Patent ID: 9224858
Filing Date: 2015-12-29
Classification: H01L

Abstract:
1. A field effect transistor comprising: a semiconductor substrate having a first type conductivity; an etch stop pad on said semiconductor substrate; a semiconductor layer on said semiconductor substrate positioned laterally immediately adjacent to said etch stop pad and further extending over said etch stop pad; a first well region extending from a top surface of said semiconductor layer into said semiconductor substrate such that said etch stop pad is contained within said first well region, said first well region having a second type conductivity different from said first type conductivity; a second well region within said first well region at said top surface of said semiconductor layer and aligned above said etch stop pad, said second well region having said first type conductivity; a source region within said second well region at said top surface of said semiconductor layer; a drain region within said first well region at said top surface of said semiconductor layer and separated from said second well region, said source region and said drain region each having said second type conductivity; and, a buried isolation region within said first well region aligned below said etch stop pad.