High breakdown voltage semiconductor device

摘要

A semiconductor device which comprises a substrate (1); an insulating layer (2) formed on said substrate (1); a high resistance semiconductor layer (4) formed on said insulating layer (2); a dielectric isolation region (3) formed in said high resistance semiconductor layer (4); an element region formed in said high resistance semiconductor layer (4) isolated by said dielectric isolation region (3) in a lateral direction; a first low resistance region (6) of a first conductivity type formed in a surface portion of said element region; a second low resistance region (7) of a second conductivity type formed in said element region between said first low resistance region (6) and said dielectric isolation region (3) to be separated from said first low resistance region (6); and a third low resistance region (27) of a first conductivity type formed contiguous with the isolation region (3). <IMAGE>