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:
Apr. 18, 2006
Filed:
Dec. 20, 2004
Akira Horiguchi, Kashiwara, JP;
Shoji Nakao, Tokyo, JP;
Akira Horiguchi, Kashiwara, JP;
Shoji Nakao, Tokyo, JP;
Kashiwara Machine Mfg. Co., Ltd., Kashiwara, JP;
Sumitomo Mitsubishi Silicon Corporation, Tokyo, JP;
Abstract
In order to improve a flatness of a work in single wafer type double-side polishing in which one wafer is polished with one carrier, a carrier larger in diameter than upper and lower surface plates that rotate is inserted between the surface plates, and a wafer smaller in diameter than the surface plates is held with the carrier. The carrier is rotated by plural eccentric gears that mesh with external gear teeth formed on the outer peripheral surface of the carrier at plural positions along a circumferential direction thereof and revolve around positions spaced from the centers as centers in synchronism with each other or one another at the plural positions of meshing. The carrier rotates about its center and moves circularly around the center of the surface plates spaced from the center thereof. The upper surface plate is reciprocated in a direction perpendicular to the central axis when required. Geometrical motion loci of points on the wafer are complex and peripheral speeds alter to large extents to thereby enhance equalization of peripheral speeds of points on the wafer to a higher level to thereby improve a flatness.