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. 19, 2001
Filed:
Aug. 13, 1999
David R. Baker, Cupertino, CA (US);
John Grange, San Jose, CA (US);
David Light, Los Gatos, CA (US);
Hung-Ming Wang, San Jose, CA (US);
Tessera, Inc., San Jose, CA (US);
Abstract
Metal leads are formed on a copper conductive layer by applying a first resist and a main resist over the first resist, and forming aligned openings in these resist. A bottom layer of cover metal such as gold is plated onto the copper conductive layer in these openings, followed by a principal metal such as copper. The main resist is then removed so as to expose edges of the principal metal layer. A jacket of cover metal is plated onto the exposed edges and surfaces of the principal metal layer. During this stage, the first resist prevents deposition of the cover metal except on the leads. The jacket merges with the bottom layer of cover material, so as to form a continuous coating extending around the perimeters of the leads. The first resist is removed, and the conductive layer is etched away. The cover metal protects the principal metal during the etching stage.