For a semiconductor device including a bipolar transistor, the emitter, a heavily doped base region surrounding the emitter, and base and collector contact regions, (the collector including a buried layer at an epitaxial layer/substrate interface of the semiconductor body), are formed by employing, on...http://www.google.fr/patents/US4700456?utm_source=gb-gplus-shareBrevet US4700456 - Semiconductor device containing bipolar transistor formed by method including three photolithographic steps
Semiconductor device containing bipolar transistor formed by method ...
