Patent · US Expired

Method of making a bipolar transistor

US4504332A · kind A · utility

37Cited by
6References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 3, 1982
Grant dateMar 12, 1985
Priority date
Expiry dateMay 3, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/969
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

This invention provides a method for manufacturing a bipolar transistor which comprises steps of selectively forming in the surface of a semiconductor substrate an embedded layer of a conductivity type opposite to that of the substrate, covering the substrate with an insulating layer doped, at the surface thereof with an impurity in the superficial region thereof, removing by etching the insulating layer to form an opening portion through which part of the embedded layer is exposed, simultaneously forming by epitaxial growth a single-crystal semiconductor layer of the same conductivity type as that of the embedded layer on the embedded layer at the opening portion and a polycrystalline semiconductor layer on the insulating layer, diffusing by heating the impurity in the insulating layer into the polycrystalline semiconductor layer to provide a conductivity type opposite to that of the single-crystal semiconductor layer, and successively forming an internal base region and an emitter region in the single-crystal semiconductor layer. The invention also provided a bipolar transistor manufactured by the aforementioned method.

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