| 摘要 |
PURPOSE:To prevent the droop on the perephery of the polished surface or the occurrence of projections on its edges by providing a guard ring by which the base board of a semiconductor to be processed can be vertically moved along the inner face, and carrying out polishing while maintaining the difference in height between the surface of said ring and the surface being polished at a certain value. CONSTITUTION:When the surface Ssi to be polished is polished with a polishing pad 23 rotated and a polishing liquid being poured onto the surface of a polishing cloth 25 from a polishing liquid inlet port 28, Si surface Ssi to be polished is always projected beyond the bottom face Sg of a guard ring 22, at the time of a thick silicon base board 21 being polished or even when the base board 21 is converted to a thin Si board 21 after polishing operation has advanced, and the difference DELTAH in the height between Sg and Ssi is maintained constant. Therefore, a projection is prevented from occurring on the edge parts of Ssi surface to be polished, which, thereby, can be polished smoothly at a high speed, improving the yield of the semiconductor production. |
