Patent · US Expired

Sulfonium salts and chemically amplified positive resist compositions

US5824824A · kind A · utility

19Cited by
4References
9Claims
0Family size

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Key dates

Filing dateNov 1, 1996
Grant dateOct 20, 1998
Priority date
Expiry dateNov 1, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/126
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

The invention provides a novel sulfonium salt having at least one acid labile group attached to a phenyl group in a molecule and a C.sub.2 -C.sub.20 alkylsulfonate or arylsulfonate anion whose alkyl or aryl has as a substituent an electron withdrawing group such as fluorine and nitro group. The novel sulfonium salt is effective for increasing the dissolution contrast between exposed and unexposed areas. Upon exposure, it generates a substituted alkyl or arylsulfonic acid which is a weak acid, minimizing the influence of side reaction and deactivation during PEB step. The sulfonium salt is useful in a chemically amplified positive resist composition which lends itself to fine patterning and features high resolution.

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