Patent ID: 9356135
Filing Date: 2016-05-31
CPC Classification: H01L

Claim Text:
1. A semiconductor device having a lateral insulating gate type field effect transistor, the semiconductor device comprising: a semiconductor substrate having one and the other main surfaces being opposed to each other; a lower RESURF region arranged within the semiconductor substrate; a first conductivity type first buried region formed within the semiconductor substrate to contact with the lower RESURF region on a side of the lower RESURF region facing the one main surface; and a second conductivity type upper RESURF region formed within the semiconductor substrate to contact with the first buried region on a side of the first buried region facing the one main surface, wherein the semiconductor substrate has a field oxide formed so as to reach the upper RESURF region on a side of the upper RESURF region facing the one main surface, and includes a second conductivity type body region formed so as to contact with the upper RESURF region on a side of the upper RESURF region facing toward the one main surface and directly adjacent to the field oxide on a different side, and wherein the semiconductor substrate has a gate trench formed directly adjacent to the body region and a surface of the upper RESURF region, and further includes a gate electrode of the insulating gate type field effect transistor formed within the gate trench so as to oppose the body region and the upper RESURF region via a gate insulating film.