Patent ID: 7170113
Filing Date: 2007-01-30
Classification: H01L

Abstract:
1. A semiconductor device comprising: a collector layer of first conductive type formed on a semiconductor substrate; a graft base layer of second conductive type formed in a surface region of the collector layer; a first base leading-out region of second conductive type formed on the graft base layer; a second base leading-out region of second conductive type formed on an upper surface and a side surface of the first base leading-out region; a base layer of second conductive type formed on the collector layer; an emitter layer of first conductive type formed in a surface region of the base layer; and an emitter leading-out region formed on the emitter layer, wherein the base layer is also formed on the second base leading-out region, and at least part of an impurity concentration profile of the second base leading-out region is smaller than an impurity concentration of the first base leading-out region.