Patent · US Expired

Method for fabricating heterojunction bipolar transistor

US5798277A · kind A · utility

26Cited by
3References
4Claims
0Family size

Assignees

Inventors

Key dates

Filing dateOct 15, 1996
Grant dateAug 25, 1998
Priority date
Expiry dateOct 15, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S148/072

Abstract

An improved method for fabricating a heterojunction bipolar transistor which includes the steps of forming a buried collector, a collector thin film, and a collector sinker on a semiconductor substrate in order, forming a first silicon oxide film, a base electrode polysilicon layer, a nitride film, and an oxidation film on a resulting substrate exposing the first silicon oxidation film, forming a spacer insulation film at the lateral side of the exposed region, and defining an activation region, exposing the collector thin film of the activation region using a mask, and forming an auxiliary lateral film for an isolation of the device, forming a selective collector region by ion-implantating a dopant to the activation region which is limited by the auxiliary lateral film, removing the auxiliary lateral film, etching the exposed portion in an anisotropic etching method, and forming a shallow trench for a device isolation, forming a polysilicon lateral film to have a height which is the same as the height of the base electrode polysilicon layer on the shallow trench, and forming a self-aligned base.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.