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. 18, 2001
Filed:
Oct. 13, 1999
Mike L. Bowman, Chandler, AZ (US);
Tim Dyer, Tempe, AZ (US);
Gene Hempel, Gilbert, AZ (US);
Craig M. Howard, Gilbert, AZ (US);
Yushin Son, Chandler, AZ (US);
SpeedFam-IPEC Corporation, Chandler, AZ (US);
Abstract
A method for planarizing the surface of a wafer against a polishing pad includes the steps of securing the wafer in a carrier, pressing the wafer against the polishing pad, rotating both the wafer and pad, and moving the wafer across the polishing pad to create one or more geometric patterns relative to the pad. Geometric patterns employed by the present method include a 'figure eight', an elliptical pattern, and a peanut-shaped pattern. In one embodiment of the invention, both a 'figure eight' pattern and an elliptical pattern are used during a single planarizing operation. Bezier splines (curves) are used to create geometric patterns employed by the planarizing process. The use of Bezier splines requires that only two endpoints and two control points be stored in a memory device to represent the entire curve between the two endpoints, thus reducing the amount of data that has to be stored and transferred in order to operate a programmable wafer carrier in accordance with the present method.