Patent ID: 7964910

Claim:
A field effect transistor comprising: a substrate having a top surface; a channel region in said substrate at said top surface; a trench isolation region comprising: a trench extending into said substrate from said top surface, said trench comprising a sidewall essentially normal to said top surface; and an isolation material filling said trench; and a source/drain region positioned laterally between said channel region and said sidewall of said trench isolation region, said source/drain region comprising: a recess extending into said substrate from said top surface, said recess comprising: an upper edge at said top surface of said substrate; a bottom surface essentially parallel to said top surface of said substrate; a first side surface adjacent to said channel region and extending from said upper edge to said bottom surface, said first side surface having a first profile normal to said top surface of said substrate; and a second side surface opposite said first side surface and extending from said upper edge to said bottom surface, said second side surface having a second profile that is different from said first profile such that said first side surface and said second side surface are not symmetrical, said second profile comprising an angled profile relative to said top surface of said substrate and said sidewall of said trench isolation region such that only said upper edge of said recess at said top surface contacts said trench isolation region and said second side surface comprises only said substrate and not said isolation material; and a semiconductor film filling said recess.