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:
Aug. 19, 2003
Filed:
Feb. 01, 2001
Frank D. Egitto, Binghampton, NY (US);
Edmond O. Fey, Vestal, NY (US);
Luis J. Matienzo, Endicott, NY (US);
David L. Questad, Vestal, NY (US);
Rajinder S. Rai, Johnson City, NY (US);
Daniel C. Van Hart, Conklin, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A metal alloy solder ball comprising a first metal and a second metal, the first metal having a sputtering yield greater than the second metal. The solder ball comprises a bulk portion having a bulk ratio of the first metal to the second metal, an outer surface, and a surface gradient having a depth and a gradient ratio of the first metal to the second metal that is less than the bulk ratio. The gradient ratio increases along the surface gradient depth from a minimum at the outer surface. The solder ball may be formed by the process of exposing the ball to energized ions of a sputtering gas for an effective amount of time to form the surface gradient.