Patent ID: 6627499
Filing Date: 2003-09-30
Classification: H01L

Abstract:
A method of manufacturing a semiconductor device, comprising the steps of:forming a semiconductor layer of a first conductivity type on one main surface of a semiconductor substrate; forming a base region of a second conductivity type in a surface region of a drain region of the first conductivity type formed in the semiconductor layer of the first conductivity type; forming a source region of the first conductivity type in a surface region of the base region; forming a trench extending from the surface of the base region through the base region to reach an inner region of the drain region; forming an impurity diffusion region of the second conductivity type having an impurity concentration lower than that in the base region in the periphery of the side wall of that portion of the trench which is positioned within the drain region; burying a conductive layer and/or an insulating layer within the trench; forming a gate insulating film in a manner to cover a part of the surfaces of the drain region, the base region and the source region; and forming a gate electrode on the gate insulating film.