Patent ID: 7999312
Filing Date: 2011-08-16
Classification: H01L

Abstract:
1. An insulated gate-type semiconductor device having a body region which is located at an upper surface side within a semiconductor substrate and is a semiconductor of a first conductive type, and a drift region which is in contact with a lower face of the body region and is a semiconductor of a second conductive type, comprising: a trench passing from an upper surface of the semiconductor substrate through the body region; a gate insulating film positioned at a side wall of the trench; a gate electrode located inside the trench facing to the body region through the gate insulating film; a buried diffusion region which is positioned below the gate electrode, is surrounded with the drift region and surrounds a bottom of the trench therewith, and is a semiconductor of the first conductive type; and a low concentration diffusion region which is in juncture with the body region and the buried diffusion region, is lower in concentration than the buried diffusion region, and is a semiconductor of the first conductive type.