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. 27, 2000
Filed:
Aug. 10, 1998
Tokyo Seimitsu Co., Ltd., Tokyo, JP;
Abstract
The first air guide groove is formed at the bottom of a carrier along the inner circumference of a circle whose radius corresponds to the maximum radius of a wafer. The air is supplied to the outer periphery of the wafer through the first air guide groove to form a pressure air layer between the carrier and the wafer. The formation of the pressure air layer makes the air pressure applied to the wafer uniform on the entire surface of the wafer, and thus, the wafer can be polished under a uniform pressure force. The second air guide groove is formed along the inner circumference of a circle whose radius corresponds to the minimum radius of the wafer, and therefore, the wafer with an orientation flat or notch can be polished under a uniform pressure force.