Patent ID: 7626229
Filing Date: 2009-12-01
Classification: H01L

Abstract:
1. A semiconductor device, comprising: a semiconductor substrate; a first conductivity type drain region provided in a lower part of said semiconductor substrate; a second conductivity type substrate region provided on said drain region in said semiconductor substrate; a first conductivity type source region provided on said substrate region in said semiconductor substrate; a trench formed in said semiconductor substrate and reaching said drain region; a gate insulating film provided at least on a side wall of said trench; a gate electrode provided on said gate insulating film in said trench; a second conductivity type pocket region provided between said substrate region and said source region and being in contact with said source region; an insulating film formed in said trench to cover said gate electrode and having an upper end located lower than an upper surface of said semiconductor substrate; a source electrode provided above said source region; and a second conductivity type high concentration substrate region formed so as to be adjacent to said source region on said substrate region in said semiconductor substrate and having an impurity concentration higher than that of said substrate region, wherein said gate insulating film is in contact with said substrate region and said pocket region at said side wall of said trench, and said source electrode is in contact with an upper surface of said source region, and in contact with a portion of a side surface of said source region which is located above said upper end of said insulating film in said trench.