Patent · US Expired

Differential etching of silicon nitride

US4956314A · kind A · utility

41Cited by
5References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 1989
Grant dateSep 11, 1990
Priority date
Expiry dateMay 30, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/31155
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for differentially etching silicon nitride, preferably formed in a hydrogen free environment, wherein hydrogen is implanted into various regions of the silicon nitride. The silicon nitride may then be etched by a number of different etchants, some of which will etch the implanted regions appreciably faster and others which will etch the non-implanted regions more quickly. This method is especially useful in the fabrication of self-aligned gate devices.

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