Patent · US Expired

Method of etching films of silicon nitride and silicon dioxide

US3979241A · kind A · utility

40Cited by
4References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 29, 1973
Grant dateSep 7, 1976
Priority date
Expiry dateMar 29, 1993

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/01033
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

An etching liquid comprises ammonium fluoride or alkali fluoride dissolved in a polyvalent or higher alcohol.

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