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:
Dec. 27, 2005
Filed:
Sep. 02, 2003
Christo P. Bojkov, Plano, TX (US);
Diane L. Arbuthnot, Plano, TX (US);
Robert F. Kunesh, Plano, TX (US);
Christo P. Bojkov, Plano, TX (US);
Diane L. Arbuthnot, Plano, TX (US);
Robert F. Kunesh, Plano, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A method for preparing a bonding pad on an integrated circuit wafer by the steps of depositing a conductive seed layer () on the bonding pad; depositing a metal layer (, and) over a portion of the conductive seed layer; and immersing the wafer in an etchant solution () to remove the portion of the seed layer not covered by the metal layer. The etchant solution contains a chelating agent that bonds ions from the seed layer. When the seed layer is copper or a refractory metal, and the metal layer is gold or palladium, the preferred chelating agent is selected from, but is not limited to, but is not limited to, the families of ethylenediaminetetraacetic acids (EDTA), 8-hydroxy-quinolines, including 8-hydroxy-quinoline-5-sulfonic acid, porphyrins, and phthalocyanines.