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:
Jul. 10, 2001
Filed:
Jul. 21, 1999
John Michael Cotte, New Fairfield, CT (US);
Madhav Datta, Hillsboro, OR (US);
Sung Kwon Kang, Chappaqua, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An array of C,solder bumps and a method for making is described incorporating an array of conductive areas on an electrical device, each conductive area having a layer of ball limited metalurgy at the device surface and two layers of solder having respective melting temperatures to form the C,structure. The method includes melting the second layer of solder in the down position or towards earth to form a C,solder ball or bump. The invention overcomes the problem of low temperature solder from wicking over the sidewall surfaces of the high melt solder of the C,structure and attacking the edges of the underlying seed layers of the ball limited metalurgy.