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. 08, 2006
Filed:
Jan. 29, 2004
David Vincent Caletka, Apalachin, NY (US);
Krishna Darbha, Johnson City, NY (US);
Donald W. Henderson, Ithaca, NY (US);
Lawrence P. Lehman, Endicott, NY (US);
George Henry Thiel, Endicott, NY (US);
David Vincent Caletka, Apalachin, NY (US);
Krishna Darbha, Johnson City, NY (US);
Donald W. Henderson, Ithaca, NY (US);
Lawrence P. Lehman, Endicott, NY (US);
George Henry Thiel, Endicott, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Solder balls such as, low melt C4 solder balls, undergo volume expansion during reflow, such as may occur during attachment of chip modules to a PCB. Where the solder balls are encapsulated, expansion pressure can cause damage to device integrity. A volume expansion region in the semiconductor chip substrate beneath each of the solder balls accommodated this volume expansion. Air-cushioned diaphgrams, deformable materials and non-wettable surfaces may be used to permit return of the solder during cooling to its original site. A porous medium with voids sufficient to accommodate expansion may also be used.