| 摘要 |
<P>PROBLEM TO BE SOLVED: To polish a workpiece uniformly and suppress an increase in size of a device efficiently. <P>SOLUTION: A carrier 12 holding a wafer W is clamped with upper and lower polishing plates 14, 16 and the wafer W is polished from both upper and lower sides by rotational drive of these plates 14, 16. The carrier 12 comprising an external gear wheel is connected with an upper end of a main drive shaft 50 arranged on the same axial line as the center of rotation of the plates 14, 16 through an eccentric joint 52. The eccentric joint 52 is equipped with a connection shaft 52b eccentric to the main drive shaft 50, and the carrier 12 is rotatably connected with this connection shaft 52b at its center. An internal gear wheel 60 is arranged on a circle concentric with the main drive shaft 50 outside the carrier 12, and a portion of the carrier 12 is engaged with the internal gear wheel 60. The main drive shaft 50 is arranged in the radial direction of rotation inwardly of an outer periphery of the carrier 12 in a plan view. <P>COPYRIGHT: (C)2004,JPO |
