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

Technical Report · Sat Apr 01 04:00:00 EST 1978

DOI:https://doi.org/10.2172/5324249· OSTI ID:5324249

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

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 substrate materials used for experimental studies during the quarter included several grades of graphite (from two different manufacturers), commercial-grade Al alloy sheet, large-grained annealed Mo sheet, sputtered Mo films on Corning Code 0317 glass, uncoated 0317 glass, large-grained polycrystalline alumina (Coors Vistal 5), and large-grained bulk polycrystalline GaAs. Results indicted graphite to be a suitable substrate for GaAs film growth by MO-CVD, although some adherence problems were uncountered with improperly prepared graphite surfaces. No major differences were observed for GaAs growth on the various graphites; films approx. 10 ..mu..m thick exhibited apparent grain sizes (indicated by dimensions of surface features) in the 2 to 5 ..mu..m range. Annealed Mo sheet substrate having relatively large grain structure did not appear to produce correspondingly large grains in deposited polycrystalline GaAs films. Results are reported in detail. (WHK)

• Research Organization: Rockwell International Corp., Anaheim, CA (USA)
• OSTI ID: 5324249
• Report Number(s): SAN-1202-78/2
• 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
ALLOYS
ALUMINIUM ALLOYS
ARSENIC COMPOUNDS
ARSENIDES
CARBON
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
COST
CRYSTAL DOPING
CRYSTAL STRUCTURE
DEPOSITION
DIMENSIONS
DIRECT ENERGY CONVERTERS
ELEMENTS
ENERGY GAP
EQUIPMENT
FABRICATION
FILMS
GALLIUM ARSENIDE SOLAR CELLS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
GLASS
GRAIN BOUNDARIES
GRAIN SIZE
GRAPHITE
JUNCTIONS
METALS
MICROSTRUCTURE
MOLYBDENUM
NONMETALS
P-N JUNCTIONS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PNICTIDES
PRODUCTION
REFRACTORY METALS
SEMICONDUCTOR JUNCTIONS
SHEETS
SIZE
SOLAR CELLS
SOLAR EQUIPMENT
SUBSTRATES
SURFACE COATING
THICKNESS
TRANSITION ELEMENTS