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:
Sep. 27, 2011
Filed:
Apr. 27, 2007
Carla A. Bailey, Poughkeepsie, NY (US);
Camille P. Bowne, Poughkeepsie, NY (US);
Krystyna W. Semkow, Poughquag, NY (US);
Carla A. Bailey, Poughkeepsie, NY (US);
Camille P. Bowne, Poughkeepsie, NY (US);
Krystyna W. Semkow, Poughquag, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A chemical etchant containing hydrogen peroxide and phosphate ions at a controlled pH is provided for selectively etching metals in the presence of one or more metals not to be etched. The etchant is useful in the fabrication of semiconductor components particularly for forming capture pads where TiW is used as a barrier layer for a copper, copper/nickel pad, or copper/nickel alloy pad. A commercial hydrogen peroxide solution is preferred to which has been added phosphoric acid as a source of phosphate ions and KOH as the pH adjuster.