US 6,664,610 B2 · Bipolar transistor and the method of manufacturing the same

Abstract

This invention provides a new configuration and manufacturing method of the hetero-junction bipolar transistor. According to the invention, the HBT comprises a semi-insulating InP substrate, a buffer layer on the substrate, a sub-collector layer, a collector layer, a base layer, an emitter layer, and an emitter contact layer These layers are sequentially grown on the buffer layer. Since a pre-processing of forming two depressions in the sub-collector layer before growing the collector layer, the top surface of the emitter layer becomes planar surface. This results on the reduction of pits induced in the etching of the emitter contact layer, thus enhances the reliability and the high frequency performance of the HBT.

Claims11

Dependent claims

A bipolar transistor on a semiconductor comprising:

a sub-collector layer formed on the substrate, the sub-collector layer having a pair of edges extending along a predetermined axis of the substrate;
a collector layer on the sub-collector layer, the collector layer overlapping the pair of edges of the sub-collector layer and having a first gap energy;
a base layer having a second band gap energy on the collector layer;
an emitter layer having a third band gap energy on the base layer, the emitter layer having a top surface exposed thereof and a first pair of edges;
and
an emitter contact layer on the emitter layer, the emitter contact layer having a second pair of edges apart from the first pair of edges of the emitter layer,
wherein the top surface of the emitter layer is planar.

4 more elements

Dependencies are inferred from the claim text.

Bipolar transistor and the method of manufacturing the same

Life of this patent

Bipolar transistor and the method of manufacturing the same

Life of this patent

Abstract

Claims11