Patent ID: 8872257

Claim:
A semiconductor device comprising: a first region; a second region; and a third region provided between the first region and the second region, the first region including: a first semiconductor layer of a first conductivity type; a first semiconductor region of a second conductivity type provided on the first semiconductor layer; a second semiconductor region of the first conductivity type provided on the first semiconductor region; a third semiconductor region of the second conductivity type being in contact with the first semiconductor region, and the third semiconductor region having higher impurity concentration than the first semiconductor region; a first electrode electrically connected to the second semiconductor region and the third semiconductor region; a second electrode electrically connected to the first semiconductor layer; an insulating film extending from a surface of the first semiconductor region into the first semiconductor layer; a third electrode in contact with the first semiconductor region via the insulating film; a fourth electrode in contact with the first semiconductor layer and the third electrode via the insulating film, the second region including a pad electrode electrically connected to the third electrode above the first semiconductor layer, and the third region including: the first semiconductor layer; the first semiconductor region provided on the first semiconductor layer; the third semiconductor region in contact with the first semiconductor region; the first electrode electrically connected to the third semiconductor region; the second electrode electrically connected to the first semiconductor layer; and a first insulating layer extending from a position of the third semiconductor region to a position of the first semiconductor layer.