Patent · US Expired

Soluble fluorinated cycloalkane sulfonate surfactant additives for NH.sub.4

US4620934A · kind A · utility

11Cited by
3References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 13, 1985
Grant dateNov 4, 1986
Priority date
Expiry dateMay 13, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/31111
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Silicon dioxide etching solutions with soluble surfactant additives are provided. The improved silicon dioxide etchants are produced by adding soluble fluorinated surfactant additives to standard oxide etchants in the manufacture of integrated circuits. The surfactants found effective in accordance with the invention are referred to as fluorinated cycloalkane sulfonates and fluorinated cycloalkene sulfonates and have the general formula ##STR1## where X is F, H, Cl, OH, SO.sub.3 A or R and Y is F, H, OH, R or be omitted and thereby impart a double bond; wherein R is a 1 to 4 fluoroalkyl group; and wherein n has a value of up to 6. A represents as the cation group may be NH.sub.4.sup.+, H.sup.+, Na.sup.+, K.sup.+, Li.sup.+, R.sup.+ or organic amine cations.

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