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:
Mar. 11, 2003
Filed:
Oct. 30, 2001
Guido Wenski, Burghausen, DE;
Thomas Buschhardt, Burghausen, DE;
Heinrich Hennhöfer, Wohnsitz, DE;
Bruno Lichtenegger, Wohnsitz, DE;
Wacker Siltronic Gesellschaft für Halbleitermaterialien AG, Burghausen, DE;
Abstract
A process for the surface polishing of a silicon wafer, includes the successive polishing of the silicon wafer on at least two different polishing plates covered with polishing cloth, with a continuous supply of alkaline polishing abrasive with SiO constituents, an amount of silicon removed during the polishing on a first polishing plate being significantly higher than on a second polishing plate, with the overall amount of silicon removed not exceeding 1.5 &mgr;m. A polishing abrasive ( ), then a mixture of a polishing abrasive ( ) and at least one alcohol, and finally ultrapure water ( ) are added to the first polishing plate, and a mixture of a polishing abrasive ( ) and at least one alcohol and then ultrapure water ( ) are added to the second plate.