film photovoltaic solar cells. A photo-CVD reactor for mercury-sensitized photolysis of silane-germane and disilane-germane mixtures was developed. Alloy thin films of undoped a-Si/sub 1-x/Ge/sub x/:H were deposited using mercury vapor mixed with SiH/sub 4/ or Si/sub 2/H/sub 6/, GeH/sub 4/, and diluent gas of Ar, He, or H/sub 2/. Materials properties were characterized by measurements of Ge content, optical transmission and reflection, and dark and photo-conductivity. Opto-electronic properties of photo-CVD a-Si/sub 1-x/Ge/sub x/:H were found to be comparable to glow discharge and sputtered materials. Moreover, p-i-n solar cells with low-band-gap i-layers were able to be fabricated by photo-CVD.

Baron, B.N.; Jackson, S.C.

1986-12-01T23:59:59.000Z

213

Structure, Morphology, and Optical Properties of Amorphous and...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Morphology, and Optical Properties of Amorphous and Nanocrystalline Gallium Oxide Thin Films. Structure, Morphology, and Optical Properties of Amorphous and Nanocrystalline Gallium...

214

Improved method of preparing p-i-n junctions in amorphous silicon semiconductors  

DOE Patents [OSTI]

A method of preparing p/sup +/-i-n/sup +/ junctions for amorphous silicon semiconductors includes depositing amorphous silicon on a thin layer of trivalent material, such as aluminum, indium, or gallium at a temperature in the range of 200/sup 0/C to 250/sup 0/C. At this temperature, the layer of trivalent material diffuses into the amorphous silicon to form a graded p/sup +/-i junction. A layer of n-type doped material is then deposited onto the intrinsic amorphous silicon layer in a conventional manner to finish forming the p/sup +/-i-n/sup +/ junction.

Madan, A.

1984-12-10T23:59:59.000Z

215

Electron-beam-induced information storage in hydrogenated amorphous silicon devices  

DOE Patents [OSTI]

A method for recording and storing information in a hydrogenated amorphous silicon device, comprising: depositing hydrogenated amorphous silicon on a substrate to form a charge collection device; and generating defects in the hydrogenated amorphous silicon device, wherein the defects act as recombination centers that reduce the lifetime of carriers, thereby reducing charge collection efficiency and thus in the charge collection mode of scanning probe instruments, regions of the hydrogenated amorphous silicon device that contain the defects appear darker in comparison to regions of the device that do not contain the defects, leading to a contrast formation for pattern recognition and information storage.

Yacobi, B.G.

1985-03-18T23:59:59.000Z

216

E-Print Network 3.0 - amorphous silicon photovoltaic Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

results for: amorphous silicon photovoltaic Page: << < 1 2 3 4 5 > >> 1 Institute of Energy Conversion University of Delaware Summary: photovoltaics on flexible substrates....

217

E-Print Network 3.0 - amorphous silicon modules Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

search results for: amorphous silicon modules Page: << < 1 2 3 4 5 > >> 1 Institute of Energy Conversion University of Delaware Summary: modules. Consulted for a research...

218

E-Print Network 3.0 - amorphous-silicon solar cells Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

results for: amorphous-silicon solar cells Page: << < 1 2 3 4 5 > >> 1 Institute of Energy Conversion University of Delaware Summary: modules. Consulted for a research...

219

E-Print Network 3.0 - amorphous silicon flat-panel Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

with the low cost of amorphous and polycrystalline silicon films on non... , such as solar cells and flat-panel displays, our ACSi technology promises to fundamentally...

220

Optimization-based design of surface textures for thin-film Si solar cells  

E-Print Network [OSTI]

We numerically investigate the light-absorption behavior of thin-film silicon for normal-incident light, using surface textures to enhance absorption. We consider a variety of texture designs, such as simple periodic ...

Sheng, Xing

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Integrated photonic structures for light trapping in thin-film Si solar cells  

E-Print Network [OSTI]

We explore the mechanisms for an efficient light trapping structure for thin-film silicon solar cells. The design combines a distributed Bragg reflector (DBR) and periodic gratings. Using photonic band theories and numerical ...

Sheng, Xing

222

NREL Core Program (NCPV), Session: Film Silicon (Presentation)  

SciTech Connect (OSTI)

This project supports the Solar America Initiative by: R and D that contributes to goal of grid parity by 2015; research to fill the industry R and D pipeline for next-generation low-cost scalable products; development of industry collaborative research; and improvement of NREL tools and capabilities for film silicon research. The project addresses both parts of film silicon roadmap: (1) amorphous-silicon-based thin film PV--amorphous and nanocrystalline materials, present '2nd generation' technology, 4% of world PV sales in 2007; (2) advanced R and D toward film crystal silicon--definition, large-grained or single-crystal silicon < 100 {micro}m thick; 3-8 year horizon; and goal of reaching 15% cells at area costs approaching thin films.

Branz, H. M.

2008-04-01T23:59:59.000Z

223

An Investigation of the Properties of Silicon Nitride (SiNx) Thin Films Prepared by RF Sputtering for Application in Solar Cell Technology  

Science Journals Connector (OSTI)

Silicon nitride films deposited on glass and multicrystalline silicon by RF sputtering with power between 100–350W. The target was hot pressed Si3N4 ceramic. The morphology and optical properties of films are inv...

Negin Manavizadeh; Alireza Khodayari…

2009-01-01T23:59:59.000Z

224

Thin-film Lithium Batteries  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Thin-Film Battery with Lithium Anode Courtesy of Oak Ridge National Laboratory, Materials Science and Technology Division Thin-Film Lithium Batteries Resources with Additional Information The Department of Energy's 'Oak Ridge National Laboratory (ORNL) has developed high-performance thin-film lithium batteries for a variety of technological applications. These batteries have high energy densities, can be recharged thousands of times, and are only 10 microns thick. They can be made in essentially any size and shape. Recently, Teledyne licensed this technology from ORNL to make batteries for medical devices including electrocardiographs. In addition, new "textured" cathodes have been developed which have greatly increased the peak current capability of the batteries. This greatly expands the potential medical uses of the batteries, including transdermal applications for heart regulation.'

225

Mass spectrometric studies of impurities in silane and their effects on the electronic properties of hydrogenated amorphous silicon  

SciTech Connect (OSTI)

The concentration of volatile impurities in silane (SiH/sub 4/) and disilane (Si/sub 2/H/sub 6/) used to prepare hydrogenated amorphous silicon (a-Si:H) thin films by glow-discharge deposition has been measured by modulated molecular beam mass spectrometry with a sensitivity of 1 ppm. From dark conductivity measurements on these films the location of the Fermi energy E/sub F/ was determined. The Fermi levels of a-Si:H films were progressively lower with increasing concentrations of chlorine-containing molecules (mostly HCl and SiH/sub 3/Cl) in the silane, indicating that these species can act as weak p-type dopants in a-Si:H. Oxygen-containing species (mostly SiH/sub 3/OSiH/sub 3/) were also detected in silane. It is clear from these results that large variations in electronic properties of glow discharge a-Si:H can be attributed to differences in purity of silane used in the deposition.

Corderman, R.R.; Vanier, P.E.

1983-07-01T23:59:59.000Z

226

Structure and dielectric properties of La{sub x}Hf{sub (1?x)}O{sub y} thin films: The dependence of components  

SciTech Connect (OSTI)

Graphical abstract: - Highlights: • La{sub x}Hf{sub (1?x)}O{sub y} thin films were grown by pulse laser deposition method. • The thin film with 10% La/(La + Hf) atom ratio forms a cubic HfO{sub 2} phase. • The amorphous thin films due to more La introduced have almost same local structure. • The main infrared phonon modes move to lower frequency for the amorphous thin films. • The static dielectric constants of the amorphous thin films increase with La content. - Abstract: La{sub x}Hf{sub (1?x)}O{sub y} (x = 0, 0.1, 0.3, 0.5, 0.7, y=2?(1/2)x) thin films were grown by pulsed laser deposition (PLD) method. The component dependence of the structure and vibration properties of these thin films is studied by combining X-ray diffraction, X-ray absorption fine structure (XAFS) and infrared spectroscopy. The thin film with 10% La/(La + Hf) atom ratio forms a cubic HfO{sub 2} phase and it has the largest static dielectric constant. More La atoms introduced cause amorphous phase formed and the static dielectric constants increase with the La content. Although XAFS indicates that these amorphous thin films have almost same local structures, the infrared phonon modes with most contribution to the static dielectric constant move to lower frequency, which results in the component dependence of the dielectric constant.

Qi, Zeming, E-mail: zmqi@ustc.edu.cn [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029 (China); Cheng, Xuerui [Department of Technology and Physics, Zhengzhou University of Light Industry, Zhengzhou, Henan 450002 (China); Zhang, Guobin [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029 (China); Li, Tingting [Institute of Microelectronics of Chinese Academy of Science, Beijing 100029 (China); Wang, Yuyin; Shao, Tao; Li, Chengxiang; He, Bo [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029 (China)

2013-07-15T23:59:59.000Z

227

Thermopower and conductivity activation energies in hydrogenated amorphous silicon  

SciTech Connect (OSTI)

The long range fluctuation model has been widely used to account for the difference in activation energies seen experimentally in dark conductivity and thermopower measurements in hydrogenated amorphous silicon. The authors report on a test of this model using measurements of the conductivity and thermoelectric effects carried out in both open and short circuit configurations. While the thermopower activation energy is less than that of the dark conductivity, the short circuit Seebeck conductivity is found to be nearly identical to the dark conductivity in both activation energy and magnitude, consistent with the long range fluctuation model.

Dyalsingh, H.M.; Kakalios, J. [Univ. of Minnesota, Minneapolis, MN (United States). School of Physics and Astronomy

1996-12-31T23:59:59.000Z

228

Metal-semiconductor hybrid thin films in field-effect transistors  

SciTech Connect (OSTI)

Metal-semiconductor hybrid thin films consisting of an amorphous oxide semiconductor and a number of aluminum dots in different diameters and arrangements are formed by electron beam lithography and employed for thin-film transistors (TFTs). Experimental and computational demonstrations systematically reveal that the field-effect mobility of the TFTs enhances but levels off as the dot density increases, which originates from variations of the effective channel length that strongly depends on the electric field distribution in a transistor channel.

Okamura, Koshi, E-mail: koshi.okamura@kit.edu; Dehm, Simone [Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany)] [Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany); Hahn, Horst [Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany) [Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), 76021 Karlsruhe (Germany); KIT-TUD Joint Research Laboratory Nanomaterials, Technische Universität Darmstadt, Petersenstr. 32, 64287 Darmstadt (Germany)

2013-12-16T23:59:59.000Z

229

Chemical vapor deposition of boron-doped hydrogenated amorphous silicon  

SciTech Connect (OSTI)

Deposition conditions and film properties for a variety of boron-doped hydrogenated amorphous silicon films and silicon-carbon films produced by chemical vapor deposition (CVD) are discussed. Deposition gases include monosilane, disilane, trisilane, and acetylene. Two types of optically wide band-gap p layers are obtained. One of these window p layers (without carbon) has been extensively tested in photovoltaic devices. Remarkably, this p layer can be deposited between about 200 to 300 /sup 0/C. A typical open circuit voltage in an all CVD p-i-n device is 0.70--0.72 V, and in a hybrid device where the i and n layers are deposited by glow discharge, 0.8--0.83 V.

Ellis F.B. Jr.; Delahoy, A.E.

1985-07-15T23:59:59.000Z

230

LASER TRANSFER DOPING USING AMORPHOUS SILICON Rafel Ferr (Correspondence author)1  

E-Print Network [OSTI]

LASER TRANSFER DOPING USING AMORPHOUS SILICON Rafel Ferré (Correspondence author)1 , Ralf Gogolin1@isfh.de ABSTRACT: We demonstrate and characterize "Laser Transfer Doping" (LTD) for producing locally doped regions. For this purpose we use nanosecond pulsed laser for transferring phosphorus doped amorphous silicon from a carrier

231

Sputtered pin amorphous silicon semi-conductor device and method therefor  

DOE Patents [OSTI]

A high efficiency amorphous silicon PIN semi-conductor device is constructed by the sequential sputtering of N, I and P layers of amorphous silicon and at least one semi-transparent ohmic electrode. A method of construction produces a PIN device, exhibiting enhanced physical integrity and facilitates ease of construction in a singular vacuum system and vacuum pump down procedure.

Moustakas, Theodore D. (Berkeley Heights, NJ); Friedman, Robert A. (Milford, NJ)

1983-11-22T23:59:59.000Z

232

Amorphous silicon-carbon alloys and amorphous carbon from direct methane and ethylene activation by ECR  

SciTech Connect (OSTI)

Hydrogenated amorphous silicon-carbon alloys are prepared using electron-cyclotron resonance (ECR) plasma-enhanced chemical vapor deposition. Hydrogen is introduced into the source resonance cavity as an excitation gas. Silane is introduced in the main chamber in the vicinity of the plasma stream, whereas the carbon source gases, methane or ethylene, are introduced either with the silane or with the hydrogen as excitation gases. The effect of the type of carbon-source gas, excitation gas mixture and silane-to-carbon source gas flow ratio on the deposition rate, bandgap, subgap density of states, spin density and hydrogen evolution are studied.

Conde, J.P.; Chu, V.; Giorgis, F.; Pirri, C.F.; Arekat, S.

1997-07-01T23:59:59.000Z

233

Chemical vapor deposition of amorphous silicon films from disilane  

SciTech Connect (OSTI)

Amorphous silicon films for fabrication of solar cells have been deposited by thermal chemical vapor deposition (CVD) from disilane (Si/sub 2/H/sub 6/) using a tubular flow reactor. A mathematical description for the CVD reactor was developed and solved by a numerical procedure. The proposed chemical reaction network for the model is based on silylene (SiH/sub 2/) insertion in the gas phase and film growth from SiH/sub 2/ and silicon polymers (Si/sub n/N/sub 2n/, n approx. 10). Estimates of the rate constants have been obtained for trisilane decomposition, silicon polymer formation, and polymer dehydrogenation. The silane unimolecular decomposition rate constants were corrected for pressure effects. The model behavior is compared to the experimental results over the range of conditions: reactor temperature (360 to 485/sup 0/C), pressures (2 to 48 torr), and gas holding time (1 to 70 s). Within the above range of conditions, film growth rate varies from 0.01 to 30 A/s. Results indicate that silicon polymers are the main film precursors for gas holding times greater than 3 s. Film growth by silylene only becomes important at short holding times, large inert gas dilution, and positions near the beginning of the reactor hot zone.

Bogaert, R.J.

1986-01-01T23:59:59.000Z

234

Thin Film CIGS and CdTe Photovoltaic Technologies: Commercialization, Critical Issues, and Applications; Preprint  

SciTech Connect (OSTI)

We report here on the major commercialization aspects of thin-film photovoltaic (PV) technologies based on CIGS and CdTe (a-Si and thin-Si are also reported for completeness on the status of thin-film PV). Worldwide silicon (Si) based PV technologies continues to dominate at more than 94% of the market share, with the share of thin-film PV at less than 6%. However, the market share for thin-film PV in the United States continues to grow rapidly over the past several years and in CY 2006, they had a substantial contribution of about 44%, compared to less than 10% in CY 2003. In CY 2007, thin-film PV market share is expected to surpass that of Si technology in the United States. Worldwide estimated projections for CY 2010 are that thin-film PV production capacity will be more than 3700 MW. A 40-MW thin-film CdTe solar field is currently being installed in Saxony, Germany, and will be completed in early CY 2009. The total project cost is Euro 130 million, which equates to an installed PV system price of Euro 3.25/-watt averaged over the entire solar project. This is the lowest price for any installed PV system in the world today. Critical research, development, and technology issues for thin-film CIGS and CdTe are also elucidated in this paper.

Ullal, H. S.; von Roedern, B.

2007-09-01T23:59:59.000Z

235

Improved amorphous silicon alloy solar cells for module fabrication  

SciTech Connect (OSTI)

An initial conversion efficiency of 13.5% has been obtained on a triple-junction triple-bandgap device fabricated in a large-area deposition reactor capable of producing one-square-foot modules. The intrinsic layer of the top cell is a wide bandgap amorphous silicon alloy. The middle and bottom cells employ high quality amorphous silicon-germanium alloy. The high efficiency of the triple-junction cell is attributed to the relative reduction of the optical loss in the top tunnel junction and the improvement in the quality of the middle and bottom component cells. Triple-junction devices with initial efficiency of 13.3% have shown saturation at 11.6% after light soaking. Modules of aperture area 909 cm{sup 2} have been fabricated using an assembly process similar to the one being currently used in their manufacturing line. The module design consists of one large-area, high-current monolithic multijunction device. The status of the small-area devices and modules is described.

Banerjee, A.; Yang, J.; Guha, S.

1997-07-01T23:59:59.000Z

236

Vertically Aligned Nanocomposite Thin Films  

E-Print Network [OSTI]

nanocomposite oxides have attracted extensive research interest. Nanocomposites consist of nanosized particles embedded in different materials matrix.8 In recent years, high quality nanocrystalline materials have shown novel physical, chemical, magnetic....................................... 9 1.2.3 Physical properties of oxide thin films........................ 12 1.2.3.1 Electrical and optical properties................. 13 1.2.3.2 Magnetism and magnetotransport properties...

Bi, Zhenxing

2012-07-16T23:59:59.000Z

237

Low temperature deposition and characterization of n- and p-type silicon carbide thin films and associated ohmic and Schottky contacts. Annual report, 1 January-31 December 1992  

SciTech Connect (OSTI)

Single-crystal epitaxial films of cubic Beta(3C)-SiC(111) and AlN(0001) have been deposited on alpha(6H)-SiC(OOO1) substrates oriented 3-4 deg towards 1120 at 1050 deg C via gas-source molecular beam epitaxy using disilane (Si2H6), ethylene (C2H4), thermal evaporation of Al and activated N species derived from an ECR plasma. High resolution transmission electron microscopy revealed that the nucleation and growth of the Beta(3C)-SiC regions occurred primarily on terraces between closely spaced steps. Pseudomorphic bilayer structures containing Beta(3C)-SiC and 2H-AlN have been grown under the same conditions for the first time. HREED and cross-sectional HRTEM showed all layers to be monocrystalline. Initial high temperature chemical interdiffusion studies between SiC and AIN show that all components diffuse very slowly across the interface. AHRTEM and SAS are being used to determine the concentration profiles. Thin film solid solutions of AIN and SiC have been deposited using similar techniques and conditions as the individual compounds. Metal contacts of Ti, Pt and Hf deposited at RT on n-type alpha(6H)-SiC(OOO1) exhibit rectifying behavior with ideality factors between 1.01 and 1.09. The Pt and Hf contacts had leakage currents of 5xl0-8 A/cm2 at -10V. Values of barrier heights for all contacts were within a few tenths of 1.0eV which is indicative that the Fermi level is pinned at the SiC surface.... Films, SiC, AlN, Gas source molecular beam epitaxy, Transmission electron microscopy, Chemical interdiffusion, Metal contacts, Ti, Pt, Hf, Ideality factors, Fermi level pinning.

Davis, R.F.; Nemanich, R.J.; Kern, R.S.; Patterson, R.; Rowland, L.B.

1992-01-01T23:59:59.000Z

238

Oriented niobate ferroelectric thin films for electrical and optical devices  

DOE Patents [OSTI]

Sr.sub.x Ba.sub.1-x Nb.sub.2 O.sub.6, where x is greater than 0.25 and less than 0.75, and KNbO.sub.3 ferroelectric thin films metalorganic chemical vapor deposited on amorphous or cyrstalline substrate surfaces to provide a crystal axis of the film exhibiting a high dielectric susceptibility, electro-optic coefficient, and/or nonlinear optic coefficient oriented preferentially in a direction relative to a crystalline or amorphous substrate surface. Such films can be used in electronic, electro-optic, and frequency doubling components.

Wessels, Bruce W. (Wilmette, IL); Nystrom, Michael J. (Chicago, IL)

2001-01-01T23:59:59.000Z

239

Deposition of device quality, low hydrogen content, amorphous silicon films by hot filament technique using ``safe`` silicon source gas  

DOE Patents [OSTI]

A method is described for producing hydrogenated amorphous silicon on a substrate by flowing a stream of safe (diluted to less than 1%) silane gas past a heated filament. 7 figs.

Mahan, A.H.; Molenbroek, E.C.; Nelson, B.P.

1998-07-07T23:59:59.000Z

240

Research on stable, high-efficiency amorphous silicon multijunction modules  

SciTech Connect (OSTI)

This report describes research on semiconductor and non-semiconductor materials to enhance the performance of multi-band-gap, multijunction panel with an area greater than 900 cm[sup 2] by 1992. Double-junction and triple-junction cells are mode on a Ag/ZnO back reflector deposited on stainless steel substrates. An a-SiGe alloy is used for the i-layer in the bottom and the middle cells; the top cell uses an amorphous silicon alloy. After the evaporation of an antireflection coating, silver grids and bus bars are put on the top surface and the panel is encapsulated in an ethylene vinyl acetate (EVA)/Tefzel structure to make a 1-ft[sup 2] monolithic module.

Guha, S. (United Solar Systems Corp., Troy, MI (United States))

1992-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Monolithic amorphous silicon modules on continuous polymer substrate  

SciTech Connect (OSTI)

This report examines manufacturing monolithic amorphous silicon modules on a continuous polymer substrate. Module production costs can be reduced by increasing module performance, expanding production, and improving and modifying production processes. Material costs can be reduced by developing processes that use a 1-mil polyimide substrate and multilayers of low-cost material for the front encapsulant. Research to speed up a-Si and ZnO deposition rates is needed to improve throughputs. To keep throughput rates compatible with depositions, multibeam fiber optic delivery systems for laser scribing can be used. However, mechanical scribing systems promise even higher throughputs. Tandem cells and production experience can increase device efficiency and stability. Two alternative manufacturing processes are described: (1) wet etching and sheet handling and (2) wet etching and roll-to-roll fabrication.

Grimmer, D.P. (Iowa Thin Film Technologies, Inc., Ames, IA (United States))

1992-03-01T23:59:59.000Z

242

ESR studies on hot-wire amorphous silicon  

SciTech Connect (OSTI)

The authors measure a series of hot-wire (HW) amorphous silicon films grown with hydrogen contents C{sub H} varying between 0.5--17 at.%. From constant photocurrent method (CPM) measurements and the steady-state photocarrier grating method (SSPG) they find good agreement with previous measurements on similar hot-wire films. Electron spin resonance measurements on the same samples, however, yield significantly higher spin densities than expected. A thickness series indicates a highly defective layer close to the substrate interface. They propose that this defective layer may be due to excessive out diffusion of hydrogen during growth at high temperatures, as seen by secondary ion mass spectroscopy. ESR measurements on light-degraded samples indicate an improved stability of samples with C{sub H} < 9 at.%.

Unold, T.; Mahan, A.H.

1997-07-01T23:59:59.000Z

243

Laser induced melting and crystallization of boron doped amorphous silicon  

SciTech Connect (OSTI)

Transient reflectivity experiments have been performed to measure the dynamics of laser-induced melting of amorphous silicon (a-Si) and the crystallization to {micro}c-Si of films with different thicknesses on Corning 7059 glass. The laser-induced melting takes place with a velocity of 13 to 24 m/s, while the solidification is about a factor 10 slower. The crystallization starts at the Si/glass interface and at the surface. In the center of the films Si remains liquid for an extended period of time. The crystallization dynamics point towards an heterogeneous morphology of laser-crystallized Si, where the surface and the interface layers are composed of small grains and the bulk of larger grains.

Nebel, C.E.; Schoeniger, S.; Dahlheimer, B.; Stutzmann, M.

1997-07-01T23:59:59.000Z

244

Optical bandgap of ultra-thin amorphous silicon films deposited on crystalline silicon by PECVD  

SciTech Connect (OSTI)

An optical study based on spectroscopic ellipsometry, performed on ultrathin hydrogenated amorphous silicon (a-Si:H) layers, is presented in this work. Ultrathin layers of intrinsic amorphous silicon have been deposited on n-type mono-crystalline silicon (c-Si) wafers by plasma enhanced chemical vapor deposition (PECVD). The layer thicknesses along with their optical properties –including their refractive index and optical loss- were characterized by spectroscopic ellipsometry (SE) in a wavelength range from 250 nm to 850 nm. The data was fitted to a Tauc-Lorentz optical model and the fitting parameters were extracted and used to compute the refractive index, extinction coefficient and optical bandgap. Furthermore, the a-Si:H film grown on silicon was etched at a controlled rate using a TMAH solution prepared at room temperature. The optical properties along with the Tauc-Lorentz fitting parameters were extracted from the model as the film thickness was reduced. The etch rate for ultrathin a-Si:H layers in TMAH at room temperature was found to slow down drastically as the c-Si interface is approached. From the Tauc-Lorentz parameters obtained from SE, it was found that the a-Si film exhibited properties that evolved with thickness suggesting that the deposited film is non-homogeneous across its depth. It was also found that the degree of crystallinity and optical (Tauc) bandgap increased as the layers were reduced in thickness and coming closer to the c-Si substrate interface, suggesting the presence of nano-structured clusters mixed into the amorphous phase for the region close to the crystalline silicon substrate. Further results from Atomic Force Microscopy and Transmission Electron Microscopy confirmed the presence of an interfacial transitional layer between the amorphous film and the underlying substrate showing silicon nano-crystalline enclosures that can lead to quantum confinement effects. Quantum confinement is suggested to be the cause of the observed increase in the optical bandgap of a-Si:H films close to the a-Si:H/cSi interface.

Abdulraheem, Yaser, E-mail: yaser.abdulraheem@kuniv.edu.kw [Electrical Engineering Department, College of Engineering and Petroleum, Kuwait University. P.O. Box 5969, 13060 Safat (Kuwait); Gordon, Ivan; Bearda, Twan; Meddeb, Hosny; Poortmans, Jozef [IMEC, Kapeldreef 75, 3001, Leuven (Belgium)

2014-05-15T23:59:59.000Z

245

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

DOE Patents [OSTI]

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

Raymond, L.S.

1980-11-12T23:59:59.000Z

246

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

DOE Patents [OSTI]

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

Raymond, Leonard S. (Tucson, AZ)

1983-01-01T23:59:59.000Z

247

Ceramic Thin Films: Fabrication and Applications  

Science Journals Connector (OSTI)

...SPRAYED CERAMIC COATING, JOURNAL...PB1-XCAXTIO3 THIN-FILM GROWN BY...ELECTRICAL, OPTICAL, AND ELECTRO-OPTIC...fabrication and applications. | Ceramics...controlled optical switches...Ceramic coatings ofalumina...modified by the application of mechanical...material as a thin film cannot only...successive coatings. Although...respect to CVD that the...purposes. Applications of Thin Film Ceramics...

M. Sayer; K. Sreenivas

1990-03-02T23:59:59.000Z

248

Amorphous Silicon: The other Silicon J.C. Sturm, Y. Huang, L. Han, T. Liu, *B. Hekmatshoar,  

E-Print Network [OSTI]

for cost reduction, and crystalline silicon- amorphous silicon interfaces for high performance solar cells for analog and high duty cycle applications, flexible substrates for products with new form factors, printing Fig. 2. Pixel circuits for (a) active matrix liquid crystal display and (b) active matrix organic

249

Control of morphology for enhanced electronic transport in PECVD-grown a-Si : H Thin Films  

E-Print Network [OSTI]

Solar cells have become an increasingly viable alternative to traditional, pollution causing power generation methods. Although crystalline silicon (c-Si) modules make up most of the market, thin films such as hydrogenated ...

Castro Galnares, Sebastián

2010-01-01T23:59:59.000Z

250

The growth characteristics of microcrystalline Si thin film deposited by atmospheric pressure plasma-enhanced chemical vapor deposition  

Science Journals Connector (OSTI)

Microcrystalline silicon thin film was grown by atmospheric pressure plasma-enhanced chemical vapor deposition (AP-PECVD) ... with a cylindrical rotary electrode supplied with 150 MHz very-high-frequency power. T...

Jung-Dae Kwon

2013-11-01T23:59:59.000Z

251

A novel integrated structure of thin film GaN LED with ultra-low thermal resistance  

Science Journals Connector (OSTI)

This study proposes a novel packaging structure for vertical thin-GaN LED applications by integration of LED chip and silicon-based packaging process. The vertical thin film LED is...

Wen, Shih-Yi; Hu, Hung-Lieh; Tsai, Yao-Jun; Hsu, Chen-Peng; Lin, Re-Ching; Horng, Ray Hua

2014-01-01T23:59:59.000Z

252

Optical losses in amorphous silicon solar cells due to back reflectors  

SciTech Connect (OSTI)

The authors have used a new numerical model and here present initial results on how texturing and backreflectors affect the maximum achievable short-circuit current densities in amorphous silicon solar cells.

Sopori, B.L.; Madjdpour, J.; Von Roedern, B.; Chen, W.; Hegedus, S.S.

1997-07-01T23:59:59.000Z

253

RF sputtering for controlling dihydride and monohydride bond densities in amorphous silicon hydride  

DOE Patents [OSTI]

A process is described for controlling the dihydride and monohydride bond densities in hydrogenated amorphous silicone produced by reactive rf sputtering of an amorphous silicon target. There is provided a chamber with an amorphous silicon target and a substrate therein with the substrate and the target positioned such that when rf power is applied to the target the substrate is in contact with the sputtering plasma produced thereby. Hydrogen and argon are fed to the chamber and the pressure is reduced in the chamber to a value sufficient to maintain a sputtering plasma therein, and then rf power is applied to the silicon target to provide a power density in the range of from about 7 watts per square inch to about 22 watts per square inch to sputter an amorphous solicone hydride onto the substrate, the dihydride bond density decreasing with an increase in the rf power density. Substantially pure monohydride films may be produced.

Jeffery, F.R.; Shanks, H.R.

1980-08-26T23:59:59.000Z

254

Plasmonic Thin-Film Solar Cells  

Science Journals Connector (OSTI)

A combined computational-experimental study optimizing plasmon-enhanced absorption in thin film solar cells presented. We investigate the effect of different geometries where...

Pala, Ragip; White, Justin; Brongersma, Mark

255

Atomic-scale characterization of hydrogenated amorphous-silicon films and devices. Annual subcontract report, 14 February 1995--14 April 1996  

SciTech Connect (OSTI)

The research is concerned with improving the electronic properties of hydrogenated amorphous silicon (a-Si:H) films and of photovoltaic (PV) cells that use these films. Two approaches toward this goal are being taken. One is to establish the character of silicon particle growth in the rf glow discharges that are used to make the films and PV cells, and to understand the particle incorporation into the films. The ultimate goal of this effort is to find mitigation techniques that minimize the particle incorporation. During this contract period, the authors have developed a novel particle light-scattering technique that provides a very detailed and sensitive diagnostic of the particles suspended in the discharge. The second program is directed toward measuring the electronic properties of these thin-film PV cells, as a function of depth within the cell. The approach being taken is to use a scanning tunneling microscope (STM) to measure the depth-dependent electronic properties of cross-sectioned PV cells. During the present period, cell cleaving and cross section locating methods, both in a UHV environment, have been successfully developed.

Gallagher, A.; Barzen, S.; Childs, M.; Laracuente, A. [National Inst. of Standards and Technology, Boulder, CO (United States)

1997-02-01T23:59:59.000Z

256

Thin film solar energy collector  

DOE Patents [OSTI]

A multi-layer solar energy collector of improved stability comprising: (1) a substrate of quartz, silicate glass, stainless steel or aluminum-containing ferritic alloy; (2) a solar absorptive layer comprising silver, copper oxide, rhodium/rhodium oxide and 0-15% by weight of platinum; (3) an interlayer comprising silver or silver/platinum; and (4) an optional external anti-reflective coating, plus a method for preparing a thermally stable multi-layered solar collector, in which the absorptive layer is undercoated with a thin film of silver or silver/platinum to obtain an improved conductor-dielectric tandem.

Aykan, Kamran (Monmouth Beach, NJ); Farrauto, Robert J. (Westfield, NJ); Jefferson, Clinton F. (Millburn, NJ); Lanam, Richard D. (Westfield, NJ)

1983-11-22T23:59:59.000Z

257

Thin film buried anode battery  

DOE Patents [OSTI]

A reverse configuration, lithium thin film battery (300) having a buried lithium anode layer (305) and process for making the same. The present invention is formed from a precursor composite structure (200) made by depositing electrolyte layer (204) onto substrate (201), followed by sequential depositions of cathode layer (203) and current collector (202) on the electrolyte layer. The precursor is subjected to an activation step, wherein a buried lithium anode layer (305) is formed via electroplating a lithium anode layer at the interface of substrate (201) and electrolyte film (204). The electroplating is accomplished by applying a current between anode current collector (201) and cathode current collector (202).

Lee, Se-Hee (Lakewood, CO); Tracy, C. Edwin (Golden, CO); Liu, Ping (Denver, CO)

2009-12-15T23:59:59.000Z

258

Cobalt cluster-assembled thin films deposited by low energy cluster beam deposition: Structural and magnetic investigations of deposited layers  

SciTech Connect (OSTI)

Cobalt cluster-assembled thin films were deposited on amorphous-carbon-coated copper grids and on silicon substrates at room temperature by low energy cluster beam deposition. Characterizations using high-resolution transmission electronic microscopy and atomic force microscopy reveal randomly stacked agglomerates of 9-11 nm diameter, which are themselves composed of small 3.6 nm diameter fcc cobalt clusters. The films are ferromagnetic up to room temperature and above, which implies that the clusters are exchange coupled. The approach to saturation is analyzed within the random anisotropy model. The values of the exchange coefficient A and the anisotropy constant K then derived are discussed. The temperature dependence of the coercivity below 100 K is discussed in terms of thermal activation effects. All results indicate that the fundamental entity governing the magnetic behaviors is constituted by the 9-11 nm diameter agglomerates rather than by the clusters themselves.

Dumas-Bouchiat, F.; Nagaraja, H. S.; Rossignol, F.; Champeaux, C.; Trolliard, G.; Catherinot, A.; Givord, D. [Centre de Projet Films Minces et Microdispositifs pour Telecommunications, SPCTS, UMR CNRS 6638, 123 Avenue Albert Thomas, 87060 Limoges Cedex (France); SPCTS, UMR CNRS 6638, ENSCI, 47 Avenue Albert Thomas, 87065 Limoges Cedex (France); Centre de Projet Films Minces et Microdispositifs pour Telecommunications, SPCTS, UMR CNRS 6638, 123 Avenue Albert Thomas, 87060 Limoges Cedex (France); SPCTS, UMR CNRS 6638, 123 Avenue Albert Thomas, 87060 Limoges Cedex (France); Centre de Projet Films Minces et Microdispositifs pour Telecommunications, SPCTS, UMR CNRS 6638, 123 Avenue Albert Thomas, 87060 Limoges Cedex (France); Laboratoire Louis Neel, UPR CNRS 5051, BP 166, F-38042 Grenoble Cedex (France)

2006-09-15T23:59:59.000Z

259

Thin-Film Reliability Trends Toward Improved Stability  

SciTech Connect (OSTI)

Long-term, stable performance of photovoltaic (PV) modules will be increasingly important to their successful penetration of the power grid. This paper summarizes more than 150 thin-film and more than 1700 silicon PV degradation rates (R{sub d}) quoted in publications for locations worldwide. Partitioning the literature results by technology and date of installation statistical analysis shows an improvement in degradation rate especially for thin-film technologies in the last decade. A CIGS array deployed at NREL for more than 5 years that appears to be stable supports the literature trends. Indoor and outdoor data indicate undetectable change in performance (0.2 {+-} 0.2 %/yr). One module shows signs of slight degradation from what appears to be an initial manufacturing defect, however it has not affected the overall system performance.

Jordan, D. C.; Kurtz, S. R.

2011-01-01T23:59:59.000Z

260

Thin-Film Reliability Trends Toward Improved Stability: Preprint  

SciTech Connect (OSTI)

Long-term, stable performance of photovoltaic (PV) modules will be increasingly important to their successful penetration of the power grid. This paper summarizes more than 150 thin-film and more than 1700 silicon PV degradation rates (Rd) quoted in publications for locations worldwide. Partitioning the literature results by technology and date of installation statistical analysis shows an improvement in degradation rate especially for thin-film technologies in the last decade. A CIGS array deployed at NREL for more than 5 years that appears to be stable supports the literature trends. Indoor and outdoor data indicate undetectable change in performance (0.2+/-0.2 %/yr). One module shows signs of slight degradation from what appears to be an initial manufacturing defect, however it has not affected the overall system performance.

Jordan, D. C.; Kurtz, S. R.

2011-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Amorphization and reduction of thermal conductivity in porous silicon by irradiation with swift heavy ions  

SciTech Connect (OSTI)

In this article, we demonstrate that the thermal conductivity of nanostructured porous silicon is reduced by amorphization and also that this amorphous phase in porous silicon can be created by swift (high-energy) heavy ion irradiation. Porous silicon samples with 41%-75% porosity are irradiated with 110 MeV uranium ions at six different fluences. Structural characterisation by micro-Raman spectroscopy and SEM imaging show that swift heavy ion irradiation causes the creation of an amorphous phase in porous Si but without suppressing its porous structure. We demonstrate that the amorphization of porous silicon is caused by electronic-regime interactions, which is the first time such an effect is obtained in crystalline silicon with single-ion species. Furthermore, the impact on the thermal conductivity of porous silicon is studied by micro-Raman spectroscopy and scanning thermal microscopy. The creation of an amorphous phase in porous silicon leads to a reduction of its thermal conductivity, up to a factor of 3 compared to the non-irradiated sample. Therefore, this technique could be used to enhance the thermal insulation properties of porous Si. Finally, we show that this treatment can be combined with pre-oxidation at 300 Degree-Sign C, which is known to lower the thermal conductivity of porous Si, in order to obtain an even greater reduction.

Newby, Pascal J. [Institut des Nanotechnologies de Lyon, Universite de Lyon, INL-UMR5270, CNRS, INSA de Lyon, Villeurbanne 69621 (France); Institut Interdisciplinaire d'Innovation Technologique (3IT), Universite de Sherbrooke, CNRS UMI-LN2, Sherbrooke, Quebec J1K0A5 (Canada); Canut, Bruno; Bluet, Jean-Marie; Lysenko, Vladimir [Institut des Nanotechnologies de Lyon, Universite de Lyon, INL-UMR5270, CNRS, INSA de Lyon, Villeurbanne 69621 (France); Gomes, Severine [Centre de Thermique de Lyon, Universite de Lyon, CETHIL-UMR5008, CNRS, INSA de Lyon, Villeurbanne 69621 (France); Isaiev, Mykola; Burbelo, Roman [Faculty of Physics, Taras Shevchenko National University of Kyiv, 64/13, Volodymyrs'ka St., Kyiv 01601 (Ukraine); Termentzidis, Konstantinos [Laboratoire LEMTA, Universite de Lorraine-CNRS UMR 7563, 54506 Vandoeuvre-les-Nancy cedex (France); Chantrenne, Patrice [Universite de Lyon, INSA de Lyon, MATEIS-UMR CNRS 5510, Villeurbanne 69621 (France); Frechette, Luc G. [Institut Interdisciplinaire d'Innovation Technologique (3IT), Universite de Sherbrooke, CNRS UMI-LN2, Sherbrooke, Quebec J1K0A5 (Canada)

2013-07-07T23:59:59.000Z

262

Research on stable, high-efficiency amorphous silicon multijunction modules  

SciTech Connect (OSTI)

This report describes research to improve the understanding of amorphous silicon alloys and other relevant non-semiconductor materials for use in high-efficiency, large-area multijunction modules. The research produced an average subcell initial efficiency of 8.8% over a 1-ft{sup 2} area using same-band-gap, dual-junction cells deposited over a ZnO/AlSi back reflector. An initial efficiency of 9.6% was achieved using a ZnO/Ag back reflector over smaller substrates. A sputtering machine will be built to deposit a ZnO/Ag back reflector over a 1-ft{sup 2} area so that a higher efficiency can also be obtained on larger substrates. Calculations have been performed to optimize the grid pattern, bus bars, and cell interconnects on modules. With our present state of technology, we expect a difference of about 6% between the aperture-area and active-area efficiencies of modules. Preliminary experiments show a difference of about 8%. We can now predict the performance of single-junction cells after long-term light exposure at 50{degree}C by exposing cells to short-term intense light at different temperatures. We find that single-junction cells deposited on a ZnO/Ag back reflector show the highest stabilized efficiency when the thickness of the intrinsic layers is about 2000 {angstrom}. 8 refs.

Guha, S. (United Solar Systems Corp., Troy, MI (United States))

1991-12-01T23:59:59.000Z

263

Hydrogenated amorphous silicon produced by pyrolysis and photolysis of disilane  

SciTech Connect (OSTI)

A new class of hydrogenated amorphous silicon (a-Si:H) was prepared by the thermal CVD and photo-CVD of disilane. In the low pressure thermal CVD, the horizontal quartz tube heated by resistance heaters was used as a reactor. The growth rate of the thermal CVD a-Si:H films is plotted as a function of reciprocal substrate temperature. As a new alternative approach to prepare high quality CVD films at temperatures below 300/sup 0/C, the direct photochemical decomposition of disilane has been attempted utilizing a low pressure mercury lamp as a UV radiation source. In the case of undoped and phosphorus doped films, the growth rate is independent of the substrate temperature. In contrast to this, for boron doping, the growth rate has an activation energy of 0.64 eV as in the case of the thermal CVD although the growth rate of the photo-CVD is about three times as large as that of the thermal CVD. This implies that the photoCVD process in boron doping is dominated by the thermal reaction catalyzed with diborane. The dark conductivity and photoconductivity before and after light exposure (AM-1, 200 mW/cm/sup 2/) exhibit no change, indicating the absence of the light-soak degradation in photo-CVD films. The valency control in thermal CVD and photo-CVD is also successfully carried out.

Ashida, Y.; Hirose, M.; Isogaya, K.; Kitagawa, N.; Mishima, Y.; Osuka, Y.

1984-05-01T23:59:59.000Z

264

High efficiency neutron sensitive amorphous silicon pixel detectors  

SciTech Connect (OSTI)

A multi-layer a-Si:H based thermal neutron detector was designed, fabricated and simulated by Monte Carlo method. The detector consists of two PECVD deposited a-Si:H pin detectors interfaced with coated layers of Gd, as a thermal neutron converter. Simulation results indicate that a detector consisting of 2 Gd films with thicknesses of 2 and 4 {mu}m, sandwiched properly with two layers of sufficiently thick ({approximately}30{mu}m) amorphous silicon diodes, has the optimum parameters. The detectors have an intrinsic efficiency of about 42% at a threshold setting of 7000 electrons, with an expected average signal size of {approximately}12000 electrons which is well above the noise. This efficiency will be further increased to nearly 63%, if we use Gd with 50% enrichment in {sup 157}Gd. We can fabricate position sensitive detectors with spatial resolution of 300 {mu}m with gamma sensitivity of {approximately}1 {times} 10{sup {minus}5}. These detectors are highly radiation resistant and are good candidates for use in various application, where high efficiency, high resolution, gamma insensitive position sensitive neutron detectors are needed.

Mireshghi, A.; Cho, G.; Drewery, J.S.; Hong, W.S.; Jing, T.; Lee, H.; Kaplan, S.N.; Perez-Mendez, V.

1993-11-01T23:59:59.000Z

265

Institute of Photo Electronic Thin Film Devices and Technology...  

Open Energy Info (EERE)

Institute of Photo Electronic Thin Film Devices and Technology of Nankai University Jump to: navigation, search Name: Institute of Photo-Electronic Thin Film Devices and Technology...

266

Thickness Dependency of Thin Film Samaria Doped Ceria for Oxygen...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Dependency of Thin Film Samaria Doped Ceria for Oxygen Sensing . Thickness Dependency of Thin Film Samaria Doped Ceria for Oxygen Sensing . Abstract: High temperature oxygen...

267

Direct Measurement of Oxygen Incorporation into Thin Film Oxides...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Measurement of Oxygen Incorporation into Thin Film Oxides at Room Temperature Upon Ultraviolet Phton Irradiation. Direct Measurement of Oxygen Incorporation into Thin Film Oxides...

268

Amorphous silicon/polyaniline heterojunction solar cells: Fermi levels and open-circuit voltages  

E-Print Network [OSTI]

these open-circuit voltages are lower than for the best a-Si:H cells utilizing nanocrystalline Si or a reports on conducting polymer/ amorphous silicon (a-Si:H) structures [1­4] and conduct- ing polymer/crystalline silicon (c-Si) structures [5,6]. In this paper, we report our research on polyaniline (PANI)/a-Si:H

Schiff, Eric A.

269

Electroabsorption measurements and built-in potentials in amorphous silicon pin solar cells  

E-Print Network [OSTI]

and the capacitance of such devices. We apply this technique to hydrogenated amorphous silicon a-Si:H -based solar-6951 96 04246-5 The internal electric fields of amporphous silicon a- Si:H -based p­i­n solar cells on electroluminescent organic heterostructure diodes . We con- firmed this interpretation by studying a-Si:H n

Schiff, Eric A.

270

Thin film solar cell including a spatially modulated intrinsic layer  

DOE Patents [OSTI]

One or more thin film solar cells in which the intrinsic layer of substantially amorphous semiconductor alloy material thereof includes at least a first band gap portion and a narrower band gap portion. The band gap of the intrinsic layer is spatially graded through a portion of the bulk thickness, said graded portion including a region removed from the intrinsic layer-dopant layer interfaces. The band gap of the intrinsic layer is always less than the band gap of the doped layers. The gradation of the intrinsic layer is effected such that the open circuit voltage and/or the fill factor of the one or plural solar cell structure is enhanced.

Guha, Subhendu (Troy, MI); Yang, Chi-Chung (Troy, MI); Ovshinsky, Stanford R. (Bloomfield Hills, MI)

1989-03-28T23:59:59.000Z

271

Zinc oxide thin film acoustic sensor  

SciTech Connect (OSTI)

This paper reports the implementation of (750 nm) thickness of Zinc Oxide (ZnO) thin film for the piezoelectric pressure sensors. The film was prepared and deposited employing the spray pyrolysis technique. XRD results show that the growth preferred orientation is the (002) plane. A polycrystalline thin film (close to mono crystallite like) was obtained. Depending on the Scanning Electron Microscopy photogram, the film homogeneity and thickness were shown. The resonance frequency measured (about 19 kHz) and the damping coefficient was calculated and its value was found to be about (2.5538), the thin film be haves as homogeneous for under and over damped. The thin film pressure sensing was approximately exponentially related with frequency, the thin film was observed to has a good response for mechanical stresses also it is a good material for the piezoelectric properties.

Mohammed, Ali Jasim; Salih, Wafaa Mahdi; Hassan, Marwa Abdul Muhsien; Nusseif, Asmaa Deiaa; Kadhum, Haider Abdullah [Department of Physics , College of Science, Al-Mustansiriyah University, Baghdad (Iraq); Mansour, Hazim Louis [Department of Physics , College of Education, Al-Mustansiriyah University, Baghdad (Iraq)

2013-12-16T23:59:59.000Z

272

The Characteristics of Polysilicon Oxide Grown on Amorphous Silicon Deposited from Disilane  

Science Journals Connector (OSTI)

The characteristics of polysilicon oxide (polyoxide) grown on amorphous silicon deposited from disilane as the silicon source are reported on. The rate of amorphous silicon deposition from disilane is comparable to that of polysilicon deposition from silane. Moreover, the obtained polyoxide has the desirable electrical characteristics of lower leakage current and higher breakdown field than those of polyoxide grown on polysilicon deposition from silane, urgently needed for nonvolatile memory application. At the same time, the grown polysilicon oxides have lower electron trapping rates and larger charge-to-breakdown (Q bd), both attributable to their smoother polyoxide/polysilicon-1 interface than those of polyoxides grown on polysilicon deposition from silane.

Yeou Ming Lin; Tan Fu Lei

1997-01-01T23:59:59.000Z

273

Elasticity, strength, and toughness of single crystal silicon carbide, ultrananocrystalline diamond, and hydrogen-free tetrahedral amorphous  

E-Print Network [OSTI]

Elasticity, strength, and toughness of single crystal silicon carbide, ultrananocrystalline diamond carbide 3C-SiC , ultrananocrystalline diamond, and hydrogen-free tetrahedral amorphous carbon

Espinosa, Horacio D.

274

Ga configurations in hydrogenated amorphous silicon as studied by x-ray photoemission spectroscopy  

Science Journals Connector (OSTI)

Samples of crystalline silicon and glow-discharge-deposited hydrogenated amorphous silicon were doped with gallium by low-energy (4-keV) ion implantation. X-ray photoemission spectroscopy was used to study the chemical-bonding states of the Ga. From Ga 3d core-level studies, we found that elementary interstitial, threefold-coordinated, and fourfold-coordinated Ga coexist in the ion-implanted and annealed amorphous silicon network. The percentage of activated threefold- and fourfold-coordinated Ga atoms is found to increase with increasing annealing temperature, prior to crystallization. The energy released by the amorphous silicon lattice upon annealing contributes to the activation of the gallium from the elementary state to the threefold- or fourfold-coordinated state. No evidence of Ga-H bond formation is found. The percentage of fourfold-coordinated Ga, which we call the doping efficiency, ranges from 5% to 10%, depending upon the thermal treatment.

Z. H. Lu; S. Poulin-Dandurand; E. Sacher; A. Yelon

1990-09-15T23:59:59.000Z

275

Pulsed energy synthesis and doping of silicon carbide  

DOE Patents [OSTI]

A method for producing beta silicon carbide thin films by co-depositing thin films of amorphous silicon and carbon onto a substrate is disclosed, whereafter the films are irradiated by exposure to a pulsed energy source (e.g. excimer laser) to cause formation of the beta-SiC compound. Doped beta-SiC may be produced by introducing dopant gases during irradiation. Single layers up to a thickness of 0.5-1 micron have been produced, with thicker layers being produced by multiple processing steps. Since the electron transport properties of beta silicon carbide over a wide temperature range of 27--730 C is better than these properties of alpha silicon carbide, they have wide application, such as in high temperature semiconductors, including HETEROJUNCTION-junction bipolar transistors and power devices, as well as in high bandgap solar arrays, ultra-hard coatings, light emitting diodes, sensors, etc.

Truher, J.B.; Kaschmitter, J.L.; Thompson, J.B.; Sigmon, T.W.

1995-06-20T23:59:59.000Z

276

Pulsed energy synthesis and doping of silicon carbide  

DOE Patents [OSTI]

A method for producing beta silicon carbide thin films by co-depositing thin films of amorphous silicon and carbon onto a substrate, whereafter the films are irradiated by exposure to a pulsed energy source (e.g. excimer laser) to cause formation of the beta-SiC compound. Doped beta-SiC may be produced by introducing dopant gases during irradiation. Single layers up to a thickness of 0.5-1 micron have been produced, with thicker layers being produced by multiple processing steps. Since the electron transport properties of beta silicon carbide over a wide temperature range of 27.degree.-730.degree. C. is better than these properties of alpha silicon carbide, they have wide application, such as in high temperature semiconductors, including hetero-junction bipolar transistors and power devices, as well as in high bandgap solar arrays, ultra-hard coatings, light emitting diodes, sensors, etc.

Truher, Joel B. (San Rafael, CA); Kaschmitter, James L. (Pleasanton, CA); Thompson, Jesse B. (Brentwood, CA); Sigmon, Thomas W. (Beaverton, OR)

1995-01-01T23:59:59.000Z

277

Excitation mechanism and thermal emission quenching of Tb ions in silicon rich silicon oxide thin films grown by plasma-enhanced chemical vapour deposition—Do we need silicon nanoclusters?  

SciTech Connect (OSTI)

In this work, we will discuss the excitation and emission properties of Tb ions in a Silicon Rich Silicon Oxide (SRSO) matrix obtained at different technological conditions. By means of electron cyclotron resonance plasma-enhanced chemical vapour deposition, undoped and doped SRSO films have been obtained with different Si content (33, 35, 39, 50 at. %) and were annealed at different temperatures (600, 900, 1100?°C). The samples were characterized optically and structurally using photoluminescence (PL), PL excitation, time resolved PL, absorption, cathodoluminescence, temperature dependent PL, Rutherford backscattering spectrometry, Fourier transform infrared spectroscopy and positron annihilation lifetime spectroscopy. Based on the obtained results, we discuss how the matrix modifications influence excitation and emission properties of Tb ions.

Podhorodecki, A., E-mail: artur.p.podhorodecki@pwr.wroc.pl; Golacki, L. W.; Zatryb, G.; Misiewicz, J. [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Wang, J.; Jadwisienczak, W. [School of EECS, Ohio University, Stocker Center 363, Athens, Ohio 45701 (United States); Fedus, K. [Institute of Physics, Nicholas Copernicus University, Grudziadzka 5/7, 87-100 Torun (Poland); Wojcik, J.; Wilson, P. R. J.; Mascher, P. [Department of Engineering Physics and Centre for Emerging Device Technologies, McMaster University, 1280 Main St. W, Hamilton, Ontario L8S4L7 (Canada)

2014-04-14T23:59:59.000Z

278

Geometric shape control of thin film ferroelectrics and resulting structures  

DOE Patents [OSTI]

A monolithic crystalline structure and a method of making involves a semiconductor substrate, such as silicon, and a ferroelectric film, such as BaTiO.sub.3, overlying the surface of the substrate wherein the atomic layers of the ferroelectric film directly overlie the surface of the substrate. By controlling the geometry of the ferroelectric thin film, either during build-up of the thin film or through appropriate treatment of the thin film adjacent the boundary thereof, the in-plane tensile strain within the ferroelectric film is relieved to the extent necessary to permit the ferroelectric film to be poled out-of-plane, thereby effecting in-plane switching of the polarization of the underlying substrate material. The method of the invention includes the steps involved in effecting a discontinuity of the mechanical restraint at the boundary of the ferroelectric film atop the semiconductor substrate by, for example, either removing material from a ferroelectric film which has already been built upon the substrate, building up a ferroelectric film upon the substrate in a mesa-shaped geometry or inducing the discontinuity at the boundary by ion beam deposition techniques.

McKee, Rodney A. (Kingston, TN); Walker, Frederick J. (Oak Ridge, TN)

2000-01-01T23:59:59.000Z

279

BDS thin film damage competition  

SciTech Connect (OSTI)

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

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

2008-10-24T23:59:59.000Z

280

Properties of hydrogenated amorphous silicon prepared by chemical vapor deposition  

SciTech Connect (OSTI)

Hydrogenated amorphous silicon (a-Si:H) films were prepared by chemical vapor deposition (CVD) from mixtures of silane, disilane, trisilane, and higher polysilanes in hydrogen carrier gas at 1 atm total pressure, at substrate temperatures from 420--530 /sup 0/C. Experimental parameters are explained and properties as a function of these parameters are shown. The measurements include hydrogen content (by IR), optical, electrical, and photovoltaic properties of the material. In most respects, the CVD material closely resembles the a-Si:H usually prepared by glow discharge. The following differences have been noted: (1) the CVD a-Si:H shows no IR absorption at 840--850 cm/sup -1/, which is consistent with the expected better thermal stability of the CVD material because of the much higher substrate temperatures in the CVD process than in the glow discharge process. (2) The band gap of CVD a-Si:H is lower by about 0.1 eV than glow discharge a-Si:H of the same hydrogen content. Thus, the band gap of CVD a-Si:H is better matched to the solar spectrum than is glow discharge a-Si:H. (3) All three IR absorption bands due to hydrogen are about 20% narrower in the CVD a-Si:H, suggesting a simpler structure. (4) The temperature dependence of the dark conductivity of CVD a-Si:H fits a curve for a single activation energy, in contrast to the more complicated temperature dependence often found in glow discharge a-Si:H, in which two different activation energies are seen at high and low temperatures. This suggests that the conduction mechanism is also simpler in the CVD a-Si:H.

Ellis, F.B. Jr.; Gordon, R.G.; Paul, W.; Yacobi, B.G.

1984-06-15T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Laser photochemical growth of amorphous silicon at low temperatures and comparison with thermal chemical vapor deposition  

SciTech Connect (OSTI)

Pulsed ArF (193 nm) excimer laser radiation has been used to dissociate disilane (Si/sub 2/H/sub 6/, resulting in photochemically controlled deposition of amorphous Si thin films. A high stability HeNe (6328 A) laser was used for precise in situ monitoring of film deposition rates, under varying deposition conditions. A helium window purge nearly eliminated Si film deposition on the chamber windows. With the excimer laser beam parallel to the substrate, deposition of amorphous Si can be controlled entirely by the photon fluence (negligible background thermal growth) at temperatures from room temperature up to /approximately/400/degree/C. Reasonable photolytic deposition rate (>1 A/sec) are combined with 'digital' control of film thickness (/approx gt/0.02 A/laser pulse). Activation energies of 1.50 (+-0.1) eV and 0.09 (+-0.02) eV were found for pyrolytic and photolytic deposition, respectively. 15 refs., 3 figs.

Eres, D.; Lowndes, D.H.; Geohegan, D.B.; Mashburn, D.N.

1987-01-01T23:59:59.000Z

282

Innovative Thin Films LLC | Open Energy Information  

Open Energy Info (EERE)

Thin Films LLC Thin Films LLC Jump to: navigation, search Name Innovative Thin Films LLC Place Toledo, Ohio Zip 43607 Product Provider of altnernative energy thin film deposition technology. Coordinates 46.440613°, -122.847838° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":46.440613,"lon":-122.847838,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

283

Spatial Frequency Filtering Using Nondelineated Thin Films  

Science Journals Connector (OSTI)

We present a new approach for achieving spatial frequency filtering in the analog domain. Our device, the Thin Film Spatial Filter, is a hybrid structure which combines the strengths of analog VLSI technology with the simplicity of a continuous sheet ...

J. Mcelvain; J. Langan; A. J. Heeger

1997-10-01T23:59:59.000Z

284

Visible spectrometer utilizing organic thin film absorption  

E-Print Network [OSTI]

In this thesis, I modeled and developed a spectrometer for the visible wavelength spectrum, based on absorption characteristics of organic thin films. The device uses fundamental principles of linear algebra to reconstruct ...

Tiefenbruck, Laura C. (Laura Christine)

2004-01-01T23:59:59.000Z

285

Hydrogen dynamics and light-induced structural changes in hydrogenated amorphous silicon T. A. Abtew* and D. A. Drabold  

E-Print Network [OSTI]

Hydrogen dynamics and light-induced structural changes in hydrogenated amorphous silicon T. A first-principles methods to study the network dynamics of hydrogenated amorphous silicon, including the motion of hydrogen. In addition to studies of atomic dynamics in the electronic ground state, we also

Drabold, David

286

Integrated thin film batteries on silicon  

E-Print Network [OSTI]

Monolithic integration has been implemented successfully in complementary metal oxide semiconductor (CMOS) technology and led to improved device performance, increased reliability, and overall cost reduction. The next ...

Ariel, Nava

2005-01-01T23:59:59.000Z

287

Experimental determination of the distribution of tail states of hydrogenated amorphous silicon: A transient photocurrent analysis  

SciTech Connect (OSTI)

Recent experimental developments have cast doubt on the validity of the common assumption that the distribution of tail states of hydrogenated amorphous silicon exhibits a single exponential functional form. The authors employ transient photocurrent decay measurements to determine this distribution of tail states. In their approach, however, they determine the distribution of tail states directly from the experimental data, without assuming, a priori, a specific functional form. It is found that these experimental results are consistent with other more recent experimental determinations of the distribution of tail states, suggesting the possibility of deviations from a single exponential distribution of tail states in hydrogenated amorphous silicon.

Webb, D.P.; Chan, F.Y.M.; Zou, X.C.; Chan, Y.C.; Lam, Y.W.; Lin, S.H.; O'Leary, S.K.; Lim, P.K.

1997-07-01T23:59:59.000Z

288

E-Print Network 3.0 - amorphous silicon detector Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Jacobs University Bremen Collection: Engineering ; Materials Science 26 Mechanics of thin-film transistors and solar cells on flexible substrates Helena Gleskova* Summary: be...

289

Crystal coherence length effects on the infrared optical response of MgO thin films.  

SciTech Connect (OSTI)

The role of crystal coherence length on the infrared optical response of MgO thin films was investigated with regard to Reststrahlen band photon-phonon coupling. Preferentially (001)-oriented sputtered and evaporated ion-beam assisted deposited thin films were prepared on silicon and annealed to vary film microstructure. Film crystalline coherence was characterized by x-ray diffraction line broadening and transmission electron microscopy. The infrared dielectric response revealed a strong dependence of dielectric resonance magnitude on crystalline coherence. Shifts to lower transverse optical phonon frequencies were observed with increased crystalline coherence. Increased optical phonon damping is attributed to increasing granularity and intergrain misorientation.

Boreman, Glenn D. (University of Central Florida, Orlando, FL); Kotula, Paul Gabriel; Rodriguez, Mark Andrew; Shelton, David J. (University of Central Florida, Orlando, FL); Carroll, James F., III; Sinclair, Michael B.; Ihlefeld, Jon F.; Ginn, James Cleveland, III; Clem, Paul Gilbert; Matias, Vladimir (Los Alamos National Laboratory, Los Alamos, NM)

2010-07-01T23:59:59.000Z

290

Crystal coherence length effects on the infrared optical response of MgO thin films  

SciTech Connect (OSTI)

The role of crystal coherence length on the infrared optical response of MgO thin films was investigated with regard to Reststrahlen band photon-phonon coupling. Preferentially (001)-oriented sputtered and evaporated ion-beam assisted deposited thin films were prepared on silicon and annealed to vary film microstructure. Film crystalline coherence was characterized by x-ray diffraction line broadening and transmission electron microscopy. The infrared dielectric response revealed a strong dependence of dielectric resonance magnitude on crystalline coherence. Shifts to lower transverse optical phonon frequencies were observed with increased crystalline coherence. Increased optical phonon damping is attributed to increasing granularity and intergrain misorientation.

Ihlefeld, J. F.; Ginn, J. C.; Rodriguez, M. A.; Kotula, P. G.; Carroll, J. F. III; Clem, P. G.; Sinclair, M. B. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Shelton, D. J.; Boreman, G. D. [College of Optics and Photonics/CREOL, University of Central Florida, Orlando, Florida 32816 (United States); Matias, V. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2010-11-08T23:59:59.000Z

291

Electron Injection Mechanism in Top-gate Amorphous Silicon Thin-film Transistors with Self-Aligned Silicide Source and Drain  

E-Print Network [OSTI]

Institute for the Science and Technology of Materials (PRISM), Department of Elect. Eng., Princeton. The devices exhibit a threshold voltage of 2.7V, saturation mobility of 1cm2 /Vs, subthreshold slope of 600m from 1cm2 /Vs at L=100µm to 0.65 cm2 /Vs at L=5µm while the observed effective threshold is independent

292

Passivation effect on gate-bias stress instability of carbon nanotube thin film transistors  

SciTech Connect (OSTI)

A prior requirement of any developed transistor for practical use is the stability test. Random network carbon nanotube-thin film transistor (CNT-TFT) was fabricated on SiO{sub 2}/Si. Gate bias stress stability was investigated with various passivation layers of HfO{sub 2} and Al{sub 2}O{sub 3}. Compared to the threshold voltage shift without passivation layer, the measured values in the presence of passivation layers were reduced independent of gate bias polarity except HfO{sub 2} under positive gate bias stress (PGBS). Al{sub 2}O{sub 3} capping layer was found to be the best passivation layer to prevent ambient gas adsorption, while gas adsorption on HfO{sub 2} layer was unavoidable, inducing surface charges to increase threshold voltage shift in particular for PGBS. This high performance in the gate bias stress test of CNT-TFT even superior to that of amorphous silicon opens potential applications to active TFT industry for soft electronics.

Won Lee, Sang [Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Suh, Dongseok, E-mail: energy.suh@skku.edu [Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Department of Energy Science and Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Young Lee, Si [Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Department of Physics, Sungkyunkwan Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Hee Lee, Young, E-mail: leeyoung@skku.edu [Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Department of Energy Science and Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Department of Physics, Sungkyunkwan Advanced Institute of Nanotechnology, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

2014-04-21T23:59:59.000Z

293

Numerical simulation of the heat transfer in amorphous silicon nitride membrane-based microcalorimeters  

E-Print Network [OSTI]

Numerical simulation of the heat transfer in amorphous silicon nitride membrane July 2003 Numerical simulations of the two-dimensional 2D heat flow in a membrane-based microcalorimeter have been performed. The steady-state isotherms and time-dependent heat flow have been calculated

Hellman, Frances

294

Short Channel Amorphous-Silicon TFT's on High-Temperature Clear Plastic Substrates  

E-Print Network [OSTI]

Short Channel Amorphous-Silicon TFT's on High-Temperature Clear Plastic Substrates K. Long, H@princeton.edu To achieve light-weight flexible AMOLED displays on plastic substrates, the substratesmust be optically clear for plastic. High-temperature plastics such as polyimide (e.g. KaptonB E) have a glass transition temperature

295

Exciton splitting and carrier transport across the amorphous-silicon/ polymer solar cell interface  

E-Print Network [OSTI]

of bilayer hybrid solar cells to better understand the physics controlling organic-inorganic device of Physics. DOI: 10.1063/1.2408641 Hybrid organic-inorganic solar cells combine the pro- cessabilityExciton splitting and carrier transport across the amorphous-silicon/ polymer solar cell interface

McGehee, Michael

296

High Efficiency and High Rate Deposited Amorphous Silicon-Based Solar Cells  

E-Print Network [OSTI]

. Figure 3-1 IV curve of a UT fabricated triple cell, showing 12.7% initial, active-area efficiency. Figure1 High Efficiency and High Rate Deposited Amorphous Silicon-Based Solar Cells PHASE I Annual-junction a-Si Solar Cells with Heavily Doped Thin Interface Layers at the Tunnel Junctions Section 4 High

Deng, Xunming

297

Thin film absorber for a solar collector  

DOE Patents [OSTI]

This invention pertains to energy absorbers for solar collectors, and more particularly to high performance thin film absorbers. The solar collectors comprising the absorber of this invention overcome several problems seen in current systems, such as excessive hardware, high cost and unreliability. In the preferred form, the apparatus features a substantially rigid planar frame with a thin film window bonded to one planar side of the frame. An absorber in accordance with the present invention is comprised of two thin film layers that are sealed perimetrically. In a preferred embodiment, thin film layers are formed from a metal/plastic laminate. The layers define a fluid-tight planar envelope of large surface area to volume through which a heat transfer fluid flows. The absorber is bonded to the other planar side of the frame. The thin film construction of the absorber assures substantially full envelope wetting and thus good efficiency. The window and absorber films stress the frame adding to the overall strength of the collector.

Wilhelm, William G. (Cutchogue, NY)

1985-01-01T23:59:59.000Z

298

Recrystallization of amorphous silicon deposited on ultra thin microcrystalline silicon layers  

SciTech Connect (OSTI)

This study reports on a method to reduce the thermal crystallization time and temperature of amorphous silicon films by initially depositing an ultra thin {micro}c-Si:H seed layer. After rapid thermal annealing (RTA), films were characterized by means of Raman spectroscopy, x-ray diffraction, reflection high energy electron diffraction, atomic force microscopy, and dark and photocurrent. The results show that the microcrystalline particles in the seed layer act as nucleation centers, promoting crystallization of a-Si:H at lower temperatures and at shorter times, compared to a-Si:H films deposited without any seed layer. Additionally, it was found that the seed layer affects the orientation of the crystallized films. The dark current increases abruptly over 4 orders of magnitude in the first 15 second anneal, then decreases as the time increases, and tends to saturate. The photocurrent has an opposite behavior. These transport results can be understood in terms of a change in defect density and band gap shrinkage.

Wang, F.; Wolfe, D.; Lucovsky, G.

1997-07-01T23:59:59.000Z

299

Thin film transistors on plastic substrates with reflective coatings for radiation protection  

DOE Patents [OSTI]

Fabrication of silicon thin film transistors (TFT) on low-temperature plastic substrates using a reflective coating so that inexpensive plastic substrates may be used in place of standard glass, quartz, and silicon wafer-based substrates. The TFT can be used in large area low cost electronics, such as flat panel displays and portable electronics such as video cameras, personal digital assistants, and cell phones.

Wolfe, Jesse D. (Fairfield, CA); Theiss, Steven D. (Woodbury, MN); Carey, Paul G. (Mountain View, CA); Smith, Patrick M. (San Ramon, CA); Wickbold, Paul (Walnut Creek, CA)

2006-09-26T23:59:59.000Z

300

Low-Cost Label-Free Electrical Detection of Artificial DNA Nanostructures Using Solution-Processed Oxide Thin-Film Transistors  

Science Journals Connector (OSTI)

As stabilizers, monoethanolamine (MEA) and acetic acid (CH3COOH) were dropped to ameliorate the solubility of the precursors and make a homogeneous IGZO solution, respectively. ... Prepared DNA-covered mica sheet was attached onto the metal puck using instant glue and 5 ?L of DX solution, 30 ?L of 1 × TAE/Mg2+ buffer was dropped onto the mica and 10 ?L of 1 × TAE/Mg2+ buffer was mounted onto the AFM tip (A NP-S oxide-sharpened silicon nitride tip). ... The original influence of water on the back-channel of sol-gel derived amorphous indium-gallium-zinc-oxide thin film transistors was studied in various relative humidity environments. ...

Si Joon Kim; Joohye Jung; Keun Woo Lee; Doo Hyun Yoon; Tae Soo Jung; Sreekantha Reddy Dugasani; Sung Ha Park; Hyun Jae Kim

2013-09-27T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Crystalline Silicon under Acoustic Cavitation: From Mechanoluminescence to Amorphization  

Science Journals Connector (OSTI)

The physicochemical behavior of crystalline silicon under acoustic cavitation is investigated in water sparged with argon at low temperature (10 and 20 °C). Surprisingly, spectroscopic investigations reveal that argon (bubbling continuously through the ...

Matthieu Virot; Rachel Pflieger; Ekaterina V. Skorb; Johann Ravaux; Thomas Zemb; Helmuth Möhwald

2012-06-21T23:59:59.000Z

302

Superhydrophobic Thin Film Symposium | ornl.gov  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Superhydrophobic Thin Film Symposium Superhydrophobic Thin Film Symposium Sep 05 2012 12:00 AM - 05:00 PM Hosted by Oak Ridge Laboratory's Partnerships Directorate and focusing on the recent LDRD Launch project work completed by Dr. Tolga Aytug and Dr. John T. Simpson (ORNL research PI's). Oak Ridge, TN Oak Ridge National Laboratory CONTACT : Email: Cassie Lopez Phone:(865) 576-9294 Add to Calendar SHARE Hosted by Oak Ridge Laboratory's Partnerships Directorate and focusing on the recent LDRD Launch project work completed by Dr. Tolga Aytug and Dr. John T. Simpson (ORNL research PI's). Purpose To share the ORNL Superhydrophonbic Thin Film technology to prospective commercial partners. Date and Time The conference will be held on the morning of Wednesday September 5th at Oak Ridge National Laboratory (ORNL) by Partnerships and Technology

303

Vibration welding system with thin film sensor  

DOE Patents [OSTI]

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

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

2014-03-18T23:59:59.000Z

304

Superlattice-like Ge8Sb92/Ge thin films for high speed and low power consumption phase change memory application  

Science Journals Connector (OSTI)

The amorphous-to-crystalline transitions of superlattice-like Ge8Sb92/Ge thin films were investigated through in situ film resistance measurement. X-ray reflectivity was used to measure the density change before and after phase change. The superlattice-like structure of the thin films was confirmed by using transmission electron microscopy. A picosecond laser pump–probe system was used to study the phase change speed. Phase change memory cells based on the SLL [Ge8Sb92(4 nm)/Ge(3 nm)]7 thin films were fabricated to test and verify the switching speed and operation consumption.

Yifeng Hu; Xiaoyi Feng; Jiwei Zhai; Ting Wen; Tianshu Lai; Sannian Song; Zhitang Song

2014-01-01T23:59:59.000Z

305

SAW determination of surface area of thin films  

DOE Patents [OSTI]

N.sub.2 adsorption isotherms are measured from thin films on SAW devices. The isotherms may be used to determine the surface area and pore size distribution of thin films.

Frye, Gregory C. (Albuquerque, NM); Martin, Stephen J. (Albuquerque, NM); Ricco, Antonio J. (Albuquerque, NM)

1990-01-01T23:59:59.000Z

306

Conductivity of Oriented Samaria-Doped Ceria Thin Films Grown...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Conductivity of Oriented Samaria-Doped Ceria Thin Films Grown by Oxygen-plasma-assisted Molecular Beam Epitaxy. Conductivity of Oriented Samaria-Doped Ceria Thin Films Grown by...

307

Chemical vapor deposition of amorphous semiconductor films. Final subcontract report  

SciTech Connect (OSTI)

Chemical vapor deposition (CVD) from higher order silanes has been studied for fabricating amorphous hydrogenated silicon thin-film solar cells. Intrinsic and doped a-Si:H films were deposited in a reduced-pressure, tubular-flow reactor, using disilane feed-gas. Conditions for depositing intrinsic films at growth rates up to 10 A/s were identified. Electrical and optical properties, including dark conductivity, photoconductivity, activation energy, optical absorption, band-gap and sub-band-gap absorption properties of CVD intrinsic material were characterized. Parameter space for depositing intrinsic and doped films, suitable for device analysis, was identified.

Rocheleau, R.E.

1984-12-01T23:59:59.000Z

308

Novel silane and disilane precursors to amorphous semiconductors: Final subcontract report, May 1988  

SciTech Connect (OSTI)

This Final Report describes the preparation and characterization of amorphous fluorohydrogenated silicon thin films. The novel approach in this study lies in the use of fluorinated silanes as film precursors. The advantages of this method are well defined initial ratios of hydrogen and fluorine to silicon and greatly reduced hazards in the handling of the gas. Fluorine derivatives of both silane and disilane were synthesized. Both glow discharge (or plasma-enhanced CVD) and thermal (CVD) methods were employed to prepare amorphous silicon on glass and silicon wafers. The electrical characterization of the material prepared from difluorosilane showed that the a-Si:H:F films obtained are of solar-grade semiconductor quality and can be doped to p- and n-type materials with diborane and phosphine. 29 refs., 24 figs., 10 tabs.

Pernisz, U.C.; Sharp, K.G.

1988-09-01T23:59:59.000Z

309

SINGLE AND DUAL LAYER THIN FILM BULGE TESTING  

E-Print Network [OSTI]

film windows that are used in Next Generation Lithography masks and certain MEMS devices. The bulge testing method measures the mechanical properties of a thin film by isolating it in a thin film window of the system. Figure 6 Dual Layer Thin Film Membrane Window For a dual layer membrane the effective total

Huston, Dryver R.

310

THIN FILM MECHANICS BULGING AND Ph.D Dissertation  

E-Print Network [OSTI]

for the intensive effort in research in materials and processing techniques. Thin film windows are window underneath. The thin film window has such a small thickness to span ratio that it can usually be considered and precision-stretching of thin film windows are examined. Bulge Testing is a method used to evaluate

Huston, Dryver R.

311

Template structure at the silicon/amorphous-silicide interface  

SciTech Connect (OSTI)

Surface x-ray diffraction was used to monitor the reaction of Ni on Si(111) at room temperature. Intensity oscillations during deposition signify that a layerwise reaction occurs for the first 30 A of metal deposited, forming a silicide overlayer with stoichiometry Ni{sub 2}Si. Structural analysis of the interfacial layers detects an epitaxial and commensurate phase, Ni{sub 2}Si-{theta}, with long range order imposed by the substrate but with very large local atomic displacements. This epitaxial structure remains at the interface as amorphous silicide forms above it.

Bennett, P.A.; Lee, M.Y.; Yang, P. [Department of Physics and Astronomy, Arizona State University, Box 871504, Tempe, Arizona 85287-1504 (United States)] [Department of Physics and Astronomy, Arizona State University, Box 871504, Tempe, Arizona 85287-1504 (United States); Schuster, R.; Eng, P.J.; Robinson, I.K. [Physics Department, University of Illinois, Urbana, Illinois 61801 (United States)] [Physics Department, University of Illinois, Urbana, Illinois 61801 (United States)

1995-10-02T23:59:59.000Z

312

Thin films for solar control applications  

Science Journals Connector (OSTI)

...properly cited. Thin films for solar control applications Sapna Shrestha...performance of vacuum glazing. Solar Energy 81, 8. ( doi:10...mirrors produced by plasma ion assisted deposition. J. Non-Cryst...and cost of vacuum glazing. Solar Energy 55, 151. ( doi:10...

2010-01-01T23:59:59.000Z

313

Enhanced Thin Film Organic Photovoltaic Devices  

Energy Innovation Portal (Marketing Summaries) [EERE]

A novel structure design for thin film organic photovoltaic (OPV) devices provides a system for increasing the optical absorption in the active layer. The waveguided structure permits reduction of the active layer thickness, resulting in enhanced charge collection and extraction, leading to improved power conversion efficiency compared to standard OPV devices....

2014-01-10T23:59:59.000Z

314

Determination of hydrogen density of states in amorphous silicon using fractional evolution experiments  

SciTech Connect (OSTI)

Hydrogen plays an important role in the electronic behavior, structure and stability of amorphous silicon films. Therefore, determination of the hydrogen density of states (DOS) and correlation of the hydrogen DOS with the electronic film properties are important research goals. The authors have developed a novel method for determination of hydrogen DOS in silicon films, based on fractional evolution experiments. Fractional evolution experiments are performed by subjecting a silicon film to a series of linear, alternating heating and cooling ramps, while monitoring the hydrogen evolution rate. The fractional evolution data can be analyzed using two complementary methods, the fixed frequency factor approach and Arrhenius analysis. Using a rigorous, mean-field evolution model, they demonstrate the applicability of the two approaches to obtaining the hydrogen DOS in silicon films. They further validate both methods by analyzing experimental fractional evolution data for an amorphous silicon carbide film. Both types of analysis yield a similar double peaked density of states for the a-Si:C:H:D film.

Franz, A.J.; Jackson, W.B.; Gland, J.L.

1997-07-01T23:59:59.000Z

315

Research Progress in the DOE/SERI Amorphous Silicon Research Project  

SciTech Connect (OSTI)

The Amorphous Silicon Research Project (ASRP), established at the Solar Energy Research Institute (SERI) in 1983, is responsible for all U.S. DOE government-supported research activities in the field of amorphous silicon photovoltaics. The objectives and research directions of the project have been established by a Five-Year Research Plan developed at SERI in cooperation with the Department of Energy in 1984. In order to accomplish project goals, research is performed by a combination of i) multi-year programs consisting of multi-disciplinary research teams based on strong government/industry partnerships and ii) basic research performed in university, government, and industrial laboratories. A summary of recent research progress in the ASRP program is presented.

Sabisky, E.; Wallace, W.; Stafford, B.; Sadlon, K.; Luft, W.

1985-04-01T23:59:59.000Z

316

Growth of Hydrogenated Amorphous Silicon Films by ArF Excimer Laser Photodissociation of Disilane  

Science Journals Connector (OSTI)

Hydrogenated amorphous silicon films have been grown on glass substrates by photodissociation of disilane using a pulsed ArF excimer laser foe the first time. Electrical and optical properties of the films have been examined. It was found that the magnitude of the gap energy of laser CVD films is rather large as compared to that of films obtained by a conventional plasma CVD. Preliminary examinations to control the conductivity by impurity doping have also been performed.

Akihiko Yoshikawa; Shigeki Yamaga

1984-01-01T23:59:59.000Z

317

Photocapacitance and hole drift mobility measurements in hydrogenated amorphous silicon (a-Si:H)  

SciTech Connect (OSTI)

The authors present measurements of the photocapacitance in hydrogenated amorphous silicon (a-Si:H) Schottky barrier diodes under reverse bias. A calculation relating photocapacitance to hole drift mobility measurements is also presented; the calculation incorporates the prominent dispersion effect for holes in a-Si:H usually attributed to valence bandtail trapping. The calculation accounts quantitatively for the magnitude and voltage-dependence of the photocapacitance.

Nurdjaja, I.; Schiff, E.A.

1997-07-01T23:59:59.000Z

318

High electric field effects on the thermal generation in hydrogenated amorphous silicon  

SciTech Connect (OSTI)

The authors have studied the electric field dependence of the electron-hole thermal generation process in hydrogenated amorphous silicon. A model was developed which takes into account the Poole-Frenkel effect and the thermally assisted tunneling. In order to explain the experimental results it was necessary to consider a strong electron-lattice interaction describing the carrier tunneling mechanism. Deep defects relaxation is also discussed.

Ilie, A.; Equer, B.

1997-07-01T23:59:59.000Z

319

Fluctuating defect density probed with noise spectroscopy in hydrogenated amorphous silicon  

SciTech Connect (OSTI)

Resistance fluctuations have been studied in hydrogenated amorphous silicon in the temperature range between 300 K and 450 K. The primary noise source has a power spectrum of approximately 1/f and is ascribed to hydrogen motion. Hopping of weakly bound hydrogen is thermally activated at such low temperatures with an average activation energy of 0.85 eV. The attempt rate amounts to 7 {center_dot} 10{sup 12} s{sup {minus}1}.

Verleg, P.A.W.E.; Uca, O.; Dijkhuis, J.I.

1997-07-01T23:59:59.000Z

320

Transient photoconductivity studies of the light soaked state of hydrogenated amorphous silicon  

Science Journals Connector (OSTI)

Studies of transient photoconductivity show that the primary effect of light soaking in hydrogenated amorphous silicon is to introduce dangling bonds of bulk density 101 6–101 7 cm? 3. Light soaking reduces the ?? product of both electrons and holes to values which are quantitatively related to the observed increase in the dangling bondelectron spin resonance(ESR) spin density. In addition no change in the carrier drift mobilities is detected after light soaking.

R. A. Street

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Thermally?induced instabilities and the Staebler?Wronski effect in doped amorphous silicon  

Science Journals Connector (OSTI)

The quenched?in excess conductivity which results from the thermal equilibrium of the defect structure in doped hydrogenated amorphous silicon is compared to the Staebler?Wronski effect. Exposure to light or cooling below the equlibration temperature induces a metastable state described by the thermal equlibrium model. The time dependence of the relaxation of these metastable states is interpreted in terms of the hydrogen glass model.

J. Kakalios; R. A. Street

1987-01-01T23:59:59.000Z

322

Dual operation characteristics of resistance random access memory in indium-gallium-zinc-oxide thin film transistors  

SciTech Connect (OSTI)

In this study, indium-gallium-zinc-oxide thin film transistors can be operated either as transistors or resistance random access memory devices. Before the forming process, current-voltage curve transfer characteristics are observed, and resistance switching characteristics are measured after a forming process. These resistance switching characteristics exhibit two behaviors, and are dominated by different mechanisms. The mode 1 resistance switching behavior is due to oxygen vacancies, while mode 2 is dominated by the formation of an oxygen-rich layer. Furthermore, an easy approach is proposed to reduce power consumption when using these resistance random access memory devices with the amorphous indium-gallium-zinc-oxide thin film transistor.

Yang, Jyun-Bao; Chen, Yu-Ting; Chu, Ann-Kuo [Department of Photonics, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Chang, Ting-Chang, E-mail: tcchang@mail.phys.nsysu.edu.tw [Department of Photonics, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Department of Physics, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Advanced Optoelectronics Technology Center, National Cheng Kung University, Taiwan (China); Huang, Jheng-Jie; Chen, Yu-Chun; Tseng, Hsueh-Chih [Department of Physics, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Sze, Simon M. [Department of Physics, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Department of Electronics Engineering, National Chiao Tung University, Hsinchu, Taiwan (China)

2014-04-14T23:59:59.000Z

323

Diagnostics of a glow discharge used to produce hydrogenated amorphous silicon films. Final subcontract report  

SciTech Connect (OSTI)

This report and recent publications cited summarize our measurements of the neutral radicals produced in pure silane discharges, our measurements of the interaction of silane with a growing amorphous silicon surface, qualitative models of discharge neutral radical chemistry, and quantitative models of dc discharge ion chemistry. All radicals of the monosilane and disilane groups have been measured and are reported as a function of discharge parameters, but not yet for the full range of parameters that must be investigated for detailed analysis. Observations of the reaction of SiH/sub 4/ with a hot amorphous silicon surface are given. These are closely related to the dominant discharge film deposition mechanism of SiH/sub 3/ reacting with a hydrogen covered amorphous silicon surface and a surface reaction model is suggested that explains some but not all of our data. The dc discharge model is used to obtain quantitative predictions of the ion species at the cathode surface of a dc discharge. This is compared to observations and used to explain the observations at our laboratory and other laboratories. We conclude that most but not all features of the ion chemistry in dc discharges of pure silane can be relatively well understood from this model.

Gallagher, A.

1984-11-01T23:59:59.000Z

324

Oriented niobate ferroelectric thin films for electrical and optical devices and method of making such films  

DOE Patents [OSTI]

Sr{sub x}Ba{sub 1{minus}x}Nb{sub 2}O{sub 6}, where x is greater than 0.25 and less than 0.75, and KNbO{sub 3} ferroelectric thin films metalorganic chemical vapor deposited on amorphous or crystalline substrate surfaces to provide a crystal axis of the film exhibiting a high dielectric susceptibility, electro-optic coefficient, and/or nonlinear optic coefficient oriented preferentially in a direction relative to a crystalline or amorphous substrate surface are disclosed. Such films can be used in electronic, electro-optic, and frequency doubling components. 8 figs.

Wessels, B.W.; Nystrom, M.J.

1998-05-19T23:59:59.000Z

325

Oriented niobate ferroelectric thin films for electrical and optical devices and method of making such films  

DOE Patents [OSTI]

Sr.sub.x Ba.sub.1-x Nb.sub.2 O.sub.6, where x is greater than 0.25 and less than 0.75, and KNbO.sub.3 ferroelectric thin films metalorganic chemical vapor deposited on amorphous or crystalline substrate surfaces to provide a crystal axis of the film exhibiting a high dielectric susceptibility, electro-optic coefficient, and/or nonlinear optic coefficient oriented preferentially in a direction relative to a crystalline or amorphous substrate surface. Such films can be used in electronic, electro-optic, and frequency doubling components.

Wessels, Bruce W. (Wilmette, IL); Nystrom, Michael J. (Germantown, MD)

1998-01-01T23:59:59.000Z

326

Optimization of transparent and reflecting electrodes for amorphous silicon solar cells. Final technical report  

SciTech Connect (OSTI)

Transparent conducting fluorine doped zinc oxide was deposited as thin films on soda lime glass substrates by atmospheric pressure chemical vapor deposition (CVD) at substrate temperatures of 460 to 500 degrees C. The precursors diethylzinc, tetramethylethylenediamine and benzoyl fluoride were dissolved in xylene. This solution was nebulized ultrasonically and then flash vaporized by a carrier gas of nitrogen preheated to 150 degrees C. Ethanol was vaporized separately, and these vapors were then mixed to form a homogeneous vapor mixture. Good reproducibility was achieved using this new CVD method. Uniform thicknesses were obtained by moving the heated glass substrates through the deposition zone. The best electrically and optical properties were obtained when the precursor solution was aged for more than a week before use. The films were polycrystalline and highly oriented with the c-axis perpendicular to the substrate. More than 90% of the incorporated fluorine atoms were electrically active as n-type dopants. The electrical resistivity of the films was as low as 5 x 10/sup -4/ Omega cm. The mobility was about 45 cm ²/Vs. The electron concentration was up to 3 x 10 %sup20;/cm³. The optical absorption of the films was about 3-4% at a sheet resistance of 7 ohms/square. The diffuse transmittance was about 10% at a wavelength of 650 nm. Amorphous ilicon solar cells were deposited using the textured fluorine doped zinc oxide films as a front electrode. The short circuit current was increased over similar cells made with fluorine doped tin oxide, but the open circuit voltages and fill factors were reduced. The voltage was restored by overcoating the fluorine-doped zinc oxide with a thin layer of fluorine-doped tin oxide.

Gordon, R.G.; Kramer, K.; Liang, H.; Liu, X.; Pang, D.; Teff, D.

1998-09-01T23:59:59.000Z

327

Surface modification of a \\{WTi\\} thin film on Si substrate by nanosecond laser pulses  

Science Journals Connector (OSTI)

Interaction of a nanosecond transversely excited atmospheric (TEA) CO2 laser, operating at 10.6 ?m, with tungsten–titanium thin film (190 nm) deposited on silicon of n-type (1 0 0) orientation, was studied. Multi-pulse irradiation was performed in air atmosphere with laser energy densities in the range 24–49 J/cm2. The energy absorbed from the laser beam was mainly converted to thermal energy, which generated a series of effects. The following morphological changes were observed: (i) partial ablation/exfoliation of the \\{WTi\\} thin film, (ii) partial modification of the silicon substrate with formation of polygonal grains, (iii) appearance of hydrodynamic features including nano-globules. Torch-like plumes started appearing in front of the target after several laser pulses.

S. Petrovi?; B. Gakovi?; D. Peruško; M. Trtica; B. Radak; P. Panjan; Š. Miljani?

2008-01-01T23:59:59.000Z

328

Nanocrystalline Silicon Quantum Dot Light Emitting Diodes Using Metal Oxide Charge Transport Layers.  

E-Print Network [OSTI]

??Silicon-based lighting show promise for display and solid state lighting use. Here we demonstrate a novel thin film light emitting diode device using nanocrystalline silicon… (more)

Zhu, Jiayuan

2013-01-01T23:59:59.000Z

329

Hard TiCx/SiC/a-C:H nanocomposite thin films using pulsed high energy density plasma focus device  

Science Journals Connector (OSTI)

Abstract Thin films of TiCx/SiC/a-C:H were synthesized on Si substrates using a complex mix of high energy density plasmas and instability accelerated energetic ions of filling gas species, emanated from hot and dense pinched plasma column, in dense plasma focus device. The conventional hollow copper anode of Mather type plasma focus device was replaced by solid titanium anode for synthesis of TiCx/SiC/a-C:H nanocomposite thin films using CH4:Ar admixture of (1:9, 3:7 and 5:5) for fixed 20 focus shots as well as with different number of focus shots with fixed CH4:Ar admixture ratio 3:7. XRD results showed the formation of crystalline TiCx/SiC phases for thin film synthesized using different number of focus shots with CH4:Ar admixture ratio fixed at 3:7. SEM results showed that the synthesized thin films consist of nanoparticle agglomerates and the size of agglomerates depended on the CH4:Ar admixture ratio as well as on the number of focus shots. Raman analysis showed the formation of polycrystalline/amorphous Si, SiC and a-C for different CH4:Ar ratio as well as for different number of focus shots. The XPS analysis confirmed the formation of TiCx/SiC/a-C:H composite thin film. Nanoindentation results showed that the hardness and elastic modulus values of composite thin films increased with increasing number of focus shots. Maximum values of hardness and elastic modulus at the surface of the composite thin film were found to be about 22 and 305 GPa, respectively for 30 focus shots confirming the successful synthesis of hard composite TiCx/SiC/a-C:H coatings.

Z.A. Umar; R.S. Rawat; K.S. Tan; A.K. Kumar; R. Ahmad; T. Hussain; C. Kloc; Z. Chen; L. Shen; Z. Zhang

2013-01-01T23:59:59.000Z

330

Anisotropic dewetting in ultra-thin single-crystal silicon-on-insulator films  

E-Print Network [OSTI]

The single crystal silicon-on-insulator thin film materials system represents both an ideal model system for the study of anisotropic thin film dewetting as well as a technologically important system for the development ...

Danielson, David T. (David Thomas)

2008-01-01T23:59:59.000Z

331

Thin film photovoltaic panel and method  

DOE Patents [OSTI]

A thin film photovoltaic panel includes a backcap for protecting the active components of the photovoltaic cells from adverse environmental elements. A spacing between the backcap and a top electrode layer is preferably filled with a desiccant to further reduce water vapor contamination of the environment surrounding the photovoltaic cells. The contamination of the spacing between the backcap and the cells may be further reduced by passing a selected gas through the spacing subsequent to sealing the backcap to the base of the photovoltaic panels, and once purged this spacing may be filled with an inert gas. The techniques of the present invention are preferably applied to thin film photovoltaic panels each formed from a plurality of photovoltaic cells arranged on a vitreous substrate. The stability of photovoltaic conversion efficiency remains relatively high during the life of the photovoltaic panel, and the cost of manufacturing highly efficient panels with such improved stability is significantly reduced.

Ackerman, Bruce (El Paso, TX); Albright, Scot P. (El Paso, TX); Jordan, John F. (El Paso, TX)

1991-06-11T23:59:59.000Z

332

Annealed CVD molybdenum thin film surface  

DOE Patents [OSTI]

Molybdenum thin films deposited by pyrolytic decomposition of Mo(CO).sub.6 attain, after anneal in a reducing atmosphere at temperatures greater than 700.degree. C., infrared reflectance values greater than reflectance of supersmooth bulk molybdenum. Black molybdenum films deposited under oxidizing conditions and annealed, when covered with an anti-reflecting coating, approach the ideal solar collector characteristic of visible light absorber and infrared energy reflector.

Carver, Gary E. (Tucson, AZ); Seraphin, Bernhard O. (Tucson, AZ)

1984-01-01T23:59:59.000Z

333

From: Amorphous & Microcrystalline Silicon Technology, edited by S. Wagner, M. Hack, E. A. Schiff, R. Schropp, and I. Shimizu (Materials Research Society Symposium Proceedings, Vol.  

E-Print Network [OSTI]

From: Amorphous & Microcrystalline Silicon Technology, edited by S. Wagner, M. Hack, E. A. Schiff & Microcrystalline Silicon Technology, edited by S. Wagner, M. Hack, E. A. Schiff, R. Schropp, and I. Shimizu

Schiff, Eric A.

334

Fabrication Of Multilayered Thin Films Via Spin-Assembly  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Fabrication Of Multilayered Thin Films Via Spin-Assembly Fabrication Of Multilayered Thin Films Via Spin-Assembly Fabrication Of Multilayered Thin Films Via Spin-Assembly A process of forming multilayer thin film heterostructures. Available for thumbnail of Feynman Center (505) 665-9090 Email Fabrication Of Multilayered Thin Films Via Spin-Assembly A process of forming multilayer thin film heterostructures is disclosed and includes applying a solution including a first water-soluble polymer from the group of polyanionic species, polycationic species and uncharged polymer species onto a substrate to form a first coating layer on the substrate, drying the first coating layer on the substrate, applying a solution including a second water-soluble polymer from the group of polyanionic species, polycationic species and uncharged polymer species

335

Nitrogen Diffusion in Amorphous Silicon Nitride Isotope Multilayers Probed by Neutron Reflectometry  

Science Journals Connector (OSTI)

Amorphous silicon nitride is a model system for a covalently bound amorphous solid with a low atomic mobility where reasonable values of self-diffusivities are still lacking. We used neutron reflectometry on isotope enriched Si3?N414/Si3?N415 multilayers to determine nitrogen self-diffusivities ranging from 10-24 to 10-21??m2/s between 950 and 1250?°C. Time dependent diffusivities observed at 1150?°C indicate the presence of structural relaxation. For long annealing times (relaxed state) the diffusivities follow an Arrhenius law with an activation enthalpy of (3.6±0.4)??eV. The results are indicative of a direct diffusion mechanism without the involvement of thermal point defects.

H. Schmidt; M. Gupta; M. Bruns

2006-02-07T23:59:59.000Z

336

Nitrogen Diffusion in Amorphous Silicon Nitride Isotope Multilayers Probed by Neutron Reflectometry  

SciTech Connect (OSTI)

Amorphous silicon nitride is a model system for a covalently bound amorphous solid with a low atomic mobility where reasonable values of self-diffusivities are still lacking. We used neutron reflectometry on isotope enriched Si{sub 3} {sup 14}N{sub 4}/Si{sub 3} {sup 15}N{sub 4} multilayers to determine nitrogen self-diffusivities ranging from 10{sup -24} to 10{sup -21} m{sup 2}/s between 950 and 1250 deg. C. Time dependent diffusivities observed at 1150 deg. C indicate the presence of structural relaxation. For long annealing times (relaxed state) the diffusivities follow an Arrhenius law with an activation enthalpy of (3.6{+-}0.4) eV. The results are indicative of a direct diffusion mechanism without the involvement of thermal point defects.

Schmidt, H.; Gupta, M.; Bruns, M. [AG Thermochemie und Mikrokinetik, Fakultaet fuer Natur-und Materialwissenschaften, TU Clausthal, D-38678 Clausthal-Zellerfeld (Germany); Laboratory for Neutron Scattering, ETH Zuerich and PSI, Paul Scherrer Institute, Villigen, CH-5232 (Switzerland); Institut fuer Instrumentelle Analytik, Forschungszentrum Karlsruhe GmbH, D-76021 Karlsruhe (Germany)

2006-02-10T23:59:59.000Z

337

.beta.-silicon carbide protective coating and method for fabricating same  

DOE Patents [OSTI]

A polycrystalline beta-silicon carbide film or coating and method for forming same on components, such as the top of solar cells, to act as an extremely hard protective surface, and as an anti-reflective coating. This is achieved by DC magnetron co-sputtering of amorphous silicon and carbon to form a SiC thin film onto a surface, such as a solar cell. The thin film is then irradiated by a pulsed energy source, such as an excimer laser, to synthesize the poly- or .mu.c-SiC film on the surface and produce .beta.--SiC. While the method of this invention has primary application in solar cell manufacturing, it has application wherever there is a requirement for an extremely hard surface.

Carey, Paul G. (Mountain View, CA); Thompson, Jesse B. (Brentwood, CA)

1994-01-01T23:59:59.000Z

338

[beta]-silicon carbide protective coating and method for fabricating same  

DOE Patents [OSTI]

A polycrystalline beta-silicon carbide film or coating and method for forming same on components, such as the top of solar cells, to act as an extremely hard protective surface, and as an anti-reflective coating are disclosed. This is achieved by DC magnetron co-sputtering of amorphous silicon and carbon to form a SiC thin film onto a surface, such as a solar cell. The thin film is then irradiated by a pulsed energy source, such as an excimer laser, to synthesize the poly- or [mu]c-SiC film on the surface and produce [beta]-SiC. While the method of this invention has primary application in solar cell manufacturing, it has application wherever there is a requirement for an extremely hard surface. 3 figs.

Carey, P.G.; Thompson, J.B.

1994-11-01T23:59:59.000Z

339

Optical properties of nanostructured silicon-rich silicon dioxide  

E-Print Network [OSTI]

We have conducted a study of the optical properties of sputtered silicon-rich silicon dioxide (SRO) thin films with specific application for the fabrication of erbium-doped waveguide amplifiers and lasers, polarization ...

Stolfi, Michael Anthony

2006-01-01T23:59:59.000Z

340

Nanoarrays for Light Management in Thin Film Solar Cells  

Science Journals Connector (OSTI)

We report the use of plasmonic and photonic nanoarray to achieve light management in thin film solar cells. Theoretical and experimental data will be presented.

Ji, Jin; Nasr, Magued B; McCutcheon, Murray W; Herring, Cy

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Apparatus and Method for Fabricating Thin Film Devices using...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

method for manufacturing thin-films was developed specifically for fabrication of CdSCdTe photovoltaic modules. However, this innovation should perform excellently for any...

342

Creating CZTS Thin Films Via Stacked Metallic CVD and Sulfurization  

E-Print Network [OSTI]

Research, Thin-Film Photovoltaic (PV) Cells Market Analysiscost of photovoltaic systems (such as solar cells) due tosolar cells are created by depositing layers of photovoltaic

Bielecki, Anthony

2013-01-01T23:59:59.000Z

343

Partial Shading in Monolithic Thin Film PV Modules: Analysis...  

Broader source: Energy.gov (indexed) [DOE]

A. Alam, "Identification, Characterization and Implications of Shadow Degradation in Thin Film Solar Cells," in Reliability Physics Symposium (IRPS), 2011 IEEE International, 2011,...

344

Low-Cost Light Weigh Thin Film Solar Concentrators  

Broader source: Energy.gov (indexed) [DOE]

Light Weight Thin Film Solar Concentrators PI: Gani B. Ganapathi (JPLCaltech) Other Contributors: L'Garde: Art Palisoc, Gyula Greschik, Koorosh Gidanian JPL: Bill Nesmith,...

345

Thermochromic Properties of Nanocrystal-based Thin Films | The...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nanocrystal-based Thin Films Functional coatings that can selectively reflect or transmit near-infrared solar radiation while maintiaining high transmittance for visible light can...

346

In Situ Hydrogenation of Amorphous Silicon Prepared by Thermal Decomposition of Disilane  

Science Journals Connector (OSTI)

Thin hydrogenated amorphous silicon (a-Si:H) layers with thicknesses of 90-600 ? grown by thermal decomposition of disilane were treated with rf hydrogen plasma just after deposition at the same temperature (430-440?C). During this process (referred to as in situ hydrogenation), atomic hydrogen passivates defects, and the effective thickness of this passivated layer is estimated to be 220 ?. Atomic hydrogen also induces structural relaxation of the Si network even in a-Si:H deposited at high temperature (>400?C) while the change of bonded hydrogen content is rather small in in situ hydrogenation.

Mitsuyuki Yamanaka; Yutaka Hayashi; Isao Sakata

1993-01-01T23:59:59.000Z

347

Influence of deposition conditions on the 1/f noise in hydrogenated amorphous silicon  

SciTech Connect (OSTI)

The electronic properties of a series of n-type doped hydrogenated amorphous silicon (a-Si:H) films grown with deposition rates ranging from 2 {angstrom}/s to 33 {angstrom}/s have been studied. Infrared absorption spectroscopy shows an increase in Si-H{sub 2} content with deposition rate, concurrent with a decreasing conductivity, increasing thermal equilibration relaxation time, and increasing disorder at the mobility edge as measured by the difference in thermopower and dark conductivity activation energies. The current 1/f noise properties become highly nonstationary, with increased variability and inapplicability of statistical analysis as the deposition rate increases.

West, P.W.; Quicker, D.; Dyalsingh, H.M.; Kakalios, J.

1997-07-01T23:59:59.000Z

348

Method for sputtering a PIN microcrystalline/amorphous silicon semiconductor device with the P and N-layers sputtered from boron and phosphorous heavily doped targets  

DOE Patents [OSTI]

A silicon PIN microcrystalline/amorphous silicon semiconductor device is constructed by the sputtering of N, and P layers of silicon from silicon doped targets and the I layer from an undoped target, and at least one semi-transparent ohmic electrode.

Moustakas, Theodore D. (Annandale, NJ); Maruska, H. Paul (Annandale, NJ)

1985-04-02T23:59:59.000Z

349

Polycrystalline?thin?film thermophotovoltaic cells  

Science Journals Connector (OSTI)

Thermophotovoltaic (TPV) cells convert thermal energy to electricity. Modularity portability silent operation absence of moving parts reduced air pollution rapid start?up high power densities potentially high conversion efficiencies choice of a wide range of heat sources employing fossil fuels biomass and even solar radiation are key advantages of TPV cells in comparison with fuel cells thermionic and thermoelectric convertors and heat engines. The potential applications of TPV systems include: remote electricity supplies transportation co?generation electric?grid independent appliances and space aerospace and military power applications. The range of bandgaps for achieving high conversion efficiencies using low temperature (1000–2000 K) black?body or selective radiators is in the 0.5–0.75 eV range. Present high efficiency convertors are based on single crystalline materials such as In1?x Ga x As GaSb and Ga1?x In x Sb. Several polycrystalline thin films such as Hg1?x Cd x Te Sn1?x Cd2x Te2 and Pb1?x Cd x Te etc. have great potential for economic large?scale applications. A small fraction of the high concentration of charge carriers generated at high fluences effectively saturates the large density of defects in polycrystalline thin films. Photovoltaic conversion efficiencies of polycrystalline thin films and PV solar cells are comparable to single crystalline Si solar cells e.g. 17.1% for CuIn1?x Ga x Se2 and 15.8% for CdTe. The best recombination?state density N t is in the range of 10?15–10?16 cm?3 acceptable for TPV applications. Higher efficiencies may be achieved because of the higher fluences possibility of bandgap tailoring and use of selective emitters such as rare earth oxides (erbia holmia yttria) and rare earth?yttrium aluminium garnets. As compared to higher bandgap semiconductors such as CdTe it is easier to dope the lower bandgap semiconductors. TPV cell development can benefit from the more mature PV solar cell and opto?electronic (infrared detectors lasers and optical communications) technologies. Low bandgaps and larger fluences employed in TPV cells result in very high current densities which make it difficult to collect the current effectively. Techniques for laser and mechanical scribing integral interconnection and multi?junction tandem structures which have been fairly well developed for thin?film PV solar cells could be further refined for enhancing the voltages from TPV modules. Thin?film TPV cells may be deposited on metals or back?surface reflectors. Spectral control elements such as indium?tin oxide or tin oxide may be deposited directly on the TPV convertor. It would be possible to reduce the cost of TPV technologies based on single?crystal materials being developed at present to the range of US$ 2–5 per watt so as to be competitive in small to medium size commercial applications. However a further cost reduction to the range of US ¢ 35–$ 1 per watt to reach the more competitive large?scale residential consumer and hybrid?electric car markets would be possible only with the polycrystalline?thin film TPV cells.

Neelkanth G. Dhere

1996-01-01T23:59:59.000Z

350

Fully Solution-Processed Copper Chalcopyrite Thin Film Solar Cells: Materials Chemistry, Processing, and Device Physics  

E-Print Network [OSTI]

nanowire networks as window layers in thin film solar cells.window layer for fully solution-deposited thin filmITO) thin films by silver nanowire composite window layers

Chung, Choong-Heui

2012-01-01T23:59:59.000Z

351

Improved Stability Of Amorphous Zinc Tin Oxide Thin Film Transistors...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Instruments: Ultra-high Vacuum, Low-temperature Scanning Probe Microscope Instrument, or UHV LT SPM Tags: oxides ultra-high vacuum UHV VT SPM atomic-resolution imaging structural...

352

Solar-to-Hydrogen Photovoltaic/Photoelectrochemical Devices Using Amorphous Silicon Carbide as the Photoelectrode  

SciTech Connect (OSTI)

We report the use of hydrogenated amorphous silicon carbide (a-SiC:H) prepared by plasma enhanced chemical vapor deposition (PECVD) as the photoelectrode in an integrated 'hybrid' photoelectrochemical (PEC) cell to produce hydrogen directly from water using sunlight. Results on the durability of hydrogenated amorphous silicon carbide (a-SiC:H) photoelectrodes in an electrolyte are presented. In a pH2 electrolyte, the a-SiC:H photoelectrode exhibits excellent stability for 100 hour test so far performed. A photocurrent onset shift (anodically) after a 24- or 100-hour durability test in electrolyte is observed, likely due to changes in the surface chemical structure of the a-SiC:H photoelectrode. It is also observed that a thin SiOx layer native to the air exposed surface of the a-SiC:H affects the photocurrent and the its onset shift. Finally, approaches for eliminating the external bias voltage and enhancing the solar-to-hydrogen efficiency in a PV/PEC hybrid structure to achieve {>=} 10% are presented.

Hu, J.; Zhu, F.; Matulionis, I.; Kunrath, A.; Deutsch, T.; Kuritzky, L.; Miller, E.; Madan, A.

2008-01-01T23:59:59.000Z

353

Comparative Study of Low-temperature PECVD of Amorphous Silicon using Mono-, Di-, Trisilane and Cyclohexasilane  

SciTech Connect (OSTI)

The hydrogenated amorphous silicon a-Si:H films were grown by plasma-enhanced chemical vapor deposition (PECVD) using liquid cyclohexasilane Si{sub 6}H{sub 12} (CHS). The growth rate of a-Si:H was studied as a function of substrate temperatures in the range of 30 C < T < 450 C using deposition conditions that were optimized for monosilane SiH{sub 4}. The same parameters were used for a-Si:H films grown using disilane (Si{sub 2}H{sub 6}) and trisilane (Si{sub 3}H{sub 8}) precursors. It was found that the a-Si:H film growth rate for CHS is lower with respect to those for mono-, di- and trisilane in an Ar plasma. Addition of {approx}10% of H{sub 2} dramatically increases the deposition rate for CHS-based films to {_}nm/min - a 700% increase. The as-deposited films were characterized by FTIR and Raman spectroscopy to probe the hydrogen content and local bonding environment. It was found that the films grown using Ar/H{sub 2} mixtures as carrier gas have a reduced hydrogen content relative to polysilane fragments indicating higher quality amorphous silicon.

Konstantin Pokhodnya; Joseph Sandstrom; Xuliang Dai; Philip Boudjouk; Douglas L. Schulz

2009-06-08T23:59:59.000Z

354

Optical characteristics of pulsed laser deposited Ge-Sb-Te thin films studied by spectroscopic ellipsometry  

SciTech Connect (OSTI)

Pulsed laser deposition technique was used for the fabrication of (GeTe){sub 1-x}(Sb{sub 2}Te{sub 3}){sub x} (x = 0, 0.33, 0.50, 0.66, and 1) amorphous thin films. Scanning electron microscopy with energy-dispersive x-ray analysis, x-ray diffraction, optical reflectivity, and sheet resistance temperature dependences as well as variable angle spectroscopic ellipsometry measurements were used to characterize as-deposited (amorphous) and annealed (rocksaltlike) layers. In order to extract optical functions of the films, the Cody-Lorentz model was applied for the analysis of ellipsometric data. Fitted sets of Cody-Lorentz model parameters are discussed in relation with chemical composition and the structure of the layers. The GeTe component content was found to be responsible for the huge optical functions and thickness changes upon amorphous-to-fcc phase transition.

Nemec, P. [Department of Graphic Arts and Photophysics, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Prikryl, J.; Frumar, M. [Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 53210 Pardubice (Czech Republic); Nazabal, V. [Equipe Verres et Ceramiques, UMR-CNRS 6226, Sciences Chimiques de Rennes (SCR), Universite de Rennes 1, 35042 Rennes Cedex (France)

2011-04-01T23:59:59.000Z

355

Apparatus for laser assisted thin film deposition  

DOE Patents [OSTI]

A pulsed laser deposition apparatus uses fiber optics to deliver visible output beams. One or more optical fibers are coupled to one or more laser sources, and delivers visible output beams to a single chamber, to multiple targets in the chamber or to multiple chambers. The laser can run uninterrupted if one of the deposition chambers ceases to operate because other chambers can continue their laser deposition processes. The laser source can be positioned at a remote location relative to the deposition chamber. The use of fiber optics permits multi-plexing. A pulsed visible laser beam is directed at a generally non-perpendicular angle upon the target in the chamber, generating a plume of ions and energetic neutral species. A portion of the plume is deposited on a substrate as a thin film. A pulsed visible output beam with a high pulse repetition frequency is used. The high pulse repetition frequency is greater than 500 Hz, and more preferably, greater than about 1000 Hz. Diamond-like-carbon (DLC) is one of the thin films produced using the apparatus. 9 figs.

Warner, B.E.; McLean, W. II

1996-02-13T23:59:59.000Z

356

Calorimetry of dehydrogenation and dangling-bond recombination in several hydrogenated amorphous silicon materials  

Science Journals Connector (OSTI)

Differential scanning calorimetry (DSC) was used to study the dehydrogenation processes that take place in three hydrogenated amorphous silicon materials: nanoparticles, polymorphous silicon, and conventional device-quality amorphous silicon. Comparison of DSC thermograms with evolved gas analysis (EGA) has led to the identification of four dehydrogenation processes arising from polymeric chains (A), SiH groups at the surfaces of internal voids (A?), SiH groups at interfaces (B), and in the bulk (C). All of them are slightly exothermic with enthalpies below 50meV?(H atoms), indicating that, after dissociation of any SiH group, most dangling bonds recombine. The kinetics of the three low-temperature processes [with DSC peak temperatures at around 320 (A), 360 (A?), and 430°C (B)] exhibit a kinetic-compensation effect characterized by a linear relationship between the activation entropy and enthalpy, which constitutes their signature. Their Si?H bond-dissociation energies have been determined to be E(Si?H)0=3.14 (A), 3.19 (A?), and 3.28eV (B). In these cases it was possible to extract the formation energy E(DB) of the dangling bonds that recombine after Si?H bond breaking [0.97 (A), 1.05 (A?), and 1.12 (B)]. It is concluded that E(DB) increases with the degree of confinement and that E(DB)>1.10eV for the isolated dangling bond in the bulk. After Si?H dissociation and for the low-temperature processes, hydrogen is transported in molecular form and a low relaxation of the silicon network is promoted. This is in contrast to the high-temperature process for which the diffusion of H in atomic form induces a substantial lattice relaxation that, for the conventional amorphous sample, releases energy of around 600meV per H atom. It is argued that the density of sites in the Si network for H trapping diminishes during atomic diffusion.

P. Roura, J. Farjas, Chandana Rath, J. Serra-Miralles, E. Bertran, and P. Roca i Cabarrocas

2006-02-13T23:59:59.000Z

357

Experimental characterisations of thin film transmission line losses  

E-Print Network [OSTI]

Experimental characterisations of thin film transmission line losses D. Kim, H. Kim and Y. Eo New frequency-variant losses of planar thin film transmission lines are experimentally investigated in a broad frequency range. The fre- quency-variant transmission line parameters are accurately determined

358

Avalanches through windows: Multiscale visualization in magnetic thin films  

E-Print Network [OSTI]

Avalanches through windows: Multiscale visualization in magnetic thin films Alessandro Magni, Cornell University, Ithaca, NY 14853-2501 Abstract--The dynamics of domain walls motion in thin films dynamics, but are strongly dependent on the size of the windows chosen. Here we investigate how to properly

Sethna, James P.

359

Fracture patterns in thin films and multilayers Alex A. Volinsky  

E-Print Network [OSTI]

Fracture patterns in thin films and multilayers Alex A. Volinsky University of South Florida, excessive residual and externally applied stresses cause film fracture. In the case of tensile stress is the key for causing thin film fracture, either in tension, or compression, it is the influence

Volinsky, Alex A.

360

Advanced Thin Film Thermoelectric Systems forEfficient Air-Conditioner...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Thin Film Thermoelectric Systems forEfficient Air-Conditioners Advanced Thin Film Thermoelectric Systems forEfficient Air-Conditioners Presents recent advances in thermoelectric...

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Theory and simulation of amorphous organic electronic devices  

E-Print Network [OSTI]

The electronic properties of amorphous organic thin films are of great interest due to their application in devices such as light emitting devices, solar cells, photodetectors, and lasers. Compared to conventional inorganic ...

Madigan, Conor (Conor Francis), 1978-

2006-01-01T23:59:59.000Z

362

Electrochromic properties of iron oxide thin films prepared by chemical vapor deposition  

SciTech Connect (OSTI)

Iron oxide thin films were prepared by chemical vapor deposition. The source material was iron (III) acetylacetonate. The Fe{sub 2}O{sub 3} films were produced at a substrate temperature above 200 C. The films deposited at a substrate temperature above 300 C were polycrystalline {beta}-Fe{sub 2}O{sub 3}. Reduction and oxidation of the amorphous films in a 0.3 M LiClO{sub 4} propylene carbonate solution caused desirable changes in optical absorption. Coulometry indicated that the coloration efficiency was 6.0 to 6.5 cm{sup 2}/C.

Maruyama, Toshiro; Kanagawa, Tetsuya [Kyoto Univ. (Japan). Dept. of Chemical Engineering

1996-05-01T23:59:59.000Z

363

Exciton harvesting, charge transfer, and charge-carrier transport in amorphous-silicon nanopillar/polymer hybrid solar cells  

E-Print Network [OSTI]

report on the device physics of nanostructured amorphous-silicon a-Si:H /polymer hybrid solar cells and nanostructured a-Si:H/polymer systems. We find that strong energy transfer occurs in the a-Si:H/MEH-PPV system. However, inefficient hole transfer from the a-Si:H to the polymers renders negligible photocurrent

McGehee, Michael

364

Glow discharge plasma deposition of thin films  

DOE Patents [OSTI]

A glow discharge plasma reactor for deposition of thin films from a reactive RF glow discharge is provided with a screen positioned between the walls of the chamber and the cathode to confine the glow discharge region to within the region defined by the screen and the cathode. A substrate for receiving deposition material from a reactive gas is positioned outside the screened region. The screen is electrically connected to the system ground to thereby serve as the anode of the system. The energy of the reactive gas species is reduced as they diffuse through the screen to the substrate. Reactive gas is conducted directly into the glow discharge region through a centrally positioned distribution head to reduce contamination effects otherwise caused by secondary reaction products and impurities deposited on the reactor walls.

Weakliem, Herbert A. (Pennington, NJ); Vossen, Jr., John L. (Bridgewater, NJ)

1984-05-29T23:59:59.000Z

365

Thin Film Femtosecond Laser Damage Competition  

SciTech Connect (OSTI)

In order to determine the current status of thin film laser resistance within the private, academic, and government sectors, a damage competition was started at the 2008 Boulder Damage Symposium. This damage competition allows a direct comparison of the current state of the art of high laser resistance coatings since they are tested using the same damage test setup and the same protocol. In 2009 a high reflector coating was selected at a wavelength of 786 nm at normal incidence at a pulse length of 180 femtoseconds. A double blind test assured sample and submitter anonymity so only a summary of the results are presented here. In addition to the laser resistance results, details of deposition processes, coating materials and layer count, and spectral results will also be shared.

Stolz, C J; Ristau, D; Turowski, M; Blaschke, H

2009-11-14T23:59:59.000Z

366

High deposition rate preparation of amorphous silicon solar cells by rf glow discharge decomposition of disilane  

SciTech Connect (OSTI)

The optical and electrical properties of hydrogenated amorphous silicon films produced by rf glow discharge decomposition of disilane diluted in helium (Si/sub 2/H/sub 6//He = 1/9) have been studied while systematically varying the film deposition rate. The properties and composition of the films were monitored by measuring the optical band gap, IR vibrational spectrum, dark conductivity, and the photoconductivity as a function of the deposition rate. The photoluminescence of the high deposition rate films gave a peak at 1.33 eV. These films, whose properties are rather similar to those of the conventional a-Si:H films prepared from monosilane, have been used to fabricate nip-type a-Si:H solar cells. At a deposition rate of 11 A/sec, a conversion efficiency of 6.86% was obtained. This high efficiency shows that disilane is applicable for mass production fabrication of a-Si:H solar cells.

Kenne, J.; Ohashi, Y.; Matsushita, T.; Konagai, M.; Takahashi, K.

1984-01-15T23:59:59.000Z

367

Plasma-assisted CVD of fluorinated, hydrogenated amorphous silicon. Final report  

SciTech Connect (OSTI)

During the past year, three novel large-area (100 cm/sup 2/) a-Si:H solar cells were developed with the following configurations: inverted NIP/SS cells with an improved red response; inverted a-Si:H/a-B:H heterojunction cells with high V/sub oc/; and NIP/metal cells with a CVD P-layer grown pyrolytically from silane and diborane. Initial experiments were performed using disilane as the deposition gas for the intrinsic layer in both NIP/SS and PIN/SS structures. Coatings of In/sub 2/O/sub 3/, using a technique developed by Dr. Ovadyahu, were applied to NIP/SS cells in order to evaluate its potential as a conductive coating in practical amorphous silicon solar cells.

Coleman, J.H.; Hammes, J.P.; Wiesmann, H.J.

1981-01-01T23:59:59.000Z

368

Exciton splitting and carrier transport across the amorphous-silicon/polymer solar cell interface  

Science Journals Connector (OSTI)

The authors study exciton splitting at the interface of bilayer hybridsolar cells to better understand the physics controlling organic-inorganicdevice performance. Hydrogenated amorphous silicon ( a - Si : H ) ? poly ( 3 - hexylthiophene ) (P3HT) and a - Si : H ? poly ( 2 - methoxy - 5 - ( 2 ? - ethyl - hexyloxy ) - 1 4 - phenylenevinylene ) (MEH-PPV) solar cells show photoresponse dominated by exciton production in the polymer. The a - Si : H ? P 3 HT devices are nearly as efficient as titania/P3HT cells. However the a - Si : H ? MEH - PPV system has much lower photocurrent than a - Si : H ? P 3 HT likely due to inefficient hole transfer back to the MEH-PPV after energy transfer from MEH-PPV to a - Si : H .

Vignesh Gowrishankar; Shawn R. Scully; Michael D. McGehee; Qi Wang; Howard M. Branz

2006-01-01T23:59:59.000Z

369

Broadband, stable and highly coherent supercontinuum generation at telecommunication wavelengths in an hydrogenated amorphous silicon waveguide  

E-Print Network [OSTI]

Hydrogenated amorphous silicon (a:Si-H) has recently been recognized as a highly nonlinear CMOS compatible photonic platform. We experimentally demonstrate the generation of a supercontinuum (SC) spanning over 500 nm in a-Si:H photonic wire waveguide at telecommunication wavelengths using femtosecond input pulse with energy lower than 5 pJ. Numerical modeling of pulse propagation in the waveguide, based on the experimentally characterized dispersion profile, shows that the supercontinuum is the result of soliton fission and dispersive wave generation. It is demonstrated that the SC is highly coherent and that the waveguides do not suffer from material degradation under femtosecond pulse illumination. Finally, a direct comparison of SC generation in c-Si and a-Si:H waveguides confirms the higher performances of a-Si:H over c-Si for broadband low power SC generation at telecommunication wavelengths.

Leo, F; Kuyken, B; Roelkens, G; Gorza, S -P

2014-01-01T23:59:59.000Z

370

FTIR (Fourier transform infrared) spectrophotometry for thin film monitors: Computer and equipment integration for enhanced capabilities  

SciTech Connect (OSTI)

Fourier transform infrared spectrophotometry (FTIR) is a valuable technique for monitoring thin films used in semiconductor device manufacture. Determinations of the constituent contents in borophosphosilicate (BPSG), phosphosilicate (PSG), silicon oxynitride (SiON:H,OH), and spin-on-glass (SOG) thin films are a few applications. Due to the nature of the technique, FTIR instrumentation is one of the most extensively computer-dependent pieces of equipment that is likely to be found in a microelectronics plant. In the role of fab monitor or reactor characterization tool, FTIR instruments can rapidly generate large amounts of data. By linking a local FTIR data station to a remote minicomputer its capabilities are greatly improved. We discuss three caused of enhancement. First, the FTIR in the fab area communicates and interacts in real time with the minicomputer: transferring data segments to it, instructing it to perform sophisticated processing, and returning the result to the operator in the fab. Characterizations of PSG thin films by this approach are discussed. Second, the spectra of large numbers of samples are processed locally. The large database is then transmitted to the minicomputer for study by statistical/graphics software. Results of CVD-reactor spatial profiling experiments for plasma SiON are presented. Third, processing of calibration spectra is performed on the minicomputer to optimize the accuracy and precision of a Partial Least Squares'' analysis mode. This model is then transferred to the data station in the fab. The analysis of BPSG thin films is discussed in this regard. The prospects for fully automated at-line monitoring and for real-time, in-situ monitoring will be discussed. 10 refs., 4 figs.

Cox, J.N.; Sedayao, J.; Shergill, G.; Villasol, R. (Intel Corp., Santa Clara, CA (USA)); Haaland, D.M. (Sandia National Labs., Albuquerque, NM (USA))

1990-01-01T23:59:59.000Z

371

Bulge testing of single and dual layer thin films Dryver R. Huston*ab  

E-Print Network [OSTI]

to a thin film window. By comparing the pressure- displacement relation with a mechanical model, the elastic structures, such as the thin film windows that are used in Next Generation Lithography masks and certain MEMS it in a thin film window. Thin film windows are fabricated by removing the thick substrate out from underneath

Huston, Dryver R.

372

Focused ion beam specimen preparation for electron holography of electrically biased thin film solar cells  

E-Print Network [OSTI]

, biased TEM specimen, thin film solar cell, FIB Thin films of hydrogenated Si (Si:H) can be used as active for electron holography of a thin film solar cell using conventional lift-out specimen preparation and a homeFocused ion beam specimen preparation for electron holography of electrically biased thin film

Dunin-Borkowski, Rafal E.

373

DISSERTATION DEVICE PHYSICS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS  

E-Print Network [OSTI]

DISSERTATION DEVICE PHYSICS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS Submitted by Markus Gloeckler PHYSICS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS BE ACCEPTED AS FULFILLING IN PART REQUIREMENTS OF Cu(In,Ga)Se2 THIN-FILM SOLAR CELLS Thin-film solar cells have the potential to be an important

Sites, James R.

374

Composition–Structure–Function Diagrams of Ti–Ni–Au Thin Film Shape Memory Alloys  

Science Journals Connector (OSTI)

thin films; annealing; high temperature shape memory alloys; combinatorial materials science; phase transformation ...

Pio John S. Buenconsejo; Alfred Ludwig

2014-11-04T23:59:59.000Z

375

Crystallization characteristics and chemical bonding properties of nickel carbide thin film nanocomposites  

E-Print Network [OSTI]

The crystal structure and chemical bonding of magnetron-sputtering deposited nickel carbide Ni$_{1-x}$C$_{x}$ (0.05$\\leq$x$\\leq$0.62) thin films have been investigated by high-resolution X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and soft X-ray absorption spectroscopy. By using X-ray as well as electron diffraction, we found carbon-containing hcp-Ni (hcp-NiC$_{y}$ phase), instead of the expected rhombohedral-Ni$_{3}$C. At low carbon content (4.9 at\\%) the thin film consists of hcp-NiC$_{y}$ nanocrystallites mixed with a smaller amount of fcc-NiC$_{x}$. The average grain size is about 10-20 nm. With the increase of carbon content to 16.3 at\\%, the film contains single-phase hcp-NiC$_{y}$ nanocrystallites with expanded lattice parameters. With further increase of carbon content to 38 at\\%, and 62 at\\%, the films transform to X-ray amorphous materials with hcp-NiC$_{y}$ and fcc-NiC$_{x }$ nanodomain structures in an amorphous carbon-rich matrix. Ram...

Furlan, Andrej; Hultman, Lars; Jansson, Ulf; Magnuson, Martin

2014-01-01T23:59:59.000Z

376

Thin Ni silicide formation by low temperature-induced metal atom reaction with ion implanted amorphous silicon  

SciTech Connect (OSTI)

We have extended our recent work on buried silicide formation by Ni diffusion into a buried amorphous silicon layer to the case where silicide formation is at lower temperatures on silicon substrates which have been preamorphized. The reaction of metal atoms from a 12 nm Ni film evaporated on top of a 65 nm thick surface amorphous layer formed by 35 keV Si{sup +} ion implantation has been investigated at temperature {le}400C. Rutherford Backscattering Spectrometry (RBS) with channeling, cross-sectional transmission electron microscopy (XTEM), x-ray diffraction and four-point-probe measurements were used to determine structure, interfacial morphology, composition and resistivity of the silicide films. It has been found that an increased rate of silicidation occurs for amorphous silicon with respect to crystalline areas permitting a selective control of the silicon area to be contacted during silicide growth. Vacuum furnace annealing at 360C for 8 hours followed by an additional step at 400C for one hour produces a continuos NiSi{sub 2} layer with a resistivity 44 {mu}{Omega} cm.

Erokhin, Yu.N.; Pramanick, S.; Hong, F.; Rozgonyi, G.A. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering; Patnaik, B.K. [North Carolina State Univ., Raleigh, NC (United States)

1992-12-31T23:59:59.000Z

377

Functionalized multilayer thin films for protection against acutely toxic agents  

E-Print Network [OSTI]

The recently developed practice of spraying polyelectrolyte solutions onto a substrate in order to construct thin films via the Layer-by-Layer (LbL) technique has been further investigated and extended. In this process a ...

Krogman, Kevin Christopher

2009-01-01T23:59:59.000Z

378

Laser scribing of CIGS based thin films solar cells  

Science Journals Connector (OSTI)

Laser scribing tests on CIGS based thin films solar cells have been performed. The obtained high quality incisions show that laser scribing is a valuable tool for producing low-cost...

Sozzi, Michele; Menossi, Daniele; Bosio, Alessio; Cucinotta, Annamaria; Romeo, Nicola; Selleri, Stefano

379

Polycrystalline Thin-Film Research: Cadmium Telluride (Fact Sheet)  

SciTech Connect (OSTI)

This National Center for Photovoltaics sheet describes the capabilities of its polycrystalline thin-film research in the area of cadmium telluride. The scope and core competencies and capabilities are discussed.

Not Available

2013-06-01T23:59:59.000Z

380

National High Magnetic Field Laboratory: Magnetic Thin Films  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

recorded work with magnetic thin films took place in the 1880s and was carried out by German physicist August Kundt. Well known for his research on sound and optics, Kundts...

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Picosecond laser ablation of nano-sized WTi thin film  

Science Journals Connector (OSTI)

Interaction of an Nd:YAG laser, operating at 532 nm wavelength and pulse duration of 40 ps, with tungsten-titanium (WTi) thin film (thickness, 190 nm)...2...were found to be sufficient for modification of the WTi

S. Petrovi?; B. Gakovi?; D. Peruško; T. Desai; D. Batani; M. ?ekada…

2009-08-01T23:59:59.000Z

382

Flexible, transparent thin film transistors raise hopes for flexible...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

screens and displays. Virtually all flat-screen TVs and smartphones are made up of thin film transistors today; they form the basis of both LEDs and LCDs (liquid crystal...

383

Role of Microstructural Phenomena in Magnetic Thin Films. Final Report  

SciTech Connect (OSTI)

Over the period of the program we systematically varied microstructural features of magnetic thin films in an attempt to better identify the role which each feature plays in determining selected extrinsic magnetic properties. This report summarizes the results.

Laughlin, D. E.; Lambeth, D. N.

2001-04-30T23:59:59.000Z

384

Self-Assembling Process for Fabricating Tailored Thin Films  

ScienceCinema (OSTI)

A simple, economical nanotechnology coating process that enables the development of nanoparticle thin films with architectures and properties unattainable by any other processing method. 2007 R&D 100 winner (SAND2007-1878P)

Sandia

2009-09-01T23:59:59.000Z

385

Self-Assembling Process for Fabricating Tailored Thin Films  

ScienceCinema (OSTI)

A simple, economical nanotechnology coating process that enables the development of nanoparticle thin films with architectures and properties unattainable by any other processing method. 2007 R&D 100 winner (SAND2007-1878P)

None

2010-01-08T23:59:59.000Z

386

Initiated chemical vapor deposition of functional polyacrylic thin films  

E-Print Network [OSTI]

Initiated chemical vapor deposition (iCVD) was explored as a novel method for synthesis of functional polyacrylic thin films. The process introduces a peroxide initiator, which can be decomposed at low temperatures (<200?C) ...

Mao, Yu, 1975-

2005-01-01T23:59:59.000Z

387

Direct printing of lead zirconate titanate thin films  

E-Print Network [OSTI]

Thus far, use of lead zirconate titanate (PZT) in MEMS has been limited due to the lack of process compatibility with existing MEMS manufacturing techniques. Direct printing of thin films eliminates the need for photolithographic ...

Bathurst, Stephen, 1980-

2008-01-01T23:59:59.000Z

388

Peeling Back the Layers of Thin Film Structure and Chemistry  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

July 10, 2014 Bookmark and Share The layer-by-layer analysis of the concentration of strontium within a 40-angstrom thick (La, Sr)CoO thin film applied to a SiTiO3 substrate....

389

Modeling of thin-film solar thermoelectric generators  

E-Print Network [OSTI]

Recent advances in solar thermoelectric generator (STEG) performance have raised their prospect as a potential technology to convert solar energy into electricity. This paper presents an analysis of thin-film STEGs. ...

Weinstein, Lee Adragon

390

Nanostructured thin films for solid oxide fuel cells  

E-Print Network [OSTI]

The goals of this work were to synthesize high performance perovskite based thin film solid oxide fuel cell (TF-SOFC) cathodes by pulsed laser deposition (PLD), to study the structural, electrical and electrochemical properties of these cathodes...

Yoon, Jongsik

2009-05-15T23:59:59.000Z

391

Monolithic integration of thin-film coolers with optoelectronic devices  

E-Print Network [OSTI]

Monolithic integration of thin-film coolers with optoelectronic devices Christopher La Barbara, California 93106-9560 Abstract. Active refrigeration of optoelectronic components through the use manuscript received June 30, 2000; accepted for publication June 30, 2000. 1 Introduction Optoelectronic

392

Enabling integration of vapor-deposited polymer thin films  

E-Print Network [OSTI]

Initiated Chemical Vapor Deposition (iCVD) is a versatile, one-step process for synthesizing conformal and functional polymer thin films on a variety of substrates. This thesis emphasizes the development of tools to further ...

Petruczok, Christy D. (Christy Danielle)

2014-01-01T23:59:59.000Z

393

Method for making surfactant-templated thin films  

DOE Patents [OSTI]

An evaporation-induced self-assembly method to prepare a porous, surfactant-templated, thin film by mixing a silica sol, a solvent, a surfactant, and an interstitial compound, evaporating a portion of the solvent to form a liquid, crystalline thin film mesophase material, and then removal of the surfactant template. Coating onto a substrate produces a thin film with the interstitial compound either covalently bonded to the internal surfaces of the ordered or disordered mesostructure framework or physically entrapped within the ordered or disordered mesostructured framework. Particles can be formed by aerosol processing or spray drying rather than coating onto a substrate. The selection of the interstitial compound provides a means for developing thin films for applications including membranes, sensors, low dielectric constant films, photonic materials and optical hosts.

Brinker, C. Jeffrey (Albuquerque, NM); Lu, Yunfeng (New Orleans, LA); Fan, Hong You (Albuquerque, NM)

2010-08-31T23:59:59.000Z

394

Method for making surfactant-templated thin films  

DOE Patents [OSTI]

An evaporation-induced self-assembly method to prepare a porous, surfactant-templated, thin film by mixing a silica sol, a solvent, a surfactant, and an interstitial compound, evaporating a portion of the solvent to form a liquid, crystalline thin film mesophase material, and then removal of the surfactant template. Coating onto a substrate produces a thin film with the interstitial compound either covalently bonded to the internal surfaces of the ordered or disordered mesostructure framework or physically entrapped within the ordered or disordered mesostructured framework. Particles can be formed by aerosol processing or spray drying rather than coating onto a substrate. The selection of the interstitial compound provides a means for developing thin films for applications including membranes, sensors, low dielectric constant films, photonic materials and optical hosts.

Brinker, C. Jeffrey (Albuquerque, NM); Lu, Yunfeng (San Jose, CA); Fan, Hongyou (Albuquerque, NM)

2002-01-01T23:59:59.000Z

395

Properties and sensor performance of zinc oxide thin films  

E-Print Network [OSTI]

Reactively sputtered ZnO thin film gas sensors were fabricated onto Si wafers. The atmosphere dependent electrical response of the ZnO micro arrays was examined. The effects of processing conditions on the properties and ...

Min, Yongki, 1965-

2003-01-01T23:59:59.000Z

396

Magnetic Skyrmion Phase in MnSi Thin Films.  

E-Print Network [OSTI]

??Detailed magnetometry and polarized neutron reflectometry studies were conducted on MnSi thin films grown epitaxially on Si(111) substrates. It is demonstrated that with an in-plane… (more)

Wilson, Murray

2013-01-01T23:59:59.000Z

397

Novel silane and disilane precursors to amorphous semiconductors. Annual report, 1 April 1985-31 March 1986  

SciTech Connect (OSTI)

This report describes the preparation and characterization of amorphous fluorohydrogenated silicon thin films. The novel approach lies in the use of fluorinated silanes as film precursors. This method has the advantages of well-defined initial ratios of hydrogen and fluorine and a greatly reduced hazards in the handling of the gas. Fluorine derivatives of both silane and disilane were synthesized. A conventional method, glow discharge (or plasma-enhanced chemical vapor deposition), was employed to prepare amorphous silicon on glass and Si wafers. The electrical characterization of the material prepared from difluorosilane (the main precursor during the contract period covered in this report) showed that the a-Si:H:F films obtained are of solar-grade semiconductor quality and can be doped to p- and n-type material with diborane and phosphine.

Pernisz, U.; Sharp, K.

1986-08-01T23:59:59.000Z

398

E-Print Network 3.0 - amorphous silicon research Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Silicon Silicon is the second most... distinct forms. The possibility of a phase transition between two liquid forms in silicon, ... Source: Goldberg, Bennett - Department of...

399

Temperature effect on low-k dielectric thin films studied by ERDA  

SciTech Connect (OSTI)

Low-k dielectric materials are becoming increasingly interesting as alternative to SiO2 with device geometries shrinking beyond the 65 nm technology node. At elevated temperatures hydrogen migration becomes an important degradation mechanism for conductivity breakdown in semiconductor devices. The possibility of hydrogen release during the fabrication process is, therefore, of great interest in the understanding of device reliability. In this study, various low-k dielectric films were subjected to thermal annealing at temperatures that are generally used for device fabrication. Elastic recoil detection analysis (ERDA) was used to investigate compositional changes and hydrogen redistribution in thin films of plasma-enhanced tetraethylortho-silicate (PETEOS), phosphorus doped silicon glass (PSG), silicon nitride (SiN) and silicon oxynitride (SiON). Except for an initial hydrogen release from the surface region in films of PETEOS and PSG, the results indicate that the elemental composition of the films was stable for at least 2 hours at 450?C.

Jensen, Jens; Possnert, Göran; Zhang, Yanwen

2008-09-23T23:59:59.000Z

400

Boron arsenide thin film solar cell development. Final report  

SciTech Connect (OSTI)

Pyrolytic decomposition of diborane and arsine has been used in attempts to grow polycrystalline BAs films. This method, however, produced only amorphous films for deposition temperatures below 920/sup 0/C and polycrystalline boron subarsenide (B/sub 12/As/sub 2/) flms for deposition temperatures above this value. The amorphous films have been determined to have a significant arsenic content but the actual stoichiometry was not obtained. The films were adherent on single crystal sapphire (0001), (111) silicon, (0001) SiC, and polycrystalline SiC but were found not to be adherent to substrates of fused quartz, tungsten, and molybdenum. It was also found that all films deposited above 650/sup 0/C were p-type while those deposited below 600/sup 0/C were usually n-type. Polycrystalline BAs and B/sub 12/As/sub 2/ was produced by reaction of the elements in a closed tube. The amorphous films showed an indirect or non-direct optical bandgap from 1.0 to 1.7 eV with the most probable values between 1.2 to 1.4 eV. The crystalline BAs powder shows a bandgap near 1.0 eV. Photoconductance time constants have been measured for films deposited on (0001) sapphire and (0001) SiC. Attempts at doping the amorphous films were generally unsuccessful. A polycrystalline powder sample was successfully doped with sulfur. Attempts were made to produce a Schottky barrier diode by evaporating Al dots onto an amorphous film on graphite without a post-evaporation anneal. An MIS structure was also attempted by baking an amorphous film in air at 280/sup 0/C before evaporation of aluminum. Although nonlinear characteristics were obtained, none of the devices showed any photovoltaic response. A p-type amorphous film was deposited on an n-type silicon substrate to form a p-n heterojunction. This device did exhibit a photovoltaic response but it is believed that the photogeneration was occurring primarily in the silicon substrate.

Boone, J.L.; Van Doren, T.P.

1980-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Josephson junction in a thin film  

SciTech Connect (OSTI)

The phase difference {phi}(y) for a vortex at a line Josephson junction in a thin film attenuates at large distances as a power law, unlike the case of a bulk junction where it approaches exponentially the constant values at infinities. The field of a Josephson vortex is a superposition of fields of standard Pearl vortices distributed along the junction with the line density {phi}'(y)/2{pi}. We study the integral equation for {phi}(y) and show that the phase is sensitive to the ratio l/{Lambda}, where l={lambda}{sub J}{sup 2}/{lambda}{sub L}, {Lambda}=2{lambda}{sub L}{sup 2}/d, {lambda}{sub L}, and {lambda}{sub J} are the London and Josephson penetration depths, and d is the film thickness. For l<<{Lambda}, the vortex ''core'' of the size l is nearly temperature independent, while the phase ''tail'' scales as l{Lambda}/y{sup 2}={lambda}{sub J}2{lambda}{sub L}/d/y{sup 2}; i.e., it diverges as T{yields}T{sub c}. For l>>{Lambda}, both the core and the tail have nearly the same characteristic length l{Lambda}.

Kogan, V. G.; Dobrovitski, V. V.; Clem, J. R.; Mawatari, Yasunori; Mints, R. G.

2001-04-01T23:59:59.000Z

402

Optical switching and photoluminescence in erbium-implanted vanadium dioxide thin films  

SciTech Connect (OSTI)

Vanadium dioxide (VO{sub 2}) is under intensive consideration for optical switching due to its reversible phase transition, which features a drastic and rapid shift in infrared reflectivity. Classified as an insulator–to–metal transition, the phase transition in VO{sub 2} can be induced thermally, electrically, and optically. When induced optically, the transition can occur on sub-picosecond time scales. It is interesting to dope VO{sub 2} with erbium ions (Er{sup 3+}) and observe their combined properties. The first excited-state luminescence of Er{sup 3+} lies within the wavelength window of minimal transmission-loss in silicon and has been widely utilized for signal amplification and generation in silicon photonics. The incorporation of Er{sup 3+} into VO{sub 2} could therefore result in a novel photonic material capable of simultaneous optical switching and amplification. In this work, we investigate the optical switching and photoluminescence in Er-implanted VO{sub 2} thin films. Thermally driven optical switching is demonstrated in the Er-implanted VO{sub 2} by infrared reflectometry. Photoluminescence is observed in the thin films annealed at ?800?°C or above. In addition, Raman spectroscopy and a statistical analysis of switching hysteresis are carried out to assess the effects of the ion implantation on the VO{sub 2} thin films. We conclude that Er-implanted VO{sub 2} can function as an optical switch and amplifier, but with reduced switching quality compared to pure VO{sub 2}.

Lim, Herianto, E-mail: mail@heriantolim.com; Stavrias, Nikolas; Johnson, Brett C.; McCallum, Jeffrey C. [School of Physics, University of Melbourne, Parkville, Victoria 3010 (Australia); Marvel, Robert E.; Haglund, Richard F. [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37240 (United States)

2014-03-07T23:59:59.000Z

403

Method for sputtering a PIN amorphous silicon semi-conductor device having partially crystallized P and N-layers  

DOE Patents [OSTI]

A high efficiency amorphous silicon PIN semiconductor device having partially crystallized (microcrystalline) P and N layers is constructed by the sequential sputtering of N, I and P layers and at least one semi-transparent ohmic electrode. The method of construction produces a PIN device, exhibiting enhanced electrical and optical properties, improved physical integrity, and facilitates the preparation in a singular vacuum system and vacuum pump down procedure.

Moustakas, Theodore D. (Annandale, NJ); Maruska, H. Paul (Annandale, NJ)

1985-07-09T23:59:59.000Z

404

Gas-phase free radical reactions in the glow-discharge deposition of hydrogenated amorphous silicon from silane and disilane  

SciTech Connect (OSTI)

An analysis of a measurement by Matsuda and co-workers of the lifetimes of the free radicals involved in the glow-discharge deposition of amorphous hydrogenated silicon from silane and disilane at 20-mTorr pressure is consistent with the hypothesis that SiH or SiH/sub 2/, but not SiH/sub 3/, is the dominant radical in the deposition from silane at that pressure.

Kampas, F.J.

1985-03-15T23:59:59.000Z

405

Increasing Stabilized Performance Of Amorphous Silicon Based Devices Produced By Highly Hydrogen Diluted Lower Temperature Plasma Deposition.  

DOE Patents [OSTI]

High quality, stable photovoltaic and electronic amorphous silicon devices which effectively resist light-induced degradation and current-induced degradation, are produced by a special plasma deposition process. Powerful, efficient single and multi-junction solar cells with high open circuit voltages and fill factors and with wider bandgaps, can be economically fabricated by the special plasma deposition process. The preferred process includes relatively low temperature, high pressure, glow discharge of silane in the presence of a high concentration of hydrogen gas.

Li, Yaun-Min (Langhorne, PA); Bennett, Murray S. (Langhorne, PA); Yang, Liyou (Plainsboro, NJ)

1999-08-24T23:59:59.000Z

406

Increased Stabilized Performance Of Amorphous Silicon Based Devices Produced By Highly Hydrogen Diluted Lower Temperature Plasma Deposition.  

DOE Patents [OSTI]

High quality, stable photovoltaic and electronic amorphous silicon devices which effectively resist light-induced degradation and current-induced degradation, are produced by a special plasma deposition process. Powerful, efficient single and multi-junction solar cells with high open circuit voltages and fill factors and with wider bandgaps, can be economically fabricated by the special plasma deposition process. The preferred process includes relatively low temperature, high pressure, glow discharge of silane in the presence of a high concentration of hydrogen gas.

Li, Yaun-Min (Langhorne, PA); Bennett, Murray S. (Langhorne, PA); Yang, Liyou (Plainsboro, NJ)

1997-07-08T23:59:59.000Z

407

Microelectronically fabricated LiCoO2/SiO2/polycrystalline-silicon power cells planarized by chemical mechanical polishing  

E-Print Network [OSTI]

. Integrating a power unit onto a silicon chip requires the implementation of a thin-film solid-state battery as a solid-state electrolyte in our integrated thin-film battery. This SiO2 electrolyte layer is thermally in the fabrication of the integrated solid-state thin-film lithium-ion battery. Polishing the polysilicon layer

408

An improved thin film approximation to accurately determine the optical conductivity of graphene from infrared transmittance  

SciTech Connect (OSTI)

This work presents an improved thin film approximation to extract the optical conductivity from infrared transmittance in a simple yet accurate way. This approximation takes into account the incoherent reflections from the backside of the substrate. These reflections are shown to have a significant effect on the extracted optical conductivity and hence on derived parameters as carrier mobility and density. By excluding the backside reflections, the error for these parameters for typical chemical vapor deposited (CVD) graphene on a silicon substrate can be as high as 17% and 45% for the carrier mobility and density, respectively. For the mid- and near-infrared, the approximation can be simplified such that the real part of the optical conductivity is extracted without the need for a parameterization of the optical conductivity. This direct extraction is shown for Fourier transform infrared (FTIR) transmittance measurements of CVD graphene on silicon in the photon energy range of 370–7000?cm{sup ?1}. From the real part of the optical conductivity, the carrier density, mobility, and number of graphene layers are determined but also residue, originating from the graphene transfer, is detected. FTIR transmittance analyzed with the improved thin film approximation is shown to be a non-invasive, easy, and accurate measurement and analysis method for assessing the quality of graphene and can be used for other 2-D materials.

Weber, J. W.; Bol, A. A. [Department of Applied Physics, Eindhoven University of Technology, Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Sanden, M. C. M. van de [Department of Applied Physics, Eindhoven University of Technology, Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Dutch Institute for Fundamental Energy Research (DIFFER), Nieuwegein (Netherlands)

2014-07-07T23:59:59.000Z

409

Nitrogen doped zinc oxide thin film  

SciTech Connect (OSTI)

To summarize, polycrystalline ZnO thin films were grown by reactive sputtering. Nitrogen was introduced into the films by reactive sputtering in an NO{sub 2} plasma or by N{sup +} implantation. All ZnO films grown show n-type conductivity. In unintentionally doped ZnO films, the n-type conductivities are attributed to Zn{sub i}, a native shallow donor. In NO{sub 2}-grown ZnO films, the n-type conductivity is attributed to (N{sub 2}){sub O}, a shallow double donor. In NO{sub 2}-grown ZnO films, 0.3 atomic % nitrogen was found to exist in the form of N{sub 2}O and N{sub 2}. Upon annealing, N{sub 2}O decomposes into N{sub 2} and O{sub 2}. In furnace-annealed samples N{sub 2} redistributes diffusively and forms gaseous N{sub 2} bubbles in the films. Unintentionally doped ZnO films were grown at different oxygen partial pressures. Zni was found to form even at oxygen-rich condition and led to n-type conductivity. N{sup +} implantation into unintentionally doped ZnO film deteriorates the crystallinity and optical properties and leads to higher electron concentration. The free electrons in the implanted films are attributed to the defects introduced by implantation and formation of (N{sub 2}){sub O} and Zni. Although today there is still no reliable means to produce good quality, stable p-type ZnO material, ZnO remains an attractive material with potential for high performance short wavelength optoelectronic devices. One may argue that gallium nitride was in a similar situation a decade ago. Although we did not obtain any p-type conductivity, we hope our research will provide a valuable reference to the literature.

Li, Sonny X.

2003-12-15T23:59:59.000Z

410

Photochemical vapor deposition of undoped and n-type amorphous silicon films produced from disilane  

SciTech Connect (OSTI)

Hydrogenated amorphous silicon films have been deposited by mercury photosensitized decomposition (photochemical vapor deposition: photo-CVD) of disilane at a substrate temperature below 300 /sup 0/C. The structural and optical properties of undoped films are very similar to those of films deposited by rf glow discharge decomposition. The electronic property measurement shows that the conductivity strongly depends on the substrate temperature during deposition. The photoconductivity reaches 5.7 x 10/sup -3/ (..cap omega.. cm)/sup -1/ (AM1,100 mW/cm/sup 2/) at a substrate temperature of 200 /sup 0/C. The dark conductivity is 10/sup -6/--10/sup -8/ (..cap omega.. cm)/sup -1/ and the Fermi level is located near the middle of the gap. n-type doping has been also achieved by adding phosphine as an impurity to disilane. Furthermore, a p-i-n a-Si solar cell was fabricated using photo-CVD undoped and P-doped films. The initial cell showed a conversion efficiency of 4.39% under AM1 insolation.

Inoue, T.; Konagai, M.; Takahashi, K.

1983-10-15T23:59:59.000Z

411

Electron spin resonance of ultrahigh vacuum evaporated amorphous silicon: In situ and ex situ studies  

Science Journals Connector (OSTI)

An in situ study of the electron spin resonance (ESR) of ultrahigh vacuum evaporated amorphous silicon is performed to define the characteristics of the signal as a function of preparation conditions. The influence of deposition rate, temperature of substrates, temperature of annealing, angle of incidence of the vapor beam, contamination by air exposure, and the presence of hydrogen during growth have been investigated. Porosity effects depending on thermal history and angle of incidence, which allow contamination, are observed by ESR. It is found that the spin density is mainly determined by the thermal history and varies only within a factor of about 3 when contamination effects are not involved. This is contrary to other results which we believe were obtained from contaminated specimens. Related variations of linewidth and saturation behavior are observed. Ex situ measurements of linewidth, saturation behavior, and ESR susceptibility are done as a function of temperature. The results of these measurements are discussed in terms of two extreme possibilities for spins: individual spins randomly distributed and clusters of spins. The question of a possible association of spins with voids is also discussed. The results are compatible with a model of individual spins randomly distributed. An approach to the relation between spins and conductivity is presented.

P. A. Thomas; M. H. Brodsky; D. Kaplan; D. Lepine

1978-10-01T23:59:59.000Z

412

Stability of hydrogenated amorphous silicon deposited at high temperatures with a remote hydrogen plasma  

Science Journals Connector (OSTI)

It is demonstrated that the stability of hydrogenated amorphous silicon (a?Si:H) is improved by deposition under the combined conditions of high substrate temperature (e.g. T D =400?°C) and high hydrogen dilution as are readily achieved in a remote hydrogen plasma reactor. In comparison with optimized films from conventional rfglow dischargedeposition (e.g. silane 230?°C 2 W) undoped high T D films possess a lower midgap defect density the dark dc conductivity in n?type (phosphorus?doped) films displays higher equilibration temperatures and longer relaxation times at a given temperature with an activation energy of 1.0 eV and undoped high T D films have a lower saturated density of light?induced defects. It is proposed that the ability to achieve the improved stability is a consequence of two effects: (1) the use of hydrogen dilution during deposition to maintain the hydrogen concentration in the film near 10 at.?% even at 400?°C and (2) the possibility that at high T D ’s the hydrogen is more stably incorporated in the random network and/or that the density of weak Si—Si bonds is smaller.

N. M. Johnson; C. E. Nebel; P. V. Santos; W. B. Jackson; R. A. Street; K. S. Stevens; J. Walker

1991-01-01T23:59:59.000Z

413

Tight-binding study of the electronic structure of amorphous silicon  

Science Journals Connector (OSTI)

We have performed tight-binding calculations on a model of an amorphous silicon sample generated previously by a molecular-dynamics simulation employing the Stillinger-Weber potential. The sample consists of 588 atoms and contains a high density of floating-bond defects. Two tight-binding calculations are presented, one using the widely accepted Chadi parameters, which include only nearest-neighbor interactions, and the other using the parameters recently proposed by Allen, Broughton, and McMahan (ABM) [Phys. Rev. B 34, 859 (1986)] for a nonorthogonal basis set. Comparison of the densities of states shows similar behavior in the valence band, but the electron density near a defect is less localized with the ABM parameters. It is also found that the projected density of states on the fivefold-coordinated atoms is very close to that on the fourfold-coordinated atoms, while the projected density of states on the threefold-coordinated atoms is distinctly different and has more states in the gap.

James L. Mercer; Jr. and M. Y. Chou

1991-03-15T23:59:59.000Z

414

Understanding Thin Film Structure for the Rational Design of  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Understanding Thin Film Structure for the Rational Design of Understanding Thin Film Structure for the Rational Design of High-performance Organic Semiconductors for Plastic Electronics Organic semiconductors are attracting considerable research interest due to their potential applications in low-cost electronics such as organic light emitting diode (OLED) displays, RF identification tags (RFID), smart cards and electronic paper. The development of p-conjugated materials, which are composed of alternating single and double chemical bonds, are the foundation of these applications. In the past decade research in this field has progressed to the extent that desirable charge transport in the organic semiconductor film in organic thin film transistors (OTFT) can be achieved through molecular design by selective placement of electron-rich, electron-withdrawing, and aromatic groups in different parts of the molecule. Although the electronic properties are easily tuned by molecular design, the molecular packing within the thin film and the film microstructure have a significant influence on the OTFT performance. Despite this importance, this interrelationship between molecular structure, thin film molecular packing and charge transport are only poorly understood.

415

Tungsten oxide (WO{sub 3}) thin films for application in advanced energy systems  

SciTech Connect (OSTI)

Inherent processes in coal gasification plants produce hazardous hydrogen sulfide (H{sub 2}S), which must be continuously and efficiently detected and removed before the fuel is used for power generation. An attempt has been made in this work to fabricate tungsten oxide (WO{sub 3}) thin films by radio-frequency reactive magnetron-sputter deposition. The impetus being the use of WO{sub 3} films for H{sub 2}S sensors in coal gasification plants. The effect of growth temperature, which is varied in the range of 30-500 deg. C, on the growth and microstructure of WO{sub 3} thin films is investigated. Characterizations made using scanning electron microscopy (SEM) and x-ray diffraction (XRD) indicate that the effect of temperature is significant on the microstructure of WO{sub 3} films. XRD and SEM results indicate that the WO{sub 3} films grown at room temperature are amorphous, whereas films grown at higher temperatures are nanocrystalline. The average grain-size increases with increasing temperature. WO{sub 3} films exhibit smooth morphology at growth temperatures {<=}300 deg. C while relatively rough at >300 deg. C. The analyses indicate that the nanocrystalline WO{sub 3} films grown at 100-300 deg. C could be the potential candidates for H{sub 2}S sensor development for application in coal gasification systems.

Gullapalli, S. K.; Vemuri, R. S.; Manciu, F. S.; Enriquez, J. L.; Ramana, C. V. [Department of Mechanical Engineering, University of Texas at El Paso, El Paso, Texas 79968 (United States); Department of Physics, University of Texas at El Paso, El Paso, Texas 79968 (United States); Department of Mechanical Engineering, University of Texas at El Paso, El Paso, Texas 79968 (United States)

2010-07-15T23:59:59.000Z

416

E-Print Network 3.0 - amorphous silicon oxynitride Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

poly-silicon... and Insulators SiO2 Si3N4 Conductors Poly-Silicon (doped and undoped) Tungsten Copper 12;HarvardFabrication2... Single Crystal Silicon SiO2 deposition...

417

An apparatus for the study of superconductivity and electron transport properties of amorphous metals  

E-Print Network [OSTI]

Properties of Amorphous Metals. (August 1987) Hwa Sun Stalnaker, B. S. , Sam Houston State University Chairman of Advisory Conunittee: Dr. Donald G. Naugle An apparatus for studying superconductivity and electron transport prop- erties such as electrical... and electr?deposition usually yield thin films, and the liquid quenching method yields thicker foils. Solid state reaction has been used to pri&duce thin films, powders and fi&ils, but is restricteil t? only a few alloys. The production of amorphous metals...

Stalnaker, Hwa Sun

2012-06-07T23:59:59.000Z

418

Guided Self-Assembly of Gold Thin Films  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Guided Self-Assembly of Gold Thin Films Print Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of science. If nanoparticles could be coaxed into routinely assembling themselves into predictable complex structures and hierarchical patterns, devices could be mass-produced that are one thousand times smaller than today's microtechnologies. Berkeley Lab and UC Berkeley scientists have made progress toward this goal, successfully directing the self--assembly of nanoparticles into device-ready thin films, which have potential applications in fields ranging from computer memory storage to energy harvesting and storage, from catalysis to light management, and into the emerging new field of plasmonics.

419

Guided Self-Assembly of Gold Thin Films  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Guided Self-Assembly of Gold Thin Films Print Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of science. If nanoparticles could be coaxed into routinely assembling themselves into predictable complex structures and hierarchical patterns, devices could be mass-produced that are one thousand times smaller than today's microtechnologies. Berkeley Lab and UC Berkeley scientists have made progress toward this goal, successfully directing the self--assembly of nanoparticles into device-ready thin films, which have potential applications in fields ranging from computer memory storage to energy harvesting and storage, from catalysis to light management, and into the emerging new field of plasmonics.

420

Guided Self-Assembly of Gold Thin Films  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Guided Self-Assembly of Gold Thin Films Print Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of science. If nanoparticles could be coaxed into routinely assembling themselves into predictable complex structures and hierarchical patterns, devices could be mass-produced that are one thousand times smaller than today's microtechnologies. Berkeley Lab and UC Berkeley scientists have made progress toward this goal, successfully directing the self--assembly of nanoparticles into device-ready thin films, which have potential applications in fields ranging from computer memory storage to energy harvesting and storage, from catalysis to light management, and into the emerging new field of plasmonics.

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Guided Self-Assembly of Gold Thin Films  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Guided Self-Assembly of Gold Thin Films Print Guided Self-Assembly of Gold Thin Films Print Nanoparticles-man-made atoms with unique optical, electrical, and mechanical properties-have become key components in many fields of science. If nanoparticles could be coaxed into routinely assembling themselves into predictable complex structures and hierarchical patterns, devices could be mass-produced that are one thousand times smaller than today's microtechnologies. Berkeley Lab and UC Berkeley scientists have made progress toward this goal, successfully directing the self--assembly of nanoparticles into device-ready thin films, which have potential applications in fields ranging from computer memory storage to energy harvesting and storage, from catalysis to light management, and into the emerging new field of plasmonics.

422

Shape variation of micelles in polymer thin films  

SciTech Connect (OSTI)

The equilibrium properties of block copolymer micelles confined in polymer thin films are investigated using self-consistent field theory. The theory is based on a model system consisting of AB diblock copolymers and A homopolymers. Two different methods, based on the radius of gyration tensor and the spherical harmonics expansion, are used to characterize the micellar shape. The results reveal that the morphology of micelles in thin films depends on the thickness of the thin films and the selectivity of the confining surfaces. For spherical (cylindrical) micelles, the spherical (cylindrical) symmetry is broken by the presence of the one-dimensional confinement, whereas the top-down symmetry is broken by the selectivity of the confining surfaces. Morphological transitions from spherical or cylindrical micelles to cylinders or lamella are predicted when the film thickness approaches the micellar size.

Zhou, Jiajia, E-mail: zhou@uni-mainz.de; Shi, An-Chang, E-mail: shi@mcmaste.ca [Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1 (Canada)] [Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1 (Canada)

2014-01-14T23:59:59.000Z

423

Biocompatibility of Pristine Graphene Monolayers, Nanosheets and Thin Films  

E-Print Network [OSTI]

There is an increasing interest to develop nanoscale biocompatible graphene structures due to their desirable physicochemical properties, unlimited application opportunities and scalable production. Here we report the preparation, characterization and biocompatibility assessment of novel graphene flakes and their enabled thin films suitable for a wide range of biomedical and electronic applications. Graphene flakes were synthesized by a chemical vapour deposition method or a liquid-phase exfoliation procedure and then thin films were prepared by transferring graphene onto glass coverslips. Raman spectroscopy and transmission electron microscopy confirmed a predominantly monolayer and a high crystalline quality formation of graphene. The biocompatibility assessment of graphene thin films and graphene flakes was performed using cultured human lung epithelial cell line A549 employing a multimodal approach incorporating automated imaging, high content screening, real-time impedance sensing in combination with bio...

Conroy, Jennifer; Smith, Ronan J; Rezvani, Ehsan; Duesberg, Georg S; Coleman, Jonathan N; Volkov, Yuri

2014-01-01T23:59:59.000Z

424

E-Print Network 3.0 - amorphous silicon carbide Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

50, mai 1989 Summary: revetementdans le substrat. Abstract - Cuttingtools made of A1203+TiC, silicon nitride,carbide, and stabi- lized... with Tic, silicon nitride,...

425

A review on plasma-assisted VLS synthesis of silicon nanowires and radial junction solar cells  

Science Journals Connector (OSTI)

Incorporation of nanostructures is a recent trend in the photovoltaic community, aimed at improving light absorption and consequently cell efficiency. In this regard, semiconductor nanowires provide an attractive research platform for a new generation of cost-effective and efficient solar cells. Thanks to their unique geometry, silicon nanowires enhance light trapping and anti-reflection effects by means of multiple scattering between individual nanowires, and by coupling the light into confined eigenmodes over a broad range of the solar spectrum. Moreover, radial junction solar cells built around nanowires decouple the light absorption and carrier collection directions, which allows for a higher internal field and better carrier collection. Thus, arrays of radial junction solar cells bring advantages of high efficiency with reduced material amount. This is particularly attractive for devices based on hydrogenated amorphous and microcrystalline silicon thin films. In this paper, after reviewing different approaches to fabricate silicon nanowires, we focus on nanowires grown using the plasma-assisted vapour–liquid–solid method because of the simplicity and compatibility with current silicon thin-film technology. Their application to a-Si?:?H based radial junction solar cells has already resulted in ~8% of stable devices with an absorber layer thickness of only 100 nm. Moreover, current challenges and perspectives such as the use of a microcrystalline silicon absorber are also reviewed.

Soumyadeep Misra; Linwei Yu; Wanghua Chen; Martin Foldyna; Pere Roca i Cabarrocas

2014-01-01T23:59:59.000Z

426

Fabrication of polycrystalline thin films by pulsed laser processing  

DOE Patents [OSTI]

A method is disclosed for fabricating polycrystalline thin films on low-temperature (or high-temperature) substrates which uses processing temperatures that are low enough to avoid damage to the substrate, and then transiently heating select layers of the thin films with at least one pulse of a laser or other homogenized beam source. The pulse length is selected so that the layers of interest are transiently heated to a temperature which allows recrystallization and/or dopant activation while maintaining the substrate at a temperature which is sufficiently low to avoid damage to the substrate. This method is particularly applicable in the fabrication of solar cells. 1 fig.

Mitlitsky, F.; Truher, J.B.; Kaschmitter, J.L.; Colella, N.J.

1998-02-03T23:59:59.000Z

427

Fabrication of polycrystalline thin films by pulsed laser processing  

DOE Patents [OSTI]

A method for fabricating polycrystalline thin films on low-temperature (or high-temperature) substrates which uses processing temperatures that are low enough to avoid damage to the substrate, and then transiently heating select layers of the thin films with at least one pulse of a laser or other homogenized beam source. The pulse length is selected so that the layers of interest are transiently heated to a temperature which allows recrystallization and/or dopant activation while maintaining the substrate at a temperature which is sufficiently low to avoid damage to the substrate. This method is particularly applicable in the fabrication of solar cells.

Mitlitsky, Fred (Livermore, CA); Truher, Joel B. (San Rafael, CA); Kaschmitter, James L. (Pleasanton, CA); Colella, Nicholas J. (Livermore, CA)

1998-02-03T23:59:59.000Z

428

Method of improving field emission characteristics of diamond thin films  

DOE Patents [OSTI]

A method of preparing diamond thin films with improved field emission properties. The method includes preparing a diamond thin film on a substrate, such as Mo, W, Si and Ni. An atmosphere of hydrogen (molecular or atomic) can be provided above the already deposited film to form absorbed hydrogen to reduce the work function and enhance field emission properties of the diamond film. In addition, hydrogen can be absorbed on intergranular surfaces to enhance electrical conductivity of the diamond film. The treated diamond film can be part of a microtip array in a flat panel display.

Krauss, Alan R. (Naperville, IL); Gruen, Dieter M. (Downer Grove, IL)

1999-01-01T23:59:59.000Z

429

Method of improving field emission characteristics of diamond thin films  

DOE Patents [OSTI]

A method of preparing diamond thin films with improved field emission properties is disclosed. The method includes preparing a diamond thin film on a substrate, such as Mo, W, Si and Ni. An atmosphere of hydrogen (molecular or atomic) can be provided above the already deposited film to form absorbed hydrogen to reduce the work function and enhance field emission properties of the diamond film. In addition, hydrogen can be absorbed on intergranular surfaces to enhance electrical conductivity of the diamond film. The treated diamond film can be part of a microtip array in a flat panel display. 3 figs.

Krauss, A.R.; Gruen, D.M.

1999-05-11T23:59:59.000Z

430

Formation and ferromagnetic properties of FeSi thin films  

SciTech Connect (OSTI)

In this work, the growth and ferromagnetic properties of {epsilon}-FeSi thin film on Si(100) substrate prepared by molecular beam epitaxy are reported. The inter-diffusion of Fe layer on Si(100) substrate at 600 Degree-Sign C results in polycrystalline {epsilon}-FeSi layer. The determined activation energy was 0.044 eV. The modified magnetism from paramagnetic in bulk to ferromagnetic states in {epsilon}-FeSi thin films was observed. The saturated magnetization and coercive field of {epsilon}-FeSi film are 4.6 emu/cm{sup 3} and 29 Oe at 300 K, respectively.

Shin, Yooleemi; Anh Tuan, Duong; Hwang, Younghun; Viet Cuong, Tran; Cho, Sunglae [Department of Physics, University of Ulsan, Ulsan 680-749 (Korea, Republic of)

2013-05-07T23:59:59.000Z

431

Two-color Laser Desorption of Nanostructured MgO Thin Films....  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Two-color Laser Desorption of Nanostructured MgO Thin Films. Two-color Laser Desorption of Nanostructured MgO Thin Films. Abstract: Neutral magnesium atom emission from...

432

Initiated chemical vapor deposition of polymeric thin films : mechanism and applications  

E-Print Network [OSTI]

Initiated chemical vapor deposition (iCVD) is a novel technique for depositing polymeric thin films. It is able to deposit thin films of application-specific polymers in one step without using any solvents. Its uniqueness ...

Chan, Kelvin, Ph. D. Massachusetts Institute of Technology

2005-01-01T23:59:59.000Z

433

Trend Detection on Thin-Film Solar Cell Technology Using Cluster Analysis and Modified Data Crystallization  

Science Journals Connector (OSTI)

Thin-film solar cell, one of green energies, is growing ... . To detect the potential trends of this technology is essential for companies and relevant industries ... patterns, the potential trends of thin-film solar

Tzu-Fu Chiu; Chao-Fu Hong; Yu-Ting Chiu

2010-01-01T23:59:59.000Z

434

Thin-film solar cells: review of materials, technologies and commercial status  

Science Journals Connector (OSTI)

As apparent from Table 1..., showing the production volume for different manufacturers of these thin-film technologies over the past 3 years, rapidly-growing ... are also increasing rapidly, the thin-film technologies

Martin A. Green

2007-10-01T23:59:59.000Z

435

Quench Properties and Fault Current Limiters of YBCO Thin-Film Superconductors  

Science Journals Connector (OSTI)

We measured the current dependence of quench propagation velocities in strip-shaped YBCO thin films and the current-limiting properties of fault current limiters consisting of a YBCO thin film and ... -300 cm/sec...

Hiroshi Kubota; Yuki Kudo; Mutsuki Yamazaki…

1998-01-01T23:59:59.000Z

436

E-Print Network 3.0 - advanced thin film Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

half of all glass... cells by absorbing light within a specific wavelength. Today's thin-film solar cells could not function... , but static, layer of a thin-film pho- tovoltaic...

437

Influence of samaria doping on the resistance of ceria thin films...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

doping on the resistance of ceria thin films and its implications to the planar oxygen sensing devices. Influence of samaria doping on the resistance of ceria thin films and...

438

Junction Evolution During Fabrication of CdS/CdTe Thin-film PV Solar Cells (Presentation)  

SciTech Connect (OSTI)

Discussion of the formation of CdTe thin-film PV junctions and optimization of CdTe thin-film PV solar cells.

Gessert, T. A.

2010-09-01T23:59:59.000Z

439

Sharp semiconductor-to-metal transition of VO{sub 2} thin films on glass substrates  

SciTech Connect (OSTI)

Outstanding phase transition properties of vanadium dioxide (VO{sub 2}) thin films on amorphous glass were achieved and compared with the ones grown on c-cut sapphire and Si (111) substrates, all by pulsed laser deposition. The films on glass substrate exhibit a sharp semiconductor-to-metal transition (?4.3?°C) at a near bulk transition temperature of ?68.4?°C with an electrical resistance change as high as 3.2?×?10{sup 3} times. The excellent phase transition properties of the films on glass substrate are correlated with the large grain size and low defects density achieved. The phase transition properties of VO{sub 2} films on c-cut sapphire and Si (111) substrates were found to be limited by the high defect density.

Jian, Jie; Chen, Aiping [Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843-3128 (United States); Zhang, Wenrui [Material Science and Engineering Program, Texas A and M University, College Station, Texas 77843-3128 (United States); Wang, Haiyan, E-mail: wangh@ece.tamu.edu [Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843-3128 (United States); Material Science and Engineering Program, Texas A and M University, College Station, Texas 77843-3128 (United States)

2013-12-28T23:59:59.000Z

440

Simple method for preparing hydrogenated amorphous silicon films by chemical vapor deposition at atmospheric pressure  

SciTech Connect (OSTI)

An inexpensive one-step method is presented for fabricating hydrogenated amorphous silicon (a-Si:H) films with good photovoltaic properties using chemical vapor deposition (CVD) from a mixture of silane, disilane, trisilane, and higher polysilanes in hydrogen at one atmosphere total pressure. The gas mixture is generated by the action of dilute acid on magnesium silicide and used immediately in the CVD process. Thus, elaborate techniques for handling, transporting or storing the pyrophoric polysilanes are avoided. In addition, the method requires no expensive vacuum or electrical equipment. The conditions necessary for high (approx. =10%) hydrogen incorporation and very high deposition rates (50-100 A/sec) are explained. Experimental parameters are explained and properties as a function of these parameters are shown. The measurements include hydrogen content, optical, electrical and photovoltaic properties of the a-Si:H films. A chemical kinetic model is presented for this and other silane and polysilane CVD systems between about 400 and 600/sup 0/C. Both homogeneous and heterogeneous reactions are considered. The model is derived from homogeneous gas-phase silane and polysilane chemistry and predicts, in agreement with our experiments, that the homogeneous gas-phase chemistry determines the a-Si:H film growth rate under a variety of conditions. The model is sufficiently predictive to be useful in determining appropriate experimental conditions. Stable solar cells are proposed for a-Si:H and fluorine doped tin oxide which can be produced by CVD at very high deposition rates. The unstable a-Si:H/tin oxide interface is eliminated by a very thin layer of titanium nitride and oxide between the a-Si:H and tin oxide.

Ellis, F.B. Jr.

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Structural, optical, and spin properties of hydrogenated amorphous silicon?germanium alloys  

Science Journals Connector (OSTI)

We report on a detailed study of structural and electronic properties of hydrogenated amorphous silicon?germanium alloys deposited by rf glow discharge from SiH4 and GeH4 in a diode reactor. The chemical composition of the alloys is related to the deposition conditions with special emphasis on preferential incorporation of Ge into the solid phase and on the role of inert dilutant gases. Hydrogen bonding in the alloys is investigated with nuclear magnetic resonance and vibrational (Raman and infrared) spectroscopy. The optical properties of a?SiGe:H samples deposited under optimal conditions are analyzed with the help of subgap absorption measurements and band?tail luminescence for the entire range of alloy composi?tions. A large part of the article describes an investigation of the electron?spin?resonance response of undoped alloys. The spin density associated with dangling bond defects localized on Si and Ge atoms has been measured as a function of alloy composition for optimized material. In addition the dependence of the two defect densities on the detailed deposition conditions (rf power substrate temperature and dilution) has been determined in a systematic way for alloys deposited from a plasma with a fixed SiH4/GeH4ratio. The results of this study especially the preferential creation of Gedangling bonds are discussed in the context of our structural data. Furthermore spin resonance is employed to investigate the light?induced degradation (Staebler–Wronski effect) of a?SiGe:H. Finally the changes of the spin?resonance spectra of a?Si0.7Ge0.3 :H upon substitutional doping with phosphorus and boron have been obtained experimentally and are used to construct a model for the electronic density of states in this material.

M. Stutzmann; R. A. Street; C. C. Tsai; J. B. Boyce; S. E. Ready

1989-01-01T23:59:59.000Z

442

Propagating Nanocavity-Enhanced Rapid Crystallization of Silicon Thin Films  

Science Journals Connector (OSTI)

This work was partially supported by MRSEC Program of the National Science Foundation under Award Number DMR-0819885, NSF Grant DMR-0705675 and by the Xcel Energy Renewable Development Fund under Grant RD-3-25. ...

Andrew J. Wagner; Curtis M. Anderson; Jason N. Trask; Lin Cui; Alexander Chov; K. Andre Mkhoyan; Uwe R. Kortshagen

2013-10-29T23:59:59.000Z

443

Development of FeNiMoB thin film materials for microfabricated magnetoelastic sensors  

SciTech Connect (OSTI)

Metglas{sup TM} 2826MB foils of 25-30 {mu}m thickness with the composition of Fe{sub 40}Ni{sub 38}Mo{sub 4}B{sub 18} have been used for magnetoelastic sensors in various applications over many years. This work is directed at the investigation of {approx}3 {mu}m thick iron-nickel-molybdenum-boron (FeNiMoB) thin films that are intended for integrated microsystems. The films are deposited on Si substrate by co-sputtering of iron-nickel (FeNi), molybdenum (Mo), and boron (B) targets. The results show that dopants of Mo and B can significantly change the microstructure and magnetic properties of FeNi materials. When FeNi is doped with only Mo its crystal structure changes from polycrystalline to amorphous with the increase of dopant concentration; the transition point is found at about 10 at. % of Mo content. A significant change in anisotropic magnetic properties of FeNi is also observed as the Mo dopant level increases. The coercivity of FeNi films doped with Mo decreases to a value less than one third of the value without dopant. Doping the FeNi with B together with Mo considerably decreases the value of coercivity and the out-of-plane magnetic anisotropy properties, and it also greatly changes the microstructure of the material. In addition, doping B to FeNiMo remarkably reduces the remanence of the material. The film material that is fabricated using an optimized process is magnetically as soft as amorphous Metglas{sup TM} 2826MB with a coercivity of less than 40 Am{sup -1}. The findings of this study provide us a better understanding of the effects of the compositions and microstructure of FeNiMoB thin film materials on their magnetic properties.

Liang Cai; Gooneratne, Chinthaka; Cha, Dongkyu; Chen Long; Kosel, Jurgen [Computer Electrical and Mathematical Sciences and Engineering, King Abdullah University of Science and Technology, 4700 KAUST, Thuwal 23955 (Saudi Arabia); Gianchandani, Yogesh [Department of Electrical Engineering and Computer Science, 1301 Beal Ave., University of Michigan, Ann Arbor, Michigan 48109 (United States)

2012-12-01T23:59:59.000Z

444

Thin-film transistors based on p-type Cu{sub 2}O thin films produced at room temperature  

SciTech Connect (OSTI)

Copper oxide (Cu{sub 2}O) thin films were used to produce bottom gate p-type transparent thin-film transistors (TFTs). Cu{sub 2}O was deposited by reactive rf magnetron sputtering at room temperature and the films exhibit a polycrystalline structure with a strongest orientation along (111) plane. The TFTs exhibit improved electrical performance such as a field-effect mobility of 3.9 cm{sup 2}/V s and an on/off ratio of 2x10{sup 2}.

Fortunato, Elvira; Figueiredo, Vitor; Barquinha, Pedro; Elamurugu, Elangovan; Goncalves, Goncalo; Martins, Rodrigo [Departamento de Ciencia dos Materiais, CENIMAT/I3N, Faculdade de Ciencias e Tecnologia, FCT, Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica (Portugal); Barros, Raquel [Departamento de Ciencia dos Materiais, CENIMAT/I3N, Faculdade de Ciencias e Tecnologia, FCT, Universidade Nova de Lisboa and CEMOP-UNINOVA, 2829-516 Caparica (Portugal); Materiais Avancados, INNOVNANO, SA, 7600-095 Aljustrel (Portugal); Park, Sang-Hee Ko; Hwang, Chi-Sun [Electronic and Telecommunications Research Institute, 138 Gajeongro, Yuseong-gu, Daejeon, 305-700 (Korea, Republic of)

2010-05-10T23:59:59.000Z

445

An integrated thin-film thermo-optic waveguide beam deflector Suning Tang,a)  

E-Print Network [OSTI]

An integrated thin-film thermo-optic waveguide beam deflector Suning Tang,a) Bulang Li, and Xinghua for publication 16 February 2000 We have demonstrated the operation of a thin-film thermo-optical beam deflector in a three-layer optical planar waveguide. The fabricated waveguide beam deflector consists of a thin-film Si

Chen, Ray

446

Design and fabrication of photonic crystal thin film photovoltaic cells Guillaume Gomarda,b  

E-Print Network [OSTI]

Design and fabrication of photonic crystal thin film photovoltaic cells Guillaume Gomarda,b , Ounsi of an absorbing planar photonic crystal within a thin film photovoltaic cell. The devices are based on a stack with large areas. Keywords: Photonic crystal, Photovoltaic solar cell, Thin film solar cell, Hydrogenated

Paris-Sud XI, Université de

447

EARTH ABUNDANT MATERIALS FOR HIGH EFFICIENCY HETEROJUNCTION THIN FILM SOLAR CELLS  

E-Print Network [OSTI]

EARTH ABUNDANT MATERIALS FOR HIGH EFFICIENCY HETEROJUNCTION THIN FILM SOLAR CELLS Yun Seog Lee 1; * Corresponding author: buonassisi@mit.edu; ABSTRACT We investigate earth abundant materials for thin- film solar cuprous oxide (Cu2O) as a prototype candidate for investigation as an absorber layer in thin film solar

Ceder, Gerbrand

448

LBIC ANALYSIS OF THIN-FILM POLYCRYSTALLINE SOLAR CELLS James R. Sites and Timothy J. Nagle  

E-Print Network [OSTI]

LBIC ANALYSIS OF THIN-FILM POLYCRYSTALLINE SOLAR CELLS James R. Sites and Timothy J. Nagle Physics response map, was developed and used to map defects in thin-film solar cells [4]. Improvements to the two) measurements are providing a direct link between the spatial non-uniformities inherent in thin-film

Sites, James R.

449

DISSERTATION ELECTRON-REFLECTOR STRATEGY FOR CdTe THIN-FILM SOLAR CELLS  

E-Print Network [OSTI]

DISSERTATION ELECTRON-REFLECTOR STRATEGY FOR CdTe THIN-FILM SOLAR CELLS Submitted by Kuo-Jui Hsiao ELECTRON- REFLECTOR STRATEGY FOR CdTe THIN-FILM SOLAR CELLS BE ACCEPTED AS FULFILLING IN PART REQUIREMENTS SOLAR CELLS The CdTe thin-film solar cell has a large absorption coefficient and high theoretical

Sites, James R.

450

Metal-black scattering centers to enhance light harvesting by thin-film solar cells  

E-Print Network [OSTI]

Metal-black scattering centers to enhance light harvesting by thin-film solar cells Deep Panjwania as scattering centers to increase the effective optical thickness of thin-film solar cells. The particular type. Gold-black was deposited on commercial thin-film solar cells using a thermal evaporator in nitrogen

Peale, Robert E.

451

Transition from Irradiation-Induced Amorphization to Crystallization...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

from Irradiation-Induced Amorphization to Crystallization in Nanocrystalline Silicon Carbide. Transition from Irradiation-Induced Amorphization to Crystallization in...

452

High performance hydrogenated amorphous silicon solar cells made at a high deposition rate by glow discharge of disilane  

SciTech Connect (OSTI)

The deposition rate, electronic and optical properties of hydrogenated amorphous silicon films prepared from rf glow discharge decomposition of disilane (Si/sub 2/H/sub 6/) diluted in helium have been measured. These films show excellent electrical and optical properties and, most importantly, a high deposition rate coupled with satisfactory solar cell application was realized for the first time. At a deposition rate of 11 A/s, 5.47% and 6.5% conversion efficiencies were obtained with a first trial of n-i-p type solar cells deposited on SnO/sub 2//ITO glass and metal substrates, respectively.

Ohashi, Y.; Kenne, J.; Konagai, M.; Takahashi, K.

1983-06-15T23:59:59.000Z

453

Method of preparing thin film polymeric gel electrolytes  

DOE Patents [OSTI]

Novel hybrid thin film electrolyte, based on an organonitrile solvent system, which are compositionally stable, environmentally safe, can be produced efficiently in large quantity and which, because of their high conductivities .apprxeq.10.sup.-3 .OMEGA..sup.-1 cm.sup.-1 are useful as electrolytes for rechargeable lithium batteries.

Derzon, Dora K. (Albuquerque, NM); Arnold, Jr., Charles (Albuquerque, NM)

1997-01-01T23:59:59.000Z

454

Synthesis and Characterization of Functional Nanostructured Zinc Oxide Thin Films  

E-Print Network [OSTI]

.1149/1.2357098, copyright The Electrochemical Society 65 #12;66 reduced environmental impact and a minimum undesirable inter-temperature thin film growth technique has been developed to fabricate a new generation of smart and functional and structural requirements of their applications in gas sensors and solar cells. The rapid photothermal

Chow, Lee

455

Perovskite phase thin films and method of making  

DOE Patents [OSTI]

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

Boyle, Timothy J. (Albuquerque, NM); Rodriguez, Mark A. (Albuquerque, NM)

2000-01-01T23:59:59.000Z

456

Preparation and characterization of TL-based superconducting thin films  

E-Print Network [OSTI]

A simple method for growth of Tl-based superconducting thin films is described. In this method, the precursor was prepared in a vacuum chamber by deposition of Ba, Ca and Cu metals or a Ba-Ca alloy and Cu metal. The precursor was then oxidized...

Wang, Pingshu

2012-06-07T23:59:59.000Z

457

Chemical analysis of thin films at Sandia National Laboratories  

SciTech Connect (OSTI)

The characterization of thin films produced by chemical and physical vapor deposition requires special analytical techniques. When the average compositions of the films are required, dissolution of the thin films and measurement of the concentrations of the solubilized species is the appropriate analytical approach. In this report techniques for the wet chemical analysis of thin films of Si:Al, P/sub 2/O/sub 5/:SiO/sub 2/, B/sub 2/O/sub 3/:SiO/sub 2/, TiB/sub x/ and TaB/sub x/ are described. The analyses are complicated by the small total quantities of these analytes present in the films, the refractory characters of these analytes, and the possibility of interferences from the substrates on which the films are deposited. Etching conditions are described which dissolve the thin films without introducing interferences from the substrates. A chemical amplification technique and inductively coupled plasma atomic emission spectrometry are shown to provide the sensitivity required to measure the small total quantities (micrograms to milligrams) of analytes present. Also the chemical analysis data has been used to calibrate normal infrared absorption spectroscopy to give fast estimates of the phosphorus and/or boron dopant levels in thin SiO/sub 2/ films.

Tallant, D.R.; Taylor, E.L.

1980-05-01T23:59:59.000Z

458

Thin crystalline silicon solar cells based on epitaxial films grown at 165C by RF PECVD  

E-Print Network [OSTI]

1 Thin crystalline silicon solar cells based on epitaxial films grown at 165°C by RF PECVD Romain temperatures. Keywords : Low temperature, epitaxy, PECVD, Si thin film, Solar cell hal-00749873,version1-25Nov shortage until 2010. Research on epitaxial growth for thin film crystalline silicon solar cells has gained

459

Silicon Solar Cell Light-Trapping Using Defect Mode Photonic Kelsey A. Whitesell*a  

E-Print Network [OSTI]

Silicon Solar Cell Light-Trapping Using Defect Mode Photonic Crystals Kelsey A. Whitesell to enhance performance of thin film solar cells because of their unique ability to control light. We show for light trapping in thin film photovoltaics. Keywords: photonic crystals, defect, silicon, solar cell

Atwater, Harry

460

Synthesis, structural and electrochemical properties of electron beam evaporated V{sub 2}O{sub 5} thin films  

SciTech Connect (OSTI)

Vanadium pentoxide is one of the most promising cathode materials because it offers high energy density, low cost, low toxicity over the other cathode materials. Its layered and open structure makes this material in thin film form well suited for electro-chemical insertion reactions with the Li ions. In the present investigation, V{sub 2}O{sub 5} thin films have been prepared by electron beam evaporation technique on gold coated silicon substrates maintained at a substrate temperature of 250 Degree-Sign C in an oxygen partial pressure of 2 Multiplication-Sign 10{sup -4} mbar. The XRD patterns exhibited three predominant diffraction peaks corresponding to (200) (001) and (400) planes of orthorhombic phase of V{sub 2}O{sub 5} with P{sub mnm} space group. The electrochemical characteristics of V{sub 2}O{sub 5} thin films with thickness of 600 nm were examined in non-aqueous region. The film exhibited step wise discharge with two plateaus. The as-deposited film delivered a discharge capacity of 70 {mu}Ah/(cm{sup 2}-{mu}m) at a current density of 30 {mu}A/cm{sup 2}. Annealing of these films at 450 Degree-Sign C exhibited a better discharge capacity of 90 {mu}Ah/(cm{sup 2}-{mu}m).

Hussain, O. M.; Rosaiah, P. [Thin Film Laboratory, Department of Physics, Sri Venkateswara University, Tirupati-517 502 (India)

2012-06-25T23:59:59.000Z

Note: This page contains sample records for the topic "thin-film amorphous silicon" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Theoretical simulations of protective thin film Fabry-Pérot filters for integrated optical elements of diode pumped alkali lasers (DPAL)  

SciTech Connect (OSTI)

The lifetime of Diode-Pumped Alkali Lasers (DPALs) is limited by damage initiated by reaction of the glass envelope of its gain medium with rubidium vapor. Rubidium is absorbed into the glass and the rubidium cations diffuse through the glass structure, breaking bridging Si-O bonds. A damage-resistant thin film was developed enhancing high-optical transmission at natural rubidium resonance input and output laser beam wavelengths of 780 nm and 795 nm, while protecting the optical windows of the gain cell in a DPAL. The methodology developed here can be readily modified for simulation of expected transmission performance at input pump and output laser wavelengths using different combination of thin film materials in a DPAL. High coupling efficiency of the light through the gas cell was accomplished by matching the air-glass and glass-gas interfaces at the appropriate wavelengths using a dielectric stack of high and low index of refraction materials selected to work at the laser energies and protected from the alkali metal vapor in the gain cell. Thin films as oxides of aluminum, zirconium, tantalum, and silicon were selected allowing the creation of Fabry-Perot optical filters on the optical windows achieving close to 100% laser transmission in a solid optic combination of window and highly reflective mirror. This approach allows for the development of a new whole solid optic laser.

Quarrie, L., E-mail: Lindsay.Quarrie@l-3com.com, E-mail: lindsay.o.quarrie@gmail.com [New Mexico Institute of Mining and Technology, Department of Materials Engineering, 801 LeRoy Place, Socorro, NM 87801 (United States); Air Force Research Laboratory, AFRL/RDLC Laser CoE, 3550 Aberdeen Avenue SE, Kirtland AFB, NM 87117-5776 (United States)

2014-09-15T23:59:59.000Z

462

Manipulating hybrid structures of polymer/a-Si for thin film solar cells  

SciTech Connect (OSTI)

A series of uniform polymer/amorphous silicon hybrid structures have been fabricated by means of solution-casting for polymer and radio frequency excited plasma enhanced chemical vapour deposition for amorphous silicon (a-Si:H). Poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) functioned as a photoactive donor, while the silicon layer acted as an acceptor. It is found that matching the hole mobility of the polymer to the electron mobility of amorphous silicon is critical to improve the photovoltaic performance from hybrid cells. A three-layer p-i-n structure of ITO/PEDOT:PSS(200?nm)/i-Si(450?nm)/n-Si(200?nm)/Al with a power conversion efficiency of 4.78% under a standard test condition was achieved.

Peng, Ying; He, Zhiqun, E-mail: zhqhe@bjtu.edu.cn, E-mail: J.I.B.Wilson@hw.ac.uk; Zhang, Zhi; Liang, Chunjun [Key Laboratory of Luminescence and Optical Information, Ministry of Education, Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing 100044 (China); Diyaf, Adel; Ivaturi, Aruna; Wilson, John I. B., E-mail: zhqhe@bjtu.edu.cn, E-mail: J.I.B.Wilson@hw.ac.uk [SUPA, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)

2014-03-10T23:59:59.000Z

463

Institute of Photo Electronic Thin Film Devices and Technology of Nankai  

Open Energy Info (EERE)

Electronic Thin Film Devices and Technology of Nankai Electronic Thin Film Devices and Technology of Nankai University Jump to: navigation, search Name Institute of Photo-Electronic Thin Film Devices and Technology of Nankai University Place Tianjin Municipality, China Zip 300071 Sector Solar Product A thin-film solar cell research institute in China. References Institute of Photo-Electronic Thin Film Devices and Technology of Nankai University[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Institute of Photo-Electronic Thin Film Devices and Technology of Nankai University is a company located in Tianjin Municipality, China . References ↑ "Institute of Photo-Electronic Thin Film Devices and Technology of Nankai University"

464

Co-sputtering yttrium into hafnium oxide thin films to produce ferroelectric properties  

SciTech Connect (OSTI)

Thin film capacitors were fabricated by sputtering TiN-Y doped HfO{sub 2}-TiN stacks on silicon substrates. Yttrium was incorporated into the HfO{sub 2} layers by simultaneously sputtering from Y{sub 2}O{sub 3} and HfO{sub 2} sources. Electric polarization and relative permittivity measurements yield distinct ferroelectric properties as a result of low yttrium dopant concentrations in the range of 0.9-1.9 mol. %. Grazing incidence x-ray diffraction measurements show the formation of an orthorhombic phase in this range. Compared to atomic layer deposition films, the highest remanent polarization and the highest relative permittivity were obtained at significantly lower doping concentrations in these sputtered films.

Olsen, T. [NaMLab gGmbH, 01187 Dresden (Germany); Department of Electrical and Computer Engineering, University of Alberta, Edmonton T6G 2V4 (Canada); Schroeder, U.; Mueller, S.; Krause, A.; Martin, D.; Singh, A. [NaMLab gGmbH, 01187 Dresden (Germany); Mueller, J. [Fraunhofer CNT, 01099 Dresden (Germany); Geidel, M. [Institute of Semiconductors and Microsystems, Technische Universitaet Dresden, 01062 Dresden (Germany); Mikolajick, T. [NaMLab gGmbH, 01187 Dresden (Germany); Institute of Semiconductors and Microsystems, Technische Universitaet Dresden, 01062 Dresden (Germany)

2012-08-20T23:59:59.000Z

465

Spin Coated Plasmonic Nanoparticle Interfaces for Photocurrent Enhancement in Thin Film Si Solar Cells  

E-Print Network [OSTI]

Nanoparticle (NP) arrays of noble metals strongly absorb light in the visible to infrared wavelengths through resonant interactions between the incident electromagnetic field and the metal's free electron plasma. Such plasmonic interfaces enhance light absorption and photocurrent in solar cells. We report a cost effective and scalable room temperature/pressure spin-coating route to fabricate broadband plasmonic interfaces consisting of silver NPs. The NP interface yields photocurrent enhancement (PE) in thin film silicon devices by up to 200% which is significantly greater than previously reported values. For coatings produced from Ag nanoink containing particles with average diameter of 40 nm, an optimal NP surface coverage of 7% was observed. Scanning electron microscopy of interface morphologies revealed that for low surface coverage, particles are well-separated, resulting in broadband PE. At higher surface coverage, formation of particle strings and clusters caused red-shifting of the PE peak and a narro...

Israelowitz, Miriam; Cong, Tao; Sureshkumar, Radhakrishna

2013-01-01T23:59:59.000Z

466

Outdoor Performance of a Thin-Film Gallium-Arsenide Photovoltaic Module  

SciTech Connect (OSTI)

We deployed a 855 cm2 thin-film, single-junction gallium arsenide (GaAs) photovoltaic (PV) module outdoors. Due to its fundamentally different cell technology compared to silicon (Si), the module responds differently to outdoor conditions. On average during the test, the GaAs module produced more power when its temperature was higher. We show that its maximum-power temperature coefficient, while actually negative, is several times smaller in magnitude than that of a Si module used for comparison. The positive correlation of power with temperature in GaAs is due to temperature-correlated changes in the incident spectrum. We show that a simple correction based on precipitable water vapor (PWV) brings the photocurrent temperature coefficient into agreement with that measured by other methods and predicted by theory. The low operating temperature and small temperature coefficient of GaAs give it an energy production advantage in warm weather.

Silverman, T. J.; Deceglie, M. G.; Marion, B.; Cowley, S.; Kayes, B.; Kurtz, S.

2013-06-01T23:59:59.000Z

467

Molecular doping for control of gate bias stress in organic thin film transistors  

SciTech Connect (OSTI)

The key active devices of future organic electronic circuits are organic thin film transistors (OTFTs). Reliability of OTFTs remains one of the most challenging obstacles to be overcome for broad commercial applications. In particular, bias stress was identified as the key instability under operation for numerous OTFT devices and interfaces. Despite a multitude of experimental observations, a comprehensive mechanism describing this behavior is still missing. Furthermore, controlled methods to overcome these instabilities are so far lacking. Here, we present the approach to control and significantly alleviate the bias stress effect by using molecular doping at low concentrations. For pentacene and silicon oxide as gate oxide, we are able to reduce the time constant of degradation by three orders of magnitude. The effect of molecular doping on the bias stress behavior is explained in terms of the shift of Fermi Level and, thus, exponentially reduced proton generation at the pentacene/oxide interface.

Hein, Moritz P., E-mail: hein@iapp.de; Lüssem, Björn; Jankowski, Jens; Tietze, Max L.; Riede, Moritz K. [Institut für Angewandte Photophysik, Technische Universität Dresden, George-Bähr-Straße 1, 01069 Dresden (Germany)] [Institut für Angewandte Photophysik, Technische Universität Dresden, George-Bähr-Straße 1, 01069 Dresden (Germany); Zakhidov, Alexander A. [Fraunhofer COMEDD, Maria-Reiche-Str. 2, 01109 Dresden (Germany)] [Fraunhofer COMEDD, Maria-Reiche-Str. 2, 01109 Dresden (Germany); Leo, Karl [Institut für Angewandte Photophysik, Technische Universität Dresden, George-Bähr-Straße 1, 01069 Dresden (Germany) [Institut für Angewandte Photophysik, Technische Universität Dresden, George-Bähr-Straße 1, 01069 Dresden (Germany); Fraunhofer COMEDD, Maria-Reiche-Str. 2, 01109 Dresden (Germany)

2014-01-06T23:59:59.000Z

468

In–Ga–Zn–O thin film transistor with HfO{sub 2} gate insulator prepared using various O{sub 2}/(Ar + O{sub 2}) gas ratios  

SciTech Connect (OSTI)

We have investigated the effect of the deposition of an HfO{sub 2} thin film as a gate insulator with different O{sub 2}/(Ar + O{sub 2}) gas ratios using RF magnetron sputtering. The HfO{sub 2} thin film affected the device performance of amorphous indium–gallium–zinc oxide transistors. The performance of the fabricated transistors improved monotonously with increasing O{sub 2}/(Ar + O{sub 2}) gas ratio: at a ratio of 0.35, the field effect mobility of the amorphous InGaZnO thin film transistors was improved to 7.54 cm{sup 2}/(V s). Compared to those prepared with an O{sub 2}/(Ar + O{sub 2}) gas ratio of 0.05, the field effect mobility of the amorphous InGaZnO thin film transistors was increased to 1.64 cm{sup 2}/(V s) at a ratio of 0.35. This enhancement in the field effect mobility was attributed to the reduction of the root mean square roughness of the gate insulator layer, which might result from the trap states and surface scattering of the gate insulator layer at the lower O{sub 2}/(Ar + O{sub 2}) gas ratio.

Jo, Young Je [WCU Department of Printed Electronics, Sunchon National University, Chonnam 540-742 (Korea, Republic of)] [WCU Department of Printed Electronics, Sunchon National University, Chonnam 540-742 (Korea, Republic of); Lee, In-Hwan [School of Advanced Materials Engineering, Chonbuk National University, Chonju 561-756 (Korea, Republic of)] [School of Advanced Materials Engineering, Chonbuk National University, Chonju 561-756 (Korea, Republic of); Kwak, Joon Seop, E-mail: jskwak@sunchon.ac.kr [WCU Department of Printed Electronics, Sunchon National University, Chonnam 540-742 (Korea, Republic of)

2012-10-15T23:59:59.000Z

469

E-Print Network 3.0 - amorphous silicon flat Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Cells n Sensors n Flat Panels n IC Circuits... and low-performance, low-cost amorphous film solar cells. n Potential for high ... Source: Los Alamos National Laboratory,...

470

New Approaches for Passivation of Crystalline and Amorphous Silicon: Cooperative Research and Development Final Report, CRADA Number CRD-09-351  

SciTech Connect (OSTI)

New approaches of passivating crystalline, multicrystalline, and amorphous silicon will be explored. These will include the use of aqueous solution of KCN and a proprietary composition formulated by Mallinckrodt Baker, Inc. The surface passivation will be compared with that provided by an iodine-ethanol solution, and bulk passivation will be compared with that of H-passivation obtained by silicon nitride, in a fire-through process.

Sopori, B.

2012-09-01T23:59:59.000Z

471

Kinetics of hydrogen desorption in surface-limited thin-film growth of SiGe alloys  

SciTech Connect (OSTI)

The kinetics of hydrogen desorption in surface-limited thin-film growth of SiGe alloys from binary mixtures of disilane and digermane was investigated by surface differential reflectance. The hydrogen desorption process from the alloy surface was found to consist of two components. Both components are thermally activated, but the activation energies appear to equal neither the hydrogen desorption energy from pure silicon nor that from pure germanium surfaces. We suggest that the two components represent Ge- and Si-mediated hydrogen desorption, with the former being more rapid than the latter.

Sharp, J.W. (Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996 (United States)); Eres, G. (Oak Ridge National Laboratory, P. O. Box 2008, Solid State Division, Bldg. 2000 MS 6056, Oak Ridge, Tennessee 37831-6056 (United States))

1993-05-31T23:59:59.000Z

472

E-Print Network 3.0 - amorphous silicon-based solar Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

University of Toledo Collection: Renewable Energy 3 21st European Photovoltaic Solar Energy Conference (2006) DEFECT DENSITY IN SILICON HETEROJUNCTIONS Summary: voltage, V , and...

473

E-Print Network 3.0 - amorphous silicon nitride Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

nitride, aluminium oxide, titanium nitride are promising materials for the high... of powder analysis made by the following processes: - Preparation of silicon nitride by...

474

Organic thin film prehistory: looking towards solution phase aggregation |  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Organic thin film prehistory: looking towards solution phase aggregation Organic thin film prehistory: looking towards solution phase aggregation Wednesday, November 6, 2013 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Christopher Tassone, SSRL Polymer bulk heterojunction (BHJ) solar cells have attracted significant attention in industry and academia because of their potential for achieving large-area, light-weight, and flexible photovoltaic devices through cost-effective solution deposition techniques. These devices consist of a blend of an absorbing polymer and an electron accepting fullerene, the molecular packing and phase segregation of which heavily influence power conversion efficiency by effecting important processes such as exciton splitting, charge transport, and recombination. Understanding and utilization of molecular interactions to predicatively control the

475

Engineering Thin-Film Oxide Interfaces | Advanced Photon Source  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Novel Materials Become Multifunctional at the Ultimate Quantum Limit Novel Materials Become Multifunctional at the Ultimate Quantum Limit Outsmarting Flu Viruses How Lead-Free Solder (Mis)Behaves under Stress Dynamics of Polymer Chains Atop Different Materials Priming the Pump in the Fight against Drug-Resistant Tuberculosis Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed Engineering Thin-Film Oxide Interfaces NOVEMBER 12, 2012 Bookmark and Share LAO thin films on STO substrates are depicted in the top schematics (LAO indicated by blue spheres, STO by green spheres). The top left-hand panel demonstrates a chemically broad interface resulting from conventional growth in a low pressure oxygen environment. In contrast, the top

476

Thin film battery and method for making same  

DOE Patents [OSTI]

Described is a thin-film battery, especially a thin-film microbattery, and a method for making same having application as a backup or primary integrated power source for electronic devices. The battery includes a novel electrolyte which is electrochemically stable and does not react with the lithium anode and a novel vanadium oxide cathode Configured as a microbattery, the battery can be fabricated directly onto a semiconductor chip, onto the semiconductor die or onto any portion of the chip carrier. The battery can be fabricated to any specified size or shape to meet the requirements of a particular application. The battery is fabricated of solid state materials and is capable of operation between -15.degree. C. and 150.degree. C.

Bates, John B. (Oak Ridge, TN); Dudney, Nancy J. (Knoxville, TN); Gruzalski, Greg R. (Oak Ridge, TN); Luck, Christopher F. (Knoxville, TN)

1994-01-01T23:59:59.000Z

477

TI--CR--AL--O thin film resistors  

DOE Patents [OSTI]

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 <1 .mu.m thick. The film resistivity can be discretely selected through control of the target composition and the deposition parameters. The application of 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.

Jankowski, Alan F. (Livermore, CA); Schmid, Anthony P. (Solana Beach, CA)

2000-01-01T23:59:59.000Z

478

Thin film adhesion by nanoindentation-induced superlayers. Final report  

SciTech Connect (OSTI)

This work has analyzed the key variables of indentation tip radius, contact radius, delamination radius, residual stress and superlayer/film/interlayer properties on nanoindentation measurements of adhesion. The goal to connect practical works of adhesion for very thin films to true works of adhesion has been achieved. A review of this work titled ''Interfacial toughness measurements of thin metal films,'' which has been submitted to Acta Materialia, is included.

Gerberich, William W.; Volinsky, A.A.

2001-06-01T23:59:59.000Z

479

Synthesis of thin films and materials utilizing a gaseous catalyst  

DOE Patents [OSTI]

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.

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

2013-10-29T23:59:59.000Z

480

Fabrication and testing of thermoelectric thin film devices  

SciTech Connect (OSTI)

Two thin-film thermoelectric devices are experimentally demonstrated. The relevant thermal loads on the cold junction of these devices are determined. The analytical form of the equation that describes the thermal loading of the device enables one to model the performance based on the independently measured electronic properties of the films forming the devices. This model elucidates which parameters determine device performance, and how they can be used to maximize performance.

Wagner, A.V.; Foreman, R.J.; Summers, L.J.; Barbee, T.W. Jr.; Farmer, J.C. [Lawrence Livermore National Lab., CA (United States). Chemistry and Materials Science Dept.

1996-03-01T23:59:59.000Z

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481

Thin-film aerogel thermal conductivity measurements via 3?  

Science Journals Connector (OSTI)

The limiting constraint in a growing number of nano systems is the inability to thermally tune devices. Silica aerogel is widely accepted as the best solid thermal insulator in existence and offers a promising solution for microelectronic systems needing superior thermal isolation. In this study, thin-film silica aerogel films varying in thickness from 250 to 1280 nm were deposited on SiO2 substrates under a vari