摘要 |
An apparatus and method for determining the roughness of a polishing surface of a chemical mechanical polishing (CMP) pad employing a light source and associated optics for producing a light beam which impinges on the polishing surface of the polishing pad, and a light detector for detecting light emanating from the polishing surface as a result of the light beam impinging thereon. The light detector includes elements for outputting a signal representative of the light detected. In addition, there is a device for comparing the signal output by the light detector to a prescribed signal, where the prescribed signal corresponds to a signal produced by the light detector when the polishing surface of the pad has a desired roughness.
|