Patent · US Expired

Method of making semiconductor devices

US4379001A · kind A · utility

18Cited by
14References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 18, 1979
Grant dateApr 5, 1983
Priority date
Expiry dateJul 18, 1999

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/32155
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

In a semiconductor device such as a bipolar transistor and a field effect transistor of the type having a substrate, a doped polycrystalline silicon region selectively formed on the substrate and an insulating film overlying the polycrystalline silicon region, the region is shaped as mesa having side surfaces with a negative coefficient of gradient between the substrate and the top of the mesa.

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