Patent ID: 8866264

Claim:
A semiconductor device comprising: a semiconductor substrate of a first conductivity type; a first semiconductor layer of a second conductivity type formed on a first face of the semiconductor substrate, the second conductivity type being of an opposite conductivity of the first conductivity type; a second semiconductor layer of the first conductivity type formed in the first semiconductor layer; a first insulation film formed over the first and second semiconductor layers on the first face of the semiconductor substrate, first insulation film having a first aperture forming an opening to the first semiconductor layer and a second aperture forming an opening to the second semiconductor layer; a second insulation film formed over the first insulation film, the second insulation film having at least one third aperture located between the first aperture and the second aperture; a first main electrode formed on a second face of the semiconductor substrate opposite to the first face; a second main electrode formed in the first aperture; and a third main electrode formed in the second aperture and the at least one third aperture.