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:
Jun. 04, 2002
Filed:
Mar. 15, 2000
Frank J. Downes, Jr., Vestal, NY (US);
Donald S. Farquhar, Endicott, NY (US);
Robert M. Japp, Vestal, NY (US);
William J. Rudik, Vestal, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Reliability of circuit packaging while accommodating larger chips and increased temperature excursions is achieved by use of compliant pads only at the locations of connections between packaging levels, preferably between a laminated chip carrier and a printed circuit board. The invention allows the coefficient of thermal expansion of the chip carrier to be economically well-matched to the CTE of the chip and accommodation of significant differences in CTEs of package materials to be accommodated at a single packaging level. The compliant pads are preferably of low aspect ratio which are not significantly deflected by accelerations and can be formed on a surface or recessed into it. Connections can be made through surface connections and/or plated through holes. Connection enhancements such as solder wettable surfaces or dendritic textures are provided in a conductive metal or alloy layer over a compliant rubber or elastomer layer which may be conductive or non-conductive.