Thin-phase epitaxy for good semiconductor metal ohmic contacts

Ohmic contacts of superior quality are produced by treating the normal alloying process as an epitaxy process, where Ga and As are supplied separately by evaporation together with the normal contact metals and by overpressure, respectively. New device fabrication methods based on this new scheme are the production of shallow p-n junctions, shallow heterojunctions, thin ternary semiconductor layers with different bandgaps from that of the bulk, and multiple structures. By using photoresist, complete regrowth patterns as used for IC's should be possible. The types of devices where these developments should be of interest are solar cells, light-emitting IC patterns, even with different light colors on one chip, Gunn devices, BARITT's, MESFET's, Schottky CCD's, heterojunction bipolar transistors, etc.