Patent ID: 9741836
Date: 2017-08-22
CPC Classifications: H01L,H03K

Claim:
1. A semiconductor device, comprising: a first semiconductor layer of a first conductivity type; a second semiconductor layer of a second conductivity type provided on the first semiconductor layer; a third semiconductor layer of the first conductivity type provided on the second semiconductor layer, a carrier concentration of the third semiconductor layer being higher than a carrier concentration of the first semiconductor layer; a fourth semiconductor layer of the second conductivity type provided on the second semiconductor layer, a carrier concentration of the fourth semiconductor layer being higher than a carrier concentration of the second semiconductor layer; a first electrode connected to the second semiconductor layer and the fourth semiconductor layer; a second electrode facing the second semiconductor layer with an insulating film interposed; a fifth semiconductor layer of the second conductivity type provided under the first semiconductor layer; a sixth semiconductor layer of the first conductivity type provided under the fifth semiconductor layer, a carrier concentration of the sixth semiconductor layer being higher than the carrier concentration of the first semiconductor layer; a seventh semiconductor layer of the second conductivity type provided under the fifth semiconductor layer, a carrier concentration of the seventh semiconductor layer being higher than a carrier concentration of the fifth semiconductor layer; a third electrode connected to the fifth semiconductor layer and the seventh semiconductor layer; and a fourth electrode facing the fifth semiconductor layer with an insulating film interposed.