Patent ID: 10062778

Abstract:
A semiconductor device according to the present invention includes: an insulating layer; a semiconductor layer of a first conductive type laminated on the insulating layer; an annular deep trench having a thickness reaching the insulating layer from a top surface of the semiconductor layer; a body region of a second conductive type formed across an entire thickness of the semiconductor layer along a side surface of the deep trench in an element forming region surrounded by the deep trench; a drift region of the first conductive type constituted of a remainder region besides the body region in the element forming region; a source region of the first conductive type formed in a top layer portion of the body region; a drain region of the first conductive type formed in a top layer portion of the drift region; and a first conductive type region formed in the drift region, having a deepest portion reaching a position deeper than the drain region, and having a first conductive type impurity concentration higher than the first conductive type impurity concentration of the semiconductor layer and lower than the first conductive type impurity concentration of the drain region.