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:
Sep. 19, 2000
Filed:
Sep. 03, 1999
Applicant:
Inventors:
Christina M Boyko, Endicott, NY (US);
Anthony P Ingraham, Endicott, NY (US);
Voya R Markovich, Endwell, NY (US);
David J Russell, Apalachin, NY (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ; H01L / ;
U.S. Cl.
CPC ...
438106 ; 438108 ; 438612 ; 438613 ;
Abstract
A solder interconnection uses preferably lead-rich balls for making a low temperature chip attachment directly to any of the higher levels of packaging substrate. After a solder ball has been formed using standard processes, a ball limiting metal mask is formed using photoresist. A thin cap layer of preferably pure tin is deposited on a surface of the solder balls using a tin aqueous immersion process.