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Expired European patentEurope

Process for the preparation of low temperature silicon nitride films by photochemical vapor deposition

EP 0005491 B1 · Applicant: Hughes Aircraft Company

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Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

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Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed May 5, 1979 and granted November 4, 1981. A European patent lasts at most 20 years from filing, so its term ended May 5, 1999.
  • A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by November 5, 2004.
  • We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledMay 5, 1979
PublishedNovember 28, 1979
GrantedNovember 4, 1981
Term endedMay 5, 1999
Application numberEP 79101376
Classification (CPC)C23C16/482 +2 more

Timeline

Timeline From EPO dates

1980198219841986198819901992199419961998Application filedMay 5, 1979PublishedNov 28, 1979Patent grantedNov 4, 1981Term endedMay 5, 1999

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