Patent ID: 8377785

Claim:
A method of forming a field effect transistor comprising: providing a substrate having a top surface; forming a gate on said top surface above a designated channel region in said substrate; forming source/drain regions in said substrate adjacent said channel region, wherein each of said source/drain regions comprises: forming a recess in said substrate using multiple etch processes such that said recess comprises: an upper edge at said top surface of said substrate; a bottom surface approximately parallel to said top surface of said substrate; a first side adjacent to said channel region, extending from said upper edge at said top surface of said substrate to said bottom surface and having a first profile normal to said top surface of said substrate; and a second side opposite said first side, extending from said upper edge at said top surface of said substrate to said bottom surface and having a second profile different from said first profile said second profile being an angled profile relative to said top surface of said substrate, said multiple etch processes comprising a crystallographic etch process and at least one additional etch process; and filling said recess with a semiconductor film.