| 摘要 |
PURPOSE:To obtain correction of flatness of a surface plate without removing it for reduced cost and high precision flattening in a one side polishing machine for a wafer or the like by exchangeably providing a means for correcting flatness of the surface plate. CONSTITUTION:A wafer P is attached through vacuum suction to the suction surface of a head 21 of a holding mechanism 12, and rotated by a rotary shaft 16 and swingingly turned by a rotary shaft 11 to be pressed for polishing against an abrasive cloth 6 rotating in the same way. In order to correct the flatness of the surface plate 5, the applied abrasive cloth 6 is first stripped off and a chuck plate 24 of the head 21 is removed, and a correction plate including diamond pellets adhered to a plate is attached in its place. Then, polishing is performed in the same way, with water containing 1-2% of water soluble abrasive supplied. When the head 21 and the surface plate 5 are rotated in the same direction, the surface plate is finished in such a way that the central position is recessed; on the contrary, when they are rotated in the opposite directions, it is finished in such a way that the central portion is raised. Thus, ready correction possible, so that a work having a high precision flatness can be obtained at a low machining cost. |
