Patent · US Expired

Combined bipolar-field effect transistor resurf devices

US4639761A · kind A · utility

127Cited by
7References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 25, 1985
Grant dateJan 27, 1987
Priority date
Expiry dateOct 25, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S257/901
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A combined bipolar-field effect transistor RESURF device includes a lightly-doped epitaxial buried layer of a first conductivity type located between a semiconductor substrate of the first conductivity type and an epitaxial surface layer of a second conductivity type opposite to that of the first. The doping concentration and thickness of the epitaxial surface layer are selected in accordance with the Reduced Surface Field (RESURF) technique. A highly-doped buried region of the second conductivity type is located beneath the base region of the device and is sandwiched between the epitaxial buried layer and the epitaxial surface layer. The advantages of such a device include a substantially reduced "on" resistance, a more compact and flexible configuration, improved switching characteristics, reduced base device current requirements, and improved isolation. The device may be further enhanced by providing a buried annular region of the first conductivity type around and in contact with the buried region, and a surface-adjoining annular region of the first conductivity may be provided adjacent the base region.

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