Patent · US Expired

Nonvolatile semiconductor memory devices

US4011576A · kind A · utility

14Cited by
2References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 25, 1975
Grant dateMar 8, 1977
Priority date
Expiry dateAug 25, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D30/69
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A nonvolatile semiconductor memory device of the type known as an insulated gate field effect transistor, in which a thick gate insulating layer overlaps the source and drain regions formed in a substrate. The surface of the substrate underlying the thick gate insulating layer is doped lightly with impurities having opposite conductivity relative to the substrate.

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