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:
Oct. 14, 1997
Filed:
Dec. 06, 1995
William Francis Landers, Beacon, NY (US);
Matthew Jeremy Rutten, Milton, VT (US);
Thomas Robert Fisher, Jr, Beacon, NY (US);
Dean Allen Schaffer, South Burlington, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An improved Chemical Mechanical Planarization (CMP) method is provided for selectively removing a layer of metallization material such as tungsten or copper and a liner film such as Ti/Tin or Ta/TaN from the surface of an oxide layer of a semiconductor wafer. The method includes removing the metallization and liner layers with a first removal process which utilizes CMP polishing and an alumina-based slurry. The first removal process is stopped after the metallization layer is completely removed and before the liner film is completely removed. The remainder of the liner film is removed using a second removal process which includes CMP polishing using a neutral pH silica-based slurry which is selective to the liner film.