| 摘要 |
PROBLEM TO BE SOLVED: To improve the uniformity in the dressing by arranging a plurality of abrasive grains to be contacted with a flat member to perform the dressing, on a plurality of approximately concentric circles of different diameters at approximately equal intervals. SOLUTION: The diamond abrasive grains 84 are formed into approximately regular octahedron, and buried in such manner that their upper surfaces are located in parallel with a surface of a fixed layer 86. That is, the upper surfaces of the abrasive grains 84 are placed approximately in parallel with a lower surface of an abrasive pad. A plurality of diamond abrasive grains 84 are placed on a circular pedestal 90, and arranged double on the approximately concentric circle with a wafer at approximately equal intervals. The diamond abrasive grains 84 have, for example, about 1 mm particle size, and a distance between the centers of the adjacent diamond abrasive gains 84 is determined to be 3 mm. A position of the concentric circle formed by the diamond abrasive grains 84 is determined to both inner and outer sides of the pedestal 90 (fixed layer 86) as much as possible. |
