| 摘要 |
PROBLEM TO BE SOLVED: To uniformly lap a wafer at both sides under stable conditions by using the frictional force of ring surface plate for the self-rotation of a wafer to reduce load on a wafer rotation supporting mechanism. SOLUTION: Ring surface plate 13, 23 with lapping faces 14, 24 having outer diameters almost equal to the radius of a disc work W are opposed to the both sides of the work W and thrusted thereto to rotate the work W with a driving roller 31 contacting the edge of the work W, and the ring surface plate 13, 23 are reversely rotated at different rotating speeds to grant rotating torque resulting from a rotting speed difference to the work W for lapping the work W at both sides while supplying abrasive grain suspended slurry A to the work W via the cavities of the ring surface plate 13, 23. The ring surface plate 13, 23 may be rotated in the same direction at the same or different rotating speed(s). As rotating torque is given to the work W by the ring surface plate 13, 23, the load of the driving roller 31 is less required. |
