Patent · US Expired

Plasma etch process for single-crystal silicon with improved selectivity to silicon dioxide

US4468285A · kind A · utility

19Cited by
2References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 22, 1983
Grant dateAug 28, 1984
Priority date
Expiry dateDec 22, 2003

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/3065
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A plasma etching composition is set forth which comprises chlorine in an amount from about 40% to about 90%, a shape modifier species in an amount from about 10% to about 60%, and an etching selectivity enhancer in an amount sufficient to render the composition at least about 10 times as effective for etching a wafer as for etching a masking layer, the above percents being by mole. The composition is useful for plasma etching of a semiconductor wafer masked with a masking layer having an opening therethrough exposing a portion of the wafer which is to be etched in order to form a depression of a desired depth. This allows depressions of increased depth to be formed in wafers without increasing the thickness of the masking layer.

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