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. 02, 2014
Filed:
Jun. 18, 2012
Claudius Feger, Poughkeepsie, NY (US);
Mark H. Mcleod, Poughkeepsie, NY (US);
Jae-woong Nah, New York, NY (US);
Eric D. Perfecto, Poughkeepsie, NY (US);
Claudius Feger, Poughkeepsie, NY (US);
Mark H. McLeod, Poughkeepsie, NY (US);
Jae-Woong Nah, New York, NY (US);
Eric D. Perfecto, Poughkeepsie, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Solder bumps of uniform height are provided on a substrate through the use of injection molded solder. Copper pillars or ball limiting metallurgy are formed over I/O pads within the channels of a patterned layer of photoresist. Solder is injected over the pillars or BLM, filling the channels. The solder, which does not contain flux, is allowed to solidify. It forms a plurality of solder structures (bumps) of equal heights. Solder injection and solidification are preferably carried out in a nitrogen environment or a forming gas environment. Molten solder can be injected in channels formed in round wafers without spillage using a carrier assembly that accommodates such wafers and a fill head.