Patent ID: 7262483

Claim:
A method for manufacturing a semiconductor device having a bipolar transistor, comprising the steps of: forming a collector on a surface of a semiconductor substrate, and forming an insulation film on said semiconductor substrate; forming a conductive film on said insulation film; forming an opening in said insulation film and said conductive film, said opening exposing at least a part of said collector; forming a semiconductor film by non-selective epitaxial growth inside said opening, said semiconductor film being connected to said collector and said conductive film; and forming an emitter on said semiconductor film, wherein, in said step of forming a semiconductor film, a portion in contact with said collector of said semiconductor film is formed of single crystal, a portion in contact with a side surface of said conductive film is formed of polycrystal, and a thickness, in a vertical direction relative to the side surface of said conductive film, of the portion in contact with the side surface of said conductive film is one to two times as thick as a thickness, in a vertical direction relative to said semiconductor substrate, of the portion in contact with said collector.