Feedback controlled polishing processes

A computer program product, tangibly stored on machine-readable medium, for generating feedback for chemical mechanical polishing, the product comprising instructions operable to cause a processor to:

• receive monitoring information during a current polishing cycle in which a first polishing process is performed on a substrate that includes a metal layer and that includes multiple regions, the first polishing process clearing the metal layer from the substrate during the current polishing cycle,
• calculate clearing times for the first polishing process, each calculated clearing time corresponding to one of the multiple regions, the calculation being based on the monitoring information received during the current polishing cycle;
• detect non-uniformity in the calculated clearing times;
• generate, from the non-uniformity detected, feedback information for improving the uniformity of a clearing profile of the first polishing process;
• and
• adjust the first polishing process in a subsequent polishing cycle, the adjustment being based on the feedback information.