Patent ID: 8710542

Claim:
A semiconductor device comprising: a base layer; a second conductivity type semiconductor layer provided on a first side of the base layer; a first insulating film provided on an inner wall of a plurality of first trenches that each extend from a first surface of the second conductivity type semiconductor layer that is substantially parallel to the base layer toward the base layer, but do not reach the base layer; and a first electrode provided in each first trench on the first insulating film and electrically contacting the second conductivity type semiconductor layer at the first surface and at a first side surface of the second conductivity type semiconductor layer that intersects the first surface, the second conductivity type semiconductor layer including: a first second conductivity type region provided between the first trenches; and a second second conductivity type region provided between the first second conductivity type region and the base layer and between a bottom part of each first trench and the base layer, the second second conductivity type region having a quantity of second conductivity type impurities that is less than a quantity of second conductivity type impurities in the first second conductivity type region.