Patent ID: 6638806
Filing Date: 2003-10-28
Classification: H01L

Abstract:
A method of fabricating a semiconductor device having a bipolar transistor and a field-effect transistor formed on a semiconductor substrate, comprising steps of:successively forming a first oxide film for defining a gate oxide film and a first conductor film for defining a lower portion of a gate electrode on said semiconductor substrate formed with a collector region; selectively etching said first conductor film and said first oxide film for exposing a surface portion of said semiconductor substrate located on a region for forming said bipolar transistor; forming a second conductor film for defining an external base electrode and an upper portion of said gate electrode on said semiconductor substrate to come into contact with said exposed surface portion and cover a region for forming said field-effect transistor and said collector region; forming a second oxide film on said semiconductor substrate to cover said second conductor film; selectively etching said second conductor film and said second oxide film for exposing a surface portion of said semiconductor substrate thereby opening an emitter region; forming a third conductor film for defining an emitter electrode on said second oxide film to come into contact with said emitter region; patterning said third conductor film for forming said emitter electrode on said semiconductor substrate; and patterning said second oxide film, said second conductor film and said first conductor film for simultaneously forming said external base electrode and said gate electrode.