| 摘要 |
PROBLEM TO BE SOLVED: To polish a semiconductor wafer uniformly over its entire surface using a polishing cloth to make the surface smooth and avoid causing localized polishing, by pressing the wafer through combined backing pads mutually different in hardness. SOLUTION: In the polishing for a wafer with use of a polishing cloth, an inner and outer pads 2 and 3 mutually different in hardness form a backing pd 1. As a result, the pressing force exerted on the wafer is partly controllable to make it possible to uniformly polish it over the entire surface. The cushion effect at the wafer's marginal area is apt to appear at the polishing cloth, using an outer pad 3 having a higher hardness than of the inner pad 2, and hence the localized polishing at the wafer's marginal area is suppressed. And at the central area of the wafer, this effect is apt to appear at the backing pad and hence the dishing at the central area of the wafer is suppressed. |
