Patent ID: 9048278
Filing Date: 2015-06-02
Classification: H01L

Abstract:
1. A semiconductor device, comprising: a first conductivity type first semiconductor layer; a second conductivity type emitter semiconductor layer disposed on the first semiconductor layer; a first conductivity type base semiconductor layer selectively disposed on the emitter semiconductor layer; a second conductivity type collector semiconductor layer selectively disposed on the base semiconductor layer; a insulating film disposed on the collector semiconductor layer; a pad electrode disposed on the insulating film, electrically connected via a plurality of contact holes formed in the insulating film to the collector semiconductor layer; and a metal electrode electrically connected to the first semiconductor layer, emitter semiconductor layer, and base semiconductor layer, wherein the width of the base semiconductor layer sandwiched between the emitter semiconductor layer and collector semiconductor layer is greater than the width of a depletion layer spreading toward the first semiconductor layer in the base semiconductor layer at the avalanche voltage of a diode formed of the collector semiconductor layer and base semiconductor layer, and a transistor formed of the collector semiconductor layer, base semiconductor layer, and emitter semiconductor layer becomes conductive at a voltage higher than the avalanche voltage of the diode.