Methods and Apparatus for Bipolar Junction Transistors and Resistors

摘要

Methods and apparatus for bipolar junction transistors (BJTs) are disclosed. A BJT comprises a collector made of p-type semiconductor material, a base made of n-type well on the collector; and an emitter comprising a p+ region on the base and a SiGe layer on the p+ region. The BJT can be formed by providing a semiconductor substrate comprising a collector, a base on the collector, forming a sacrificial layer on the base, patterning a first photoresist on the sacrificial layer to expose an opening surrounded by a STI within the base; implanting a p-type material through the sacrificial layer into an area of the base, forming a p+ region from the p-type implant; forming a SiGe layer on the etched p+ region to form an emitter. The process can be shared with manufacturing a polysilicon transistor up through the step of patterning a first photoresist on the sacrificial layer.

主权项

1. A bipolar junction transistor (BJT) comprising:
an emitter disposed in a semiconductor substrate of a first semiconductor material, the emitter comprising:
a doped region; anda first contact layer of a second semiconductor material disposed on the doped region; a base disposed under the emitter, the base having a first base portion extending above a bottom surface of the emitter, the first base portion laterally spaced apart from the emitter; a collector disposed under the base and extending laterally past edges of the base; and a first isolation structure disposed between and separating the first base portion and the emitter.