The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 18, 1990
Filed:
May. 31, 1988
Madan M Nanda, Reston, VA (US);
Steven L Peterman, Manassas, VA (US);
David Stanasolovich, Manassas, VA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A process for defining vias through a polyimide and silicon nitride layer is disclosed. After the deposition of a first layer of silicon nitride and a second layer of polyimide, a layer of photoresist capable of producing negatively sloped walls is then lithographically defined with a pattern of vias. After the photoresist is developed, the polyimide layer is etched with a CF.sub.4 O.sub.2 gas mixture using the developed photoresist layer as etch mask. The silicon nitride layer is then etched with a CF.sub.4 /H.sub.2 gas mixture using the etched polyimide layer as an etch mask.