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. 16, 2009
Filed:
Feb. 28, 2006
Yumi Imamura, Tokyo, JP;
Kenji Yamamoto, Tokyo, JP;
Tomohiro Murakami, Tokyo, JP;
Renesas Technology Corp., Tokyo, JP;
Abstract
It is suppressed that a whisker occurs on a lead for external connection. A lead for external connection is formed of the alloy (42Alloy) of Fe and Ni, and a plating film which includes alloy of Sn and Cu is formed on the surface. Next, using a heat-treat furnace, the heat treatment at the temperature beyond melting-point Tof the plating film is performed, and the plating film is melted. At this time, the temperature beyond Tis held for 20 seconds or more. The grain boundary of the plating film can be vanished by the above-mentioned heat treatment. Hereby, the internal stress of the plating film can be eased, and the generation of the whisker can be suppressed.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile