Patent ID: 7214558

Claim:
A method of manufacturing a semiconductor device including a hetero-junction bipolar transistor (HBT), comprising steps of: (a) preparing a substrate having a main surface and a back surface opposite thereto, the substrate having a first region and a second region; (b) forming a collector layer of the HBT over the main surface in the first region of the substrate; (c) forming a base layer of the HBT over the collector layer in the first region; (d) forming an emitter layer of the HBT over the base layer in the first region; (e) forming a collector electrode over the collector layer in the first region, the collector electrode being electrically connected with the collector layer; (f) forming a base electrode over the base layer in the first region, the base electrode being electrically connected with the base layer; (g) forming, in the same step, an emitter electrode over the emitter layer in the first region and a backside via electrode in the second region, the emitter electrode being electrically connected with the emitter layer; (h) forming a via hole from the back surface of the substrate to the backside via electrode in the second region; (i) forming a back electrode on the back surface of the substrate and inside the via hole, the back electrode being electrically connected with the backside via electrode; and (j) forming a collector extraction interconnect, a base extraction interconnect, an emitter extraction interconnect and an interconnect for the backside via electrode, each electrically connected with the collector layer, base layer, emitter layer and backside via electrode, respectively.