A method of determining a thickness at a thickness position of a
conductive film on a substrate with a center zone and an edge zone is
disclosed. The method includes providing a set of thickness correlation
curves at a set of sensor position radii from a center of the substrate
to a position where a sensitivity of an eddy current sensor to the edge
zone is greater than zero. The method also includes measuring a set of
eddy current responses at a sensor position of the set of sensor position
radii. The method further includes correlating the set of eddy current
responses to the thickness at the thickness position.