Thin films of gallium arsenide on low-cost substrates. Annual report, September 1, 1976-August 31, 1977
Efforts during this year have been directed to (1) the construction of two gallium arsenide deposition systems using the halide process, (2) the preparation of tungsten/graphite and germanium(recrystallized)/tungsten/graphite substrates, (3) the deposition and characterization of gallium arsenide on tungsten/graphite substrates, and the fabrication and characterization of thin film gallium arsenide solar cells, and (4) the deposition and characterization of gallium arsenide films on germanium (recrystallized)/tungsten/graphite substrates and the fabrication of solar cells. Gallium arsenide films have been deposited on W/graphite substrates under a wide range of substrate temperature and reactant composition, and their properties have been evaluated. Films deposited under optimum conditions have an average crystallite size of about 15 ..mu..m and are essentially polycrystalline. Schottky barriers on these films do not exhibit ideal behaviors. MOS type solar cells with an AM1 efficiency (no AR coatings) of up to 3.5% have been produced. Gallium arsenide films deposited on Ge(recrystallized)/W/graphite substrates have considerably larger crystallites with a strong (111) preferred orientation and contains a high concentration of germanium, about 10/sup 17/ cm/sup -3/. Solar cells from these films have poor characteristics due to the high diffusion rate of germanium along grain boundaries.
- Research Organization:
- Southern Methodist Univ., Dallas, TX (USA)
- DOE Contract Number:
- AC03-76SF01284
- OSTI ID:
- 6299187
- Report Number(s):
- DOE/SF/01284-T4
- Country of Publication:
- United States
- Language:
- English
Similar Records
Thin films of gallium arsenide on low-cost substrates. Quarterly project report No. 2, December 1, 1976--February 28, 1977
Thin films of gallium arsenide on low-cost substrates. Quarterly project report No. 1, September 1, 1976--November 30, 1976
Related Subjects
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
ARSENIC COMPOUNDS
ARSENIDES
CARBON
CHEMICAL COATING
CHEMICAL VAPOR DEPOSITION
CRYSTAL STRUCTURE
CRYSTALS
DEPOSITION
DIRECT ENERGY CONVERTERS
ELECTRICAL PROPERTIES
ELECTRON MICROSCOPY
ELEMENTS
EQUIPMENT
FABRICATION
GALLIUM ARSENIDE SOLAR CELLS
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
GERMANIUM
GRAIN SIZE
GRAPHITE
METALS
MICROSCOPY
MICROSTRUCTURE
MOS SOLAR CELLS
NONMETALS
ORIENTATION
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
PNICTIDES
POLYCRYSTALS
REFRACTORY METALS
SCANNING ELECTRON MICROSCOPY
SCHOTTKY BARRIER SOLAR CELLS
SIZE
SOLAR CELLS
SOLAR EQUIPMENT
SPECTRAL RESPONSE
SUBSTRATES
SURFACE COATING
TRANSITION ELEMENTS
TUNGSTEN