Rohm Co., Ltd.

Tomoyasu Sada

Naoki Izumi

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.

Semiconductor device

Lateral double diffused MOSFET device

A semiconductor device according to the present invention includes: a semiconductor layer of a first conductivity type; an annular deep trench penetrating the semiconductor layer in the depth direction to surround an element forming region; a drain region of a second conductivity type formed in a surface layer portion of the semiconductor layer in the element forming region; a drift region of the second conductivity type formed in the surface layer portion of the semiconductor layer to come into contact with the drain region in the element forming region; a body region of the first conductivity type formed in the surface layer portion of the semiconductor layer at an interval from the drift region in the element forming region; a source region of the second conductivity type formed in a surface layer portion of the body region; and a first high-concentration buried region, formed in the semiconductor layer between a portion opposed to the source region in the depth direction and the deep trench, having a higher impurity concentration than that of the semiconductor layer.

Growing community of inventors

Kyoto, Japan

Tomoyasu Sada