Patent ID: 8581298
Filing Date: 2013-11-12
Classification: H01L

Abstract:
1. A semiconductor device comprising: an emitter layer of a first conductivity type; a first first-conductivity-type semiconductor layer provided on the emitter layer and having a lower impurity concentration than the emitter layer; a second first-conductivity-type semiconductor layer provided on the first first-conductivity-type semiconductor layer, the second first-conductivity-type semiconductor layer having a higher impurity concentration than the first first-conductivity-type semiconductor layer and having a lower impurity concentration than the emitter layer; a second-conductivity-type semiconductor layer provided on the second first-conductivity-type semiconductor layer; a first main electrode provided in contact with the second-conductivity-type semiconductor layer; a second main electrode provided in contact with the emitter layer; a plurality of gate electrodes having one end portion provided at the second-conductivity-type semiconductor layer side and another end portion provided at the first first-conductivity-type semiconductor layer side; and a gate insulating film provided between the gate electrodes and the second-conductivity-type semiconductor layer, between the gate electrodes and the second first-conductivity-type semiconductor layer, and between the gate electrodes and the first first-conductivity-type semiconductor layer; the second first-conductivity-type semiconductor layer being provided between the second-conductivity-type semiconductor layer and the first first-conductivity-type semiconductor layer, and spacing between the plurality of the gate electrodes being configured so that a depletion layer is pinched off in the second first-conductivity-type semiconductor layer between adjacent ones of the gate electrodes with the first main electrode being short-circuited to the gate electrodes and a reverse voltage being applied between the first main electrode and the second main electrode.