Patent ID: 9490247
Filing Date: 2016-11-08
CPC Classification: H01L

Claim Text:
1. A semiconductor device comprising: a first semiconductor layer of a first conductivity type; a second semiconductor layer of a second conductivity type formed on one main surface side of the first semiconductor layer, the second conductivity type being different from the first conductivity type; a first transistor formed on the other main surface side of the first semiconductor layer and including a first gate electrode; a second transistor formed on the other main surface side of the first semiconductor layer and including a second gate electrode electrically connected with the first gate electrode; an emitter electrode electrically connected with the first transistor and the second transistor; a collector electrode electrically connected with the second semiconductor layer; and a first semiconductor region of the second conductivity type formed in contact with the second transistor within the first semiconductor layer, wherein when the first transistor and the second transistor are in an on-state, a current composed of charges of a first polarity and charges of a second polarity opposite to the first polarity flows from the collector electrode through the first transistor to the emitter electrode but does not flow through the second transistor, and when the first transistor and the second transistor are switched from the on-state to the off-state, a current composed of charges of the second polarity flows from the first semiconductor layer through the first transistor to the emitter electrode and a current composed of charges of the second polarity flows from the first semiconductor layer through the first semiconductor region and the second transistor to the emitter electrode.