Patent ID: 9059138
Filing Date: 2015-06-16
Classification: H01L

Abstract:
1. A heterojunction bipolar transistor structure comprising: a semiconductor substrate having a sub-collector region of a first conductivity type therein; a collector region of a first conductivity type overlying a first portion of the sub-collector region, the collector region having a lower impurity concentration than the sub-collector region; an intrinsic base layer of a second conductivity type overlying at least a portion of the collector region; an extrinsic base layer adjacent to and electrically connected to the intrinsic base layer; an isolation region extending vertically between the extrinsic base layer and a second portion of the sub-collector region, a collector contact extending through a portion of the isolation region, wherein the collector contact penetrates through the extrinsic base layer; an emitter of the first conductivity type overlying a portion of the intrinsic base layer; and the collector contact electrically connected to the sub-collector region, the collector contact extending through at least a portion of the extrinsic base layer.