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:
Apr. 17, 2007
Filed:
Jul. 16, 2004
Saravuth Sirinorakul, Bangna, TH;
Arlene V. Layson, Bangkok, TH;
Somchai Nondhasitthichai, Bangkok, TH;
Yee Heong Chua, Singapore, SG;
Saravuth Sirinorakul, Bangna, TH;
Arlene V. Layson, Bangkok, TH;
Somchai Nondhasitthichai, Bangkok, TH;
Yee Heong Chua, Singapore, SG;
NS Electronics Bangkok (1993) Ltd., Bangkok, TH;
Abstract
A semiconductor package contains a metal leadframe that has been specially treated by roughening it with a chemical etchant. The roughening process enhances the adhesion between the leadframe and the molten plastic during the encapsulation of the leadframe and thereby reduces the tendency of the package to separate when exposed to moisture and numerous temperature cycles. In one embodiment, the leadframe made of copper is roughened with a chemical etchant that contains sulfuric acid and hydrogen peroxide.