DEVICE QUALITY POLYCRYSTALLINE GALLIUM-ARSENIDE ON GERMANIUM-MOLYBDENUM SUBSTRATES

This paper describes the growth of polycrystalline films of gallium arsenide on molybdenum substrates with an intermediate layer of germanium. The gallium arsenide layer is grown by the reaction of trimethylgallium and arsine in a cold-wall reactor system. Germanium layers are formed by vacuum evaporation, as well as by the pyrolysis of germane gas. Techniques are described for minimizing massive autodoping effects which are commonly observed in the heteroepitaxy of these semiconductors. Doping concentrations in the range of (7-13) × 1015/cma are obtained for the gallium arsenide film. Schottky diodes, fabricated in this material, exhibit avalanche breakdown in the range of 30-35V. © 1979, The Electrochemical Society, Inc. All rights reserved.