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:
Mar. 16, 2010
Filed:
Oct. 03, 2006
Makoto Tsunekawa, Ibaraki, JP;
Makoto Tsunekawa, Ibaraki, JP;
Nitto Denko Corporation, Osaka, JP;
Abstract
The present invention provides a process for producing a wiring circuit board which can be inhibited from developing whiskers and can be reduced in the unevenness of connectivity with electronic parts while retaining the connectivity. According to the present invention, a wiring patterncomprising a thin metal filmand a conductor layeris formed on a base insulating layer BIL. A tin-plated layeris formed by electroless plating so as to coat the wiring patterntherewith. The wiring patternand the tin-plated layerare then subjected to a heat treatment. The heat treatment temperature and heat treatment period are regulated to 175 to 225° C. and 2 to 10 minutes, respectively. By the heat treatment, a mixture layercomprising copper and tin is formed. Thereafter, a solder resist SOL is formed over the base insulating layer so as to cover the wiring patternand tin-plated layerin given regions. Subsequently, the solder resist SOL is subjected to a heat curing treatment.