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

摘要

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