Thin films of gallium arsenide on low-cost substrates. Quarterly technical progress report No. 8 and topical report No. 3, April 2-July 1, 1978

Technical Report · Sat Jul 01 04:00:00 EDT 1978

DOI:https://doi.org/10.2172/5509478· OSTI ID:5509478

Ruth, R. P.; Dapkus, P. D.; Dupuis, R. D.; Johnson, R. E.; Manasevit, H. M.; Moudy, L. A.; Yang, J. J.; Yingling, R. D.

The seventh quarter of work on the contract is summarized. 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 heated in a vertical reactor chamber to temperatures of 725 to 750/sup 0/C, to produce the desired film composition and properties. The technical activities during the quarter were concentrated on (1) a continuing evaluation of various graphite materials as possible substrates for MO-CVD growith of the polycrystalline GaAs solar cells; (2) attempts to improve the quality (especially the grain size) of polycrystalline GaAs films on Mo sheet and Mo/glass substrates by using HCl vapor during the MO-CVD growith process; (3) further studies of the transport properties of polycrystalline GaAs films, wth emphasis on n-type films; (4) continuing investigations of the properties of p-n junctions in polycrystalline GaAs, with emphasis on the formation and properties of p/sup +//n/n/sup +/ deposited structures; and (5) assembling apparatus and establishing a suitable technique for producing TiO/sub 2/ layers for use as AR coatings on GaAs cells. Progress is reported. (WHK)

• Research Organization: Rockwell International Corp., Anaheim, CA (USA)
• OSTI ID: 5509478
• Report Number(s): SAN-1202-78/3
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
36 MATERIALS SCIENCE
360601 -- Other Materials-- Preparation & Manufacture
ANTIREFLECTION COATINGS
ARSENIC COMPOUNDS
ARSENIDES
CARBON
CARRIER DENSITY
CHALCOGENIDES
CHARGE CARRIERS
CHARGE TRANSPORT
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
COATINGS
CRYSTAL STRUCTURE
CRYSTALS
DEPLETION LAYER
DEPOSITION
DESIGN
DIRECT ENERGY CONVERTERS
ELEMENTS
EQUIPMENT
FABRICATION
FILMS
GALLIUM ARSENIDE SOLAR CELLS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
GRAIN BOUNDARIES
GRAIN SIZE
GRAPHITE
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
JUNCTIONS
LAYERS
MICROSTRUCTURE
NONMETALS
OXIDES
OXYGEN COMPOUNDS
P-N JUNCTIONS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PNICTIDES
POLYCRYSTALS
RESEARCH PROGRAMS
SCHOTTKY BARRIER DIODES
SEMICONDUCTOR DEVICES
SEMICONDUCTOR DIODES
SEMICONDUCTOR JUNCTIONS
SIZE
SOLAR CELLS
SOLAR EQUIPMENT
SUBSTRATES
SURFACE COATING
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
VAPOR DEPOSITED COATINGS