Applied Materials, Inc.
PRESSURE SIGNALS DURING MOTOR TORQUE MONITORING TO PROVIDE SPATIAL RESOLUTION

Abstract:

A method of polishing includes holding a substrate with a carrier head against a polishing surface of a polishing pad, generating relative motion between the substrate and polishing pad, applying a first pressure modulated by a first modulation function to a first region of the substrate, applying a second pressure modulated by a second modulation function that is orthogonal to the first modulation function to a second region of the substrate, during polishing of the substrate monitoring the substrate with an in-situ friction monitoring system to generate a sequence of measured values, and determining a relative contribution to the sequence of measured value from the first region and second region based on distinguishing the first frequency from the second frequency.