Heteroepitaxial deposition of gap on silicon substrates

摘要

A crack free layer of GaP is epitaxially deposited on a silicon phosphide surface of a silicon substrate having an (III) orientation. The silicon substrate is prebaked on a carbide coated susceptor with palladium diffused hydrogen at about 1200 DEG C and pretreated with phosphine at about 1140 DEG C to form the silicon phosphide surface. The temperature is lowered to 800 DEG -900 DEG C in the presence of phosphine and trimethyl gallium is introduced at a ratio of 1 to 10 with the phosphine. Cracks in the gallium phosphide are prevented by roughing the bottom non-phosphide surface of the silicon substrate such that the roughed surface is under compressive stress and induces tensile stress on the phosphided surface to reduce the compressive stress reduced by gallium phosphide layer when the substrate is annealed at about 1200 DEG C.