DEVICE AND METHOD FOR POLISHING SEMICONDUCTOR SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To uniformly flatten the front surface of a film to be polished, by preventing a situation in which the polishing speed is different according to the part of the film to be polished formed on a wafer. SOLUTION: A film to be polished of a wafer 13 is polished by being pressed in the first range 12a of a polishing pad 12 to which abrasive materials 15 are to be supplied when it is rotated. An annular dummy material to be polished 17A made of the same material as the film to be polished of the wafer 13 is held by a dummy holding tool 18 and polished by being pressed to the second range 12b positioned on the opposite side of the center of the first range 12a on the polishing pad 12 with respect to the center. Therefore, the sum of the time in which the polishing pad 12 is brought in contact with the film to be polished of the wafer 13 and the time in which the polishing pad 12 is brought in contact with the surface to be polished of the dummy material to be polished 17B is uniformized.