Patent ID: 7115965

Claim:
A bipolar transistor comprising: a conductive back electrode for receiving a bias voltage; a second buried insulating layer located over said conductive back electrode having a second thickness; a first buried insulating layer located adjacent to said second buried insulating layer and said conductive back electrode, said first buried insulating layer having a first thickness that is greater than the second thickness; a first semiconductor layer located predominately over said second buried insulating layer, said first semiconductor layer including a first conductive type dopant, wherein said conductive back electrode is biased to form an accumulation layer in said first semiconductor layer at an interface between said first semiconductor layer and said second buried insulating layer; a base located atop at least said first semiconductor layer, said base comprising a second semiconductor layer having a second conductivity type dopant that differs from the first conductivity type dopant; and an emitter comprising a third semiconductor layer of the first conductivity type dopant located over a portion of said base.