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:
Jun. 20, 2006
Filed:
Mar. 04, 2005
Larry A. Spiegel, San Luis Obispo, CA (US);
Larry A. Spiegel, San Luis Obispo, CA (US);
Strasbaugh, San Luis Obispo, CA (US);
Abstract
A wafer carrier for controlling the edge effect during chemical mechanical planarization. A first bladder is disposed within the retaining ring to control the height of the retaining ring relative to the bottom surface of the wafer carrier. A second bladder is disposed within the carrier such that if the pressure in the bladder is regulated, the amount of force on the edge of the wafer changes. If a polishing process would cause material near the edge of the wafer to be removed at a higher rate than from the rest of the wafer, then the pressure is regulated within the bladder to reduce the force against the edge of the wafer. By reducing the force against the edge of the wafer, material is removed from the front side of the wafer at a uniform rate.