METHOD OF FORMING EPITAXIAL FILM HAVING DEFECT-FREE REGION ON SUBSTRATE, AND SUBSTRATE WITH EPITAXIAL FILM HAVING DEFECT-FREE REGION

摘要

PROBLEM TO BE SOLVED: To solve such a problem that when forming an epitaxial film of a harder material than a relatively soft substrate, e.g., a metal substrate, on the substrate, a stress due to lattice matching therebetween causes a defect on the substrate side, and it appears as the defect of the epitaxial film.SOLUTION: After forming an extremely shallow trench on the substrate surface, epitaxial growth is performed on that surface. Since a stress due to lattice matching is released in the trench and is not propagated nor stored over the entire substrate surface, when an arbitrary region on the substrate surface is isolated from the stress remotely by the trench, the defect is never formed in that region.