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. 12, 2011
Filed:
Nov. 05, 2009
Akira Fukuda, Fujisawa, JP;
Yoshihiro Mochizuki, Fujisawa, JP;
Kazuto Hirokawa, Fujisawa, JP;
Ebara Corporation, Tokyo, JP;
Abstract
A polishing apparatus polishes wafers at a high yield rate even if roll-off exists. The polishing apparatus polishes a wafer by applying a pressure between a polishing member (polishing pad) and the wafer held by a holding member (top ring) and moving the polishing member relative to the wafer. The polishing apparatus includes a top ring for holding the wafer, a pressure adjusting mechanism for adjusting a supporting pressure with which the wafer is supported on a supporting surface by a retainer ring, and a control unit for controlling the pressure adjusting mechanism to bring the supporting pressure to a desired pressure based on a roll off quantity of the wafer. The top ring comprises an air bag for pressing the wafer against the polishing pad, a retainer ring which surrounds the wafer, and an air bag for pressing the retainer ring.