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. 08, 1997
Filed:
Apr. 16, 1996
Isao Nagahashi, Ayase, JP;
Yoshishige Takahashi, Nagaoka, JP;
Speedfam Company Limited, Tokyo, JP;
Abstract
A polishing device is formed of a pair of rotatable and elevatable upper supporting members provided with ring shape polishing pads at lower surface peripheries thereof, a pair of rotatable lower supporting members provided with ring shape polishing pads at upper surface peripheries thereof, a rotatable and elevatable disc holding device for holding a disc to be polished, and an arm for supporting the upper supporting members and the disc holding device. The polishing device further includes driving devices for rotating the upper supporting members, the lower supporting members and the disc holding device, respectively. The disc is independently rotated in a direction opposite to a rotating direction of the upper and lower supporting members to improve polishing efficiency. By setting rotating speeds of the supporting members and the disc, a regular working mark can be formed on the disc.