IP Library › Granted Patent US 4,938,841
Granted Patent Utility
US 4,938,841 · App. 07/429,560

Two-level lithographic mask for producing tapered depth

Inventors: Arie Shahar, Walter J. Tomlinson, III
Patented Case View Patent ↗
Granted: Jul 3, 1990 Filed: Oct 31, 1989
Inventors
Arie Shahar
Walter J. Tomlinson, III
Assignee (at issue)
Bell Communications Research, Inc.

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Quick Facts
Patent No.
US 4,938,841
App. No.
07/429,560
Filed
1989-10-31
Granted
1990-07-03
Kind
A