Abstract:
A process for epitaxially depositing germanium on a substrate comprises:- 1) passing a mixture of hydrogen or helium and a germanium halide, halogen or halogen acid into a first reactor containing Ge, and 2) passing the product of the first stage, mixed with hydrogen, into a second reaction chamber containing a germanium substrate. The reactor in step 1 is preferably packed with a bed of germanium at a temperature of 290 DEG - 450 DEG C. and the substrate in step 2 is preferably maintained at 500-920 DEG C. Gaseous doping agents may also be included in the feed mixture to give various kinds of semi-conductor structures.ALSO:A process for epitaxially depositing silicon on a substrate comprises: (1) passing a mixture of hydrogen or helium with a silicon halide, a halogen or a halogen acid into a first reaction chamber containing silicon (preferably a packed bed thereof at 700-980 DEG C.), and (2) passing the product of step 1 mixed with hydrogen into a second reaction chamber containing a silicon substrate (preferably at 1050-1250 DEG C.). Gaseous doping agents may be included in the feed mixture to give various kinds of semiconductor structures.