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Electrochemical photovoltaic cells. Project 65021 quarterly technical progress report, October 15, 1979-January 15, 1980

Description: During the third quarter of this program, liquid junction devices based upon the semiconductors MoSe/sub 2/, MoS/sub 2/, GaAs, and CdSe have been evaluated. Lifetime testing of MoSe/sub 2/ and MoS/sub 2/ materials in acidic halogen electrolytes at constant current densities of 5 mA/cm/sup 2/ have shown excellent stability to date. For MoSe/sub 2/ single crystals in the electrolyte 1M HBr + 1M Br/sub 2/, short-circuit currents of 63 mA/cm/sup 2/ were achieved with a power conversion efficiency o… more
Date: March 1, 1980
Creator: Ang, P.G.P.; Remick, R.J. & Sammells, A.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preliminary measurements of gamma ray effects on characteristics of broad-band GaAs field-effect transistor preamplifiers

Description: The effect of gamma radiation on electrical characteristics of cryogenically cooled broad-band low-noise microwave preamplifiers has been preliminarily evaluated. The change in the gain and noise figure of a 1-2 GHz preamplifier using GaAs microwave transistors was determined at gamma doses between 10/sup 5/ rad to 5 /times/ 10/sup 8/ rad. The gain and noise figure was measured at ambient temperatures of 300 K and 80 K. 8 refs., 2 figs.
Date: January 1, 1985
Creator: Jackson, H.G.; Shimizu, T.T. & Leskovar, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Phased-array antenna control by a monolithic photonic integrated circuit, COMPASS

Description: Phased-array antenna systems are well known for rapid beam steering and their ability to bring high power to the target. Such systems are also quite complex and heavy, which have limited their usefulness. The issues of weight, size, power use, and complexity have been addressed through a system named COMPASS (Coherent Optical Monolithic Phased Array Steering System). All phased-array antenna systems need: (1) small size; (2) low power use; (3) high-speed beam steering; and (4) digitally-control… more
Date: January 1, 1991
Creator: Kravitz, S. H.; Hietala, V. M.; Vawter, G. A. & Meyer, W. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vertical bridgman and gradient freeze growth of III-V compound semiconductors

Description: Major improvements in the structural and electrical perfection of single crystals of III-V compound semiconductors have been achieved by using new vertical Bridgman-type and vertical gradient freeze techniques. A general review of experimental set-ups used for growth of large diameter crystals of GaP, InP and GaAs is presented. Crystal properties and characteristic features are discussed to illustrate advantages and disadvantages of the vertical Bridgman-type growth techniques. 22 refs., 5 figs. more
Date: July 1, 1990
Creator: Bourret, E.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Advanced high efficiency concentrator cells

Description: This report describes research to develop the technology needed to demonstrate a monolithic, multijunction, two-terminal, concentrator solar cell with a terrestrial power conversion efficiency greater than 35%. Under three previous subcontracts, Varian developed many of the aspects of a technology needed to fabricate very high efficiency concentrator cells. The current project was aimed at exploiting the new understanding of high efficiency solar cells. Key results covered in this report are as… more
Date: June 1, 1992
Creator: Gale, R. (Varian Associates, Inc., Palo Alto, CA (United States). Varian Research Center)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Plasma Separation Process: Betacell (BCELL) code: User's manual. [Bipolar barrier junction]

Description: The emergence of clearly defined applications for (small or large) amounts of long-life and reliable power sources has given the design and production of betavoltaic systems a new life. Moreover, because of the availability of the plasma separation program, (PSP) at TRW, it is now possible to separate the most desirable radioisotopes for betacell power generating devices. A computer code, named BCELL, has been developed to model the betavoltaic concept by utilizing the available up-to-date sour… more
Date: November 13, 1987
Creator: Taherzadeh, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The polarized electron gun for the SLC

Description: A new polarized electron gun for use on the SLC at SLAC has been built and tested. It is a diode gun with a laser driven GaAs photocathode. It is designed to provide short (2ns) pulses of 10 A at 160 kV at 120 Hz. The design features of the gun and results from a testing program on a new and dedicated beam line are presented. Early results from operation on the SLC will also be shown.
Date: March 1, 1992
Creator: Schultz, D. C.; Clendenin, J.; Frisch, J.; Hoyt, E.; Klaisner, L.; Woods, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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(Defect studies in III-V thin film semiconductors)

Description: Our primary research objective in 90/91 has been to continue studying misfit dislocation confinement by patterning substrates into mesas before the epitaxial growth of strained layers. This report presents progress for many of the areas of our research. (JL)
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thin films of gallium arsenide on low-cost substrates. Quarterly technical progress report No. 6 and topical report No. 2, January 1, 1978-April 1, 1978

Description: The metalorganic chemical vapor deposition (MO-CVD) technique has been applied to the growth of thin films of GaAs and GaAlAs on inexpensive polycrystalline or amorphous substrate materials (primarily glasses and metals) for use in fabrication of large-area low-cost photovoltaic device structures. Trimethylgallium (TMG), arsine (AsH/sub 3/), and trimethylaluminum (TMAl) are mixed in appropriate concentrations at room temperature in the gaseous state and pyrolyzed at the substrate, which is heat… more
Date: April 1, 1978
Creator: Ruth, R. P.; Dapkus, P. D.; Dupuis, R. D.; Campbell, A. G.; Johnson, R. E.; Manasevit, H. M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microscopic determination of stress distribution in GaAs grown at low temperature on GaAs (100)

Description: A microscopic strain distribution across commensurate interfaces between GaAs layers grown on semi-insulating GaAs substrates was observed by means of convergent beam electron diffraction (CBED) and large angle convergent beam methods (LACBED). Strain relaxation at a specific distance from the interface was observed in these layers without formation of misfit dislocations. It was proposed that specific point defects distributed close to the interface can explain the asymmetric broadening of hig… more
Date: January 1991
Creator: Liliental-Weber, Z.; Tanaka, M.; Ishikawa, A. & Teriauchi, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Novel concepts in electrochemical solar cells. First quarterly progress report, May 15-July 15, 1979. [Molten salt electrolytes]

Description: Emphasis has been directed toward the development and evaluation of an efficient, operational photoelectrochemical cell (PEC) system involving (i) molten salt (and/or highly concentrated, inorganic, non-aqueous) electrolytes, and (ii) the promising semiconductor electrode materials such as CuTnS/sub 2/, CuInSe/sub 2/, MoS/sub 2/, MoSe/sup 2/ etc. As a direct consequence, the stages of the work program that are most critical at this time are the electrode fabrication and characterization and the… more
Date: January 1, 1979
Creator: DuBow, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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One Dimensional Polaron Effects and Current Inhomogeneities in Sequential Phonon Emission

Description: We have constructed a physical model to explain the tunneling current oscillations reported by Hickmott et al., for GaAs/AlGaAs heterostructures in high magnetic fields. We propose that the periodic structure observed is due to space charge which builds up in the undepleted layer when electrons enter it with energy just below the phonon emission threshold. Such electrons interact with the lattice to form polarons whose energy is pinned to the phonon energy, and thus has a very small group veloc… more
Date: July 1985
Creator: Hellman, E. S.; Harris, J. S.; Hanna, C. & Laughlin, R. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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US Photovoltaic Patents, 1988--1990

Description: This document contains US patents on terrestrial photovoltaic (PV) power applications, including systems, components, and materials, as well as manufacturing and support functions. The patent entries in this document were issued from 1988 through 1990. The entries were located by searching USPA, the data base of the US Patent Office. The final search retrieved all patents under the class Batteries, Thermoelectric and Photoelectric'' and the subclasses Photoelectric,'' Testing,'' and Application… more
Date: December 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Novel Concepts in Electrochemical Solar Cells. Third Quarterly Progress Report, November 15, 1979-January 15, 1980. [Molten Salt Electrolytes]

Description: Efforts have been primarily directed toward evaluation of the room temperature molten salt electrolyte in terms of its overall performance for photovoltaic cells. Mass transport processes may prove to be the rate-limiting factor for such electrolytes, unless the concentration of the photo-active redox component can be increased and the solvent viscosity reduced. Acid-base surface chemistry of n-GaAs as occurs in aqueous systems, has been found present and its consequences will be further explor… more
Date: January 1, 1980
Creator: DuBow, J.; Job, R. & Krishnan, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Advanced photovoltaic concentrator cells. Quarterly technical progress report No. 2, 1 December 1979-29 February 1980

Description: This report describes second quarter activities for a project aimed at demonstrating the technical feasibility of advanced high efficiency concentrator solar converters. The goal of the program is to achieve 30% conversion efficiency with a converter operating at 30/sup 0/C under 500 to 1000 SUN AM2 illumination and 25% conversion efficiency with a converter operating at 150/sup 0/C under 500 to 1000 SUN AM2 illumination. The approach is to fabricate two cell, non-lattice matched, monolithic st… more
Date: January 1, 1980
Creator: Zehr, S. W.; Yang, H. T.; Yang, J. J. & Harris, J. S. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of photoelectrochemical cells based on compound semiconductors and nonaqueous electrolytes. Semiannual report, May 1, 1981-October 31, 1981

Description: A reproducible procedure for chemical bath deposition (CBD) of CdSe has been documented in detail, allowing a consistent production of photoelectrode yielding 5.5 to 6.5% conversion efficiency in alkaline polysulfide electrolyte (employing a tungsten halogen lamp/KG-2 filter solar simulated light source). The CBD films of n-CdSe on Ti have achieved an efficiency of approx. 10% under both solar simulated and real sunlight conditions using an Fe(CN)/sub 6//sup -3///sup -4/ electrolyte at pH 13. F… more
Date: March 1, 1982
Creator: Rauh, R. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optical pumping of hot phonons in GaAs

Description: Optical pumping of hot LO phonons in GaAs has been studied as a function of the excitation photon frequency. The experimental results are in good agreement with a model calculation which includes both inter- and intra-valley electron-phonon scatterings. The GAMMA-L and GAMMA-X intervalley electron-phonon interactions in GaAs have been estimated.
Date: June 30, 1982
Creator: Collins, C.L. & Yu, P.Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Photovoltaic Subcontract Program, FY 1991

Description: This report summarizes the fiscal year (FY) 1991 (October 1, 1990, through September 30, 1991) progress of the subcontracted photovoltaic (PV) research and development (R D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL) -- formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the… more
Date: March 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Polyacetylene, (CH)/sub x/, as an emerging material for solar cell applications. Second quarterly technical progress report, July-September 1979

Description: As of the starting date of this contract, a variety of rectifying junctions had been fabricated using doped and undoped (CH)/sub x/. Schottky diodes formed between metallic AsF/sub 5/-doped (CH)/sub x/ and n-type semiconductors indicate high (CH(AsF/sub 5/)/sub y/)/sub x/ electronegativity. The p-type character of undoped trans-(CH)/sub x/ was confirmed by Schottky barrier formation with low work function metals. An undoped p-(CH)/sub x/:n--ZnS heterojunction solar cell has been demonstrated wi… more
Date: January 1, 1979
Creator: Heeger, A.J. & MacDiarmid, A.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Feasibility investigation and design study of optical well logging methods for high temperature geothermal wells

Description: The objective of this project was exploration of a novel approach to high temperature well logging, based on a system of optical transducers and an optical transmission line both theoretically capable of operation to at least 600/sup 0/C. The scope of the work involved the accomplishment of ten specific tasks. These had as their objective the determination of feasibility, and identification of major problem areas, in the implementation of continuous temperature logging of geothermal wells using… more
Date: March 1, 1978
Creator: Swanson, R. K.; Anderson, R. E.; Ash, J. I.; Beissner, R. E. & Smith, V. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of polycrystal GaAs solar cells. Quarterly technical progress report No. 2 for May 1-July 31, 1979

Description: Investigation of grain boundaries in GaAs, growth of small-grained GaAs, and solar cell fabrication on small-grained material continued this quarter. Some highlights were the fabrication of MS cells of small-grained GaAs grown on Mo, the fabrication of MIS cells using spin-on oxides, and the determination of interface state density at a high-resistance grain boundary. Initial measurements show that series resistance and shunt leakage seriously degrade the performance of cells made from small-gr… more
Date: September 1, 1979
Creator: Miller, D. L.; Cohen, M. J.; Harris, Jr., J. S.; Ballantyne, J.; Hoyte, A. & Stefanakos, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electronics Engineering Research. Final report, FY 1979

Description: Accomplishments in Electronics Engineering Research (EER) during FY79 spanned a broad range of technologies, from high-speed microelectronics to digital image enhancement; from underground probing with electromagnetic waves to detecting neutrons with a small solid-state device; and from computer systems to aid engineers, to software tools to aid programmers. This report describes the overall EER program and its objectives, summarizes progress made in FY79, and outlines plans for FY80.
Date: January 1, 1980
Creator: Weissenberger, S. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photogenerated carrier-induced reactions on uhv semiconductor surfaces

Description: The objective for this experimental work was to examine the reaction mechanisms, half-collision dynamics, and other optically induced chemical effects, that are operable on a well characterized single-crystal semiconductor surface. Of particular interest were reactions induced by charge transfer from the semiconductor surface including hot carrier and thermalized carrier processes. The primary technique to measure the desorbed fragment translational energies was time-of-flight mass-spectroscopy… more
Date: May 28, 1992
Creator: Osgood, R.M. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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