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
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)
- DOE Contract Number:
- EY-76-C-03-1202
- OSTI ID:
- 5324249
- Report Number(s):
- SAN-1202-78/2
- Country of Publication:
- United States
- Language:
- English
Similar Records
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
Thin films of gallium arsenide on low-cost substrates. Final report, July 5, 1976--July 2, 1977
Related Subjects
36 MATERIALS SCIENCE
GALLIUM ARSENIDE SOLAR CELLS
FABRICATION
GALLIUM ARSENIDES
CHEMICAL VAPOR DEPOSITION
ALUMINIUM ALLOYS
COST
CRYSTAL DOPING
ENERGY GAP
FILMS
GLASS
GRAIN BOUNDARIES
GRAIN SIZE
GRAPHITE
MOLYBDENUM
P-N JUNCTIONS
PRODUCTION
SHEETS
SUBSTRATES
THICKNESS
ALLOYS
ARSENIC COMPOUNDS
ARSENIDES
CARBON
CHEMICAL COATING
CRYSTAL STRUCTURE
DEPOSITION
DIMENSIONS
DIRECT ENERGY CONVERTERS
ELEMENTS
EQUIPMENT
GALLIUM COMPOUNDS
JUNCTIONS
METALS
MICROSTRUCTURE
NONMETALS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PNICTIDES
REFRACTORY METALS
SEMICONDUCTOR JUNCTIONS
SIZE
SOLAR CELLS
SOLAR EQUIPMENT
SURFACE COATING
TRANSITION ELEMENTS
140501* - Solar Energy Conversion- Photovoltaic Conversion
360601 - Other Materials- Preparation & Manufacture