摘要 |
An apparatus, and particularly, a wafer carrier for polishing the face of a semiconductor wafer are provided. The wafer carrier forms a first cavity which can be pressure controlled to vary the shape of a face of a platen which contacts the wafer during polishing. A second cavity within the first cavity is provided. The second cavity can be independently pressure controlled to form a vacuum for holding the wafer against the platen surface or for forming a pressure stream to separate the wafer from the platen and/or to purge the holes in the surface of the platen. A non-contact displacement sensor capable of measuring a distance between the wafer carrier mount and the platen, may be provided. An endpoint detector capable of detecting a relative surface roughness of the wafer, to determine when the wafer has been sufficiently polished, may also be provided. A ring is peripherally located about an outer edge of the platen, and is mounted and positioned to resist lateral forces on the wafer during polishing. The ring is adjustably mounted so as to be variably and controllably vertically positioned, with respect to the wafer to help control standing waves in the polishing media and uneven polishing of the wafer surface.
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