Patent ID: 7989845

Claim:
A semiconductor device, comprising: a hetero junction bipolar transistor formed on a first region of a semiconductor substrate; and a field effect transistor formed on a second region of the semiconductor substrate, wherein said hetero junction bipolar transistor includes an emitter layer of a first conductivity type, a base layer of a second conductivity type, a collector layer of the first conductivity type or a non-doped collector layer, and a sub-collector layer of the first conductivity type which are formed sequentially on the first region, said base layer has a band gap smaller than a band gap of said emitter layer, and said field effect transistor includes an electron donor layer including a part of said emitter layer, and a channel layer formed under said electron donor layer, wherein said hetero junction bipolar transistor further includes an emitter contact region of the first conductivity type formed in said first region, an emitter electrode that contacts said emitter contact region, a base electrode that contacts said base layer, and a collector electrode that contacts said sub-collector layer, said base electrode being formed in a region distinct from a region on a line that connects said collector electrode and said emitter electrode in a plane view.