Polishing apparatus with dressing position setting means

A polishing apparatus which comprises:

• a polishing tool on which a polishing pad is mounted;
• and polishing target object holding means for holding a polishing target object, and which polishes a surface of the polishing target object by a relative movement of the polishing tool and the polishing target object holding means with the polishing pad being in a state of contact with the polishing target object held by the polishing target object holding means, the polishing apparatus further comprising:
• a dresser for dressing the polishing pad by bringing a rotated dressing surface thereof into contact with a surface of the polishing pad mounted on the polishing tool;
• pad shape measurement means for measuring a shape of the polishing pad mounted on the polishing tool;
• pad machining control means for, while acquiring data indicating a relationship between a dressing position defined by a distance between a rotating shaft of the polishing pad and a rotating shaft of the dresser and shape change of the polishing pad based on input of a target shape of the polishing pad and alternating repetition of dressing the polishing pad by the dresser and measurement of shape of the polishing pad by pad shape measurement means at a stage prior to commencement of a series of polishing steps for continuously polishing a plurality of the polishing target objects by the polishing tool, machining the polishing pad to the target shape while controlling the dressing position;
• and
• dressing position setting means for setting a dressing position during the polishing steps based on a processing result of the data.