SUB-CARRIER, POLISHING DEVICE WITH SUB-CARRIER, AND MANUFACTURE OF WAFER USING IT

摘要

PROBLEM TO BE SOLVED: To improve the uniformity of the polishing face and productivity by slightly tapering the outer circumferential face of a wafer. SOLUTION: A polishing device comprises a platen having a polishing cloth (pad) stuck to its upper surface and rotating and a sub-carrier 4 holding a wafer W, a material to be polished in such a state as pressurizing it towards the polishing cloth, while rotating. The sub-carrier 4 is provided with a cylindrical retainer ring (guide ring) 12 in the outer circumferential end so that the wafer W is not detached from the bottom face of the sub-carrier 4 during polishing. The outer circumference of the sub-carrier 4 is machined so as to form a taper part of the width 6 mm and the height 0.010 mm in the outer circumferential side in the surface of the water W side. This constitution can ease the pressure distribution in the outer circumference and consequently provide the wafer W with high flatness.