Patent · US Expired

Control of substrate injection in lateral bipolar transistors

US4507848A · kind A · utility

4Cited by
13References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 22, 1982
Grant dateApr 2, 1985
Priority date
Expiry dateNov 22, 2002

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D10/60
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for fabricating a semiconductor structure which reduces substrate current injection from lateral bipolar transistors. A buried layer of a first conductivity type is formed in a semiconductor substrate of opposite conductivity. An epitaxial layer of the first conductivity type is formed such that at least a portion of the epitaxial layer overlies the buried layer. Isolation oxide regions are formed in a epitaxial layer. The isolation oxide regions extend to the substrate to define an island of electrically isolated epitaxial material. A selected impurity of the first conductivity type is introduced into that portion of the epitaxial layer beneath the to-be-formed lateral transistor. The lateral transistor is formed in the epitaxial layer.

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