Patent · US Expired

Silicon nitride and silicon oxide etchant

US4269654A · kind A · utility

43Cited by
6References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 9, 1979
Grant dateMay 26, 1981
Priority date
Expiry dateMay 9, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/978
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

An etching solution for etching composite structures of silicon nitride on silicon oxide on silicon substrates which etches the silicon nitride at a rate equal to or faster than the silicon oxide which comprises concentrated aqueous hydrogen fluoride in a high boiling, organic solvent.

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