Patent Number: 6,168,684

Title: Wafer polishing apparatus and polishing method

Abstract: A wafer polishing apparatus has a rotary polishing bed, an abrasive cloth provided on the polishing bed, an abrasive supply supplying abrasives to a surface of the abrasive cloth, a wafer depressor depressing the wafer onto the abrasive cloth at a predetermined pressure, a ring shaped retainer arranged surrounding the wafer and provided with a plurality of grooves extending between an inner peripheral edge and an outer peripheral edge on a surface contacting with the abrasive cloth, a rotary driver driving the wafer and the retainer on the abrasive cloth, and a rotation speed difference generator providing a difference of rotation speeds between the wafer and the retainer.

Inventors: Mitsuhashi; Hideo (Tokyo, JP), Ohi; Satoshi (Tokyo, JP), Yamamori; Atsushi (Tokyo, JP), Inaba; Shoichi (Tokyo, JP)

Assignee: NEC Corporation

International Classification: B24B 47/00 (20060101); B24B 47/10 (20060101); B24B 37/04 (20060101); C23F 001/02 (); B24B 005/00 (); B24B 029/00 ()

Expiration Date: 01/02/2018