Dressing apparatus and dressing method of polishing pad of double-side polishing apparatus

摘要

To provide a dressing apparatus capable of uniformly dressing a polishing pad. The apparatus includes first and second dressing grind stones 51 and 52 which grind polishing pads 17 and 18 by moving in a radial direction of upper and lower polishing plates 12 and 14 while abutting on corresponding polishing pads 17 and 18, in which the first and second dressing grind stones 51 and 52 are set so as to have: an inner side region portion P; an outer side region portion Q; and an intermediate region portion R, wherein the length of each of the inner side region portion P and the outer side region portion Q extending in a circumferential direction of the polishing plates 12 and 14 is longer than the length of the intermediate region portion R extending in a circumferential direction of the polishing plates.