BiCMOS devices with a self-aligned emitter and methods of fabricating such BiCMOS devices

摘要

A method of fabricating an heterojunction bipolar transistor (HBT) structure in a bipolar complementary metal-oxide-semiconductor (BiCMOS) process selectively thickens an oxide layer overlying a base region in areas that are not covered by a temporary emitter and spacers such that the temporary emitter can be removed and the base-emitter junction can be exposed without also completely removing the oxide overlying the areas of the base region that are not covered by the temporary emitter or spacers. As a result, a photomask is not required to remove the temporary emitter and to expose the base-emitter junction.