| 摘要 |
A polishing machine for polishing a single side (e.g. a circuit side) of a workpiece (e.g. a semiconductor wafer) includes two platens. A first platen can be a workpiece-holding platen having slots or other structure for holding wafers or other workpieces. The second platen is a polishing platen and is covered with a polishing pad or other material used for polishing, e.g. glass or metal polishing. The two platens have laterally spaced axes of rotation such that, from a top view, the right side of one platen overlaps the left side of the other platen or vice versa. The two platens are both rotated at the same angular velocity i.e. at the same revolutions per minute (RPM) and both clockwise or both counterclockwise, and the two platens overlap such that the differences in velocity (i.e., relative velocity) between overlapping points on the two platens across a workpiece held on the first platen is constant. A second embodiment of the polishing machine uses one or more polishing rollers, instead of the polishing platen described above. In the second embodiment as well, a uniform relative velocity is obtained at overlapping points on the two platens across the workpiece when the angular velocity of the workpiece-holding platen is equal to the angular velocity of the polishing roller about a lateral axis perpendicular to the longitudinal axis of the polishing roller. The polishing roller is simultaneously rotated about the longitudinal axis (which is perpendicular to the lateral axis) to increase or decrease the uniform relative velocity with which the workpiece is polished.
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