Patent ID: 9691886
Date: 2017-06-27
CPC Classifications: H01L

Claim:
1. A semiconductor structure comprising: an emitter and a collector spaced apart from each other and located on an insulator layer, wherein the emitter and the collector include a semiconductor material and have a doping of a first conductivity type; an intrinsic base disposed in between the emitter and the collector and on the insulator layer, wherein the intrinsic base includes a semiconductor material and has a doping of a second conductivity type which is opposite to the first conductivity type; and an extrinsic base disposed on a top surface of the intrinsic base, wherein a bottom surface of the extrinsic base has an epitaxial relationship with the top surface of the intrinsic base, wherein the intrinsic base contacts the emitter, the collector and the extrinsic base and wherein the intrinsic base has an energy band gap less than an energy band gap of the emitter and an energy band gap of the collector, wherein a top surface of the intrinsic base is located above a top surface of the emitter and a top surface of the collector.