| 摘要 |
PROBLEM TO BE SOLVED: To prevent polishing irregularity of a wafer by providing a rotational drive means mounted in a support base part to rotate a polishing surface plate around an axial line orthogonal to a polishing surface serving as the center relating to the support base part. SOLUTION: A rotational drive means 25 is mounted in a support base part, a polishing surface plate 10 is rotated around an axial line serving as the center relating to this support base part 22. In a circular motion device 32, the support base part 22 makes a circular motion without rotating on its own axis in a surface parallel to a polishing surface 10a relating to a base 30. This circular motion device 32 comprises an eccentric arm 34 and a circular motion motor 36. This circular motion is a motion generating an equal speed in any point on the polishing surface plate 10, any point of a wafer 20 can be polished by an equal condition. Accordingly, a surface of the wafer 20 can be very uniformly accurately polished. |
