Patent · US Expired

Two-step plasma process for selective anisotropic etching of polycrystalline silicon without leaving residue

US4502915A · kind A · utility

21Cited by
1References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 23, 1984
Grant dateMar 5, 1985
Priority date
Expiry dateJan 23, 2004

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/32137
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

The disclosure relates to a two-step for selective anisotropic etching of polycrystalline silicon having a silicon dioxide base thereunder and an exposed opposing face with contaminants thereon including silicon dioxide without leaving a residue wherein the silicon is initially etched with a non-selective etchant for a distance below all contaminants and then an etchant used is a highly anisotropic selective polycrystalline silicon etchant.

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