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:
Jul. 29, 2003
Filed:
Jun. 30, 2000
Jose L. Cruz, Essex Junction, VT (US);
Cuc K. Huynh, Jericho, VT (US);
Timothy C. Krywanczyk, Essex Junction, VT (US);
Douglas K. Sturtevant, Essex Junction, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A CMP slurry for and method of polishing a semiconductor wafer during formation of metal interconnects are disclosed. The present invention utilizes a first slurry comprising a first oxidizer, preferably ferric nitrate, to remove the excess metal of the metal interconnect but which leaves the metal residues on the surface of the wafer. A second slurry comprising another oxidizer, preferably potassium iodate solution, having a greater affinity to both the metal residue and the liner material than the underlying dielectric is used to remove the metal residue and liner material with significantly reduced scratching of the underlying dielectric. The more robust metal interconnects formed utilizing the present invention is effective in lowering the overall resistance of a wafer, reducing the number of shorts, and provides greater protection of the underlying dielectric. Overpolishing of the wafer and its associated problems are avoided.