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:
Jan. 21, 2003
Filed:
Aug. 25, 2000
Other;
Abstract
A wafer-polishing head which has an increased flexible membrane life and improved wafer polishing accuracy has a principal head having a lower opening portion with an approximately circular shape. A flexible membrane which is positioned in the opening portion of the principal heal head for closing the opening portion and for holding a wafer W at the underside of an inward peripheral portion of the flexible membrane. A sealed pressurizing chamber is formed by closing the opening portion with the flexible membrane. A pressure regulator is provided for controlling the internal pressure of the pressurizing chamber . The flexible membrane is thicker in an outer peripheral portion thereof than in the inward peripheral portion which holds the wafer.