To improve the flatness of a work on the whole after polishing by equalizing the working pressure during the polishing over the work.
This work holding mechanism for holding the work in a plane vertical to the pressing direction comprises a pressing board 13 abutted on a rear face of a central part of the work 3, a pressing base 17 abutted on a rear face of a peripheral edge part of the work, a retainer ring 21 surrounding an outer edge of the work, diaphragms 16, 20, 22 holding the pressing board 13, the pressing base 17 and the retainer ring movably in the pressing direction, and balloon-shaped elastic bodies capable of being abutted on rear faces of the pressing board, the pressing base and the retainer ring, and the work 3 is pressed to a polishing pad 28 through the pressing board 13 and the pressing base 17, and the retainer ring 21 is pressed to the polishing pad 28 by expanding elastic sheets 15, 19, 23 of the balloon-shaped elastic bodies by the pressure of the fluid supplied to space parts 100, 102, 104 of the balloon-shaped elastic bodies.
YASUHIRA NOBUO
SHINGU KATSUKI
