Patent ID: 7838374

Claim:
A method of manufacturing a bipolar transistor on a semiconductor substrate comprising the steps of: forming on the semiconductor substrate a first, a second and a third layer a first, second and third semiconductor material respectively, all of a first conductivity type; transforming a first portion of the second layer into a buried isolation region comprising a first electrically insulating material; forming a first semiconductor region of the first conductivity type, comprising a collector region or an emitter region, from a second portion of the second layer adjoining the buried isolation region and a portion of the first layer adjoining the second portion of the second layer; forming a base region on the buried isolation region and on the first semiconductor region by transforming the third layer into a layer of a second conductivity type, which is opposite to the first conductivity type; and forming a second semiconductor region of the first conductivity type, comprising the other of said collector region and said emitter region, on a part of the base region.