SIGE HETEROJUNCTION BIPOLAR TRANSISTOR WITH SHALLOW OUT-DIFFUSED P+ EMITTER REGION

摘要

A pnp SiGe heterojunction bipolar transistor (HBT) (300) reduces the rate that p-type dopant atoms in the p+ emitter (310) of the transistor out diffuse into a lowly-doped region of the base (150) of the transistor by epitaxially growing the emitter to include a single-crystal germanium region (316) and an overlying single-crystal silicon region (318).