Bipolar junction transistors and methods of manufacturing the same

摘要

A bipolar transistor includes a substrate having a collector region of a first conductivity type, a base layer of a second conductivity type extending horizontally over the collector region, and an emitter region of the first conductivity type at least partially contained in the base layer. The bipolar transistor also includes an emitter electrode confronting an upper surface of the emitter region, and a base electrode confronting an upper surface of the base layer. A vertical profile of at least a portion the base electrode is equal to or greater than a vertical profile of the emitter electrode.