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:
Apr. 18, 2000
Filed:
Nov. 18, 1997
Hormazdyar Minocher Dalal, Milton, NY (US);
Gene Joseph Gaudenzi, North Salem, NY (US);
Frederic Robert Pierre, Mennecy, FR;
Georges Henri Robert, Baulne, FR;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A material deposition process is disclosed in which apertures of a contact mask used therein have a constricted opening terminating in a `knife edge` in a sidewall thereof near the top mask side, especially within the top 25% of the mask thickness above the substrate. A process is disclosed in which the mask, in addition, has apertures which have larger dimension lower openings on a bottom side of the mask contacting the substrate than constricted openings near the top side of the mask. Single solder bump and 'bump on bump' over BLM (ball limiting metallurgy) processes are disclosed which utilize such contact mask to reduce the damage and detaching of such features during processing and subsequent handling.