IP Library Granted Patent US 4,920,028
Granted Patent Utility
US 4,920,028 · App. 07/227,404

High contrast high thermal stability positive photoresists with mixed cresol and hydroxybenzaldehyde prepared novolak and photosensitive diazoquinone

Inventors: Richard M. Lazarus, Randall Kautz, Sunit S. Dixit
Patented Case View Patent ↗
Granted: Apr 24, 1990 Filed: Aug 2, 1988
Inventors
Richard M. Lazarus
Randall Kautz
Sunit S. Dixit
Assignee (at issue)
Morton Thiokol

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Quick Facts
Patent No.
US 4,920,028
App. No.
07/227,404
Filed
1988-08-02
Granted
1990-04-24
Kind
A