Patent ID: 9741797
Date: 2017-08-22
CPC Classifications: H01L

Claim:
1. An insulated gate silicon carbide semiconductor device, comprising: a silicon carbide substrate of 4H type with a {0001} plane having an off-angle of more than 0° as a main surface; a drift layer of a first conductivity type provided on said silicon carbide substrate; a first base region of a second conductivity type located on a surface side of said drift layer; a source region of the first conductivity type located in said first base region; a trench that penetrates said first base region and said source region and has a trench side wall formed of a plurality of surfaces; a gate insulating film formed on said trench side wall in said trench; a gate electrode buried in said trench through said gate insulating film; a protective diffusion layer of the second conductivity type provided in said drift layer while being in contact with a bottom of said trench; and a second base region of the second conductivity type provided in said drift layer while being in contact with part of said protective diffusion layer, part of said first base region, and at least part of only one surface of said plurality of surfaces of said trench side wall, wherein said one surface of said trench side wall in contact with said second base region is a surface having a trench off-angle of more than 0° in a <0001>direction with respect to a plane parallel to the <0001>direction, and said first base region is in contact with said trench.