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. 02, 2007
Filed:
Nov. 04, 2003
Takuji Hayama, Tokyo, JP;
Masafumi Inoue, Tokyo, JP;
Kunihiko Sakurai, Tokyo, JP;
Ebara Corporation, Tokyo, JP;
Abstract
A polishing apparatus has a polishing table () with a polishing surface () attached thereon, and a top ring () for pressing a workpiece (W) against the polishing surface (). The top ring () has a housing () and a retainer ring () vertically movable in the housing () for holding an outer circumferential edge of the workpiece (W). The polishing apparatus includes a vertically moving mechanism operable to vertically move the top ring (), a bracket () vertically movable together with the top ring (), a stopper () adjustable in vertical position to prevent downward movement of the bracket (), and a sensor () for detecting a distance between the stopper () and the bracket (). The polishing apparatus also includes a control unit () operable to adjust the stopper () in vertical position when the retainer ring () is brought into contact with the polishing surface () while a lower surface of the housing () of the top ring () is located, at a predetermined height from the polishing surface () so that the distance between the stopper () and the bracket () is equal to a difference between a height of the lower surface of the housing () from the polishing surface () at the time of polishing and the predetermined height.