Patent ID: 9461139
Filing Date: 2016-10-04
CPC Classification: H01L

Claim Text:
1. A bipolar transistor device, comprising: a substrate including a semiconductor layer overlying an insulating layer; a transistor base comprising a base region in the semiconductor layer doped with a first conductivity type dopant at a first dopant concentration; a transistor emitter comprising an emitter region doped with a second conductivity type dopant and located adjacent one side of the base region; a transistor collector comprising a collector region doped with the second conductivity type dopant and located adjacent an opposite side of the base region; and an extrinsic base comprising an epitaxial semiconductor layer in contact with a top surface of the base region, said epitaxial semiconductor layer doped with the first conductivity type dopant at a second dopant concentration greater than the first dopant concentration, wherein the epitaxial semiconductor layer of the extrinsic base has a thickness of between 3-10 nm.