Patent ID: 7375410

Claim:
A bipolar transistor comprising: a semiconductor substrate layer; a conductive back electrode located over the semiconductor substrate layer for receiving a bias voltage; an insulating layer located directly over said conductive back electrode; a first semiconductor layer located over said insulating layer, wherein said first semiconductor layer comprises a base which includes a first conductive type dopant and an extrinsic collector which includes a second conductivity type dopant, said extrinsic collector borders said base, and said base is electrically isolated from said conductive back electrode; and an emitter comprising a second semiconductor layer of the second conductivity type dopant located over a portion of said base, wherein said conductive back electrode is biased to form an inversion charge layer at a bottom portion of said base region at an interface between said first semiconductor layer and said insulating layer and said inversion charge layer serves as an intrinsic collector of said transistor.