Patent · US Expired

Method of fabricating bipolar transistor using self-aligned polysilicon technology

US5244822A · kind A · utility

2Cited by
7References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 8, 1992
Grant dateSep 14, 1993
Priority date
Expiry dateJan 8, 2012

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S148/011
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

In a bipolar transistor, having a micronized structure for a high-speed LSI, which is fabricated by a self-alignment technology, a barrier insulating film is buried in a portion around an emitter layer so as to be deeper than a junction level between an active base layer and a collector layer. When a polysilicon film pattern which defines an active base region and serves as a portion of a base electrode is formed on a wafer surface, a surface portion of a photoresist serving as an etching mask is converted to a carbonized layer by ion implantation. When a micronized emitter layer is formed by a polysilicon-emitter technology, ion implantation is performed before deposition of the polysilicon film or an impurity is doped in the polysilicon film simultaneously with deposition, and rapid thermal annealing is performed so as to activate the doped impurity.

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