Patent ID: 7242185

Claim:
A method of determining a thickness at a thickness position of a conductive film on a substrate, the method comprising: measuring a set of eddy current response values at a plurality of sensor position radii on a set of calibration conductive films on a set of calibration substrates; measuring, using one or more processes that are independent of eddy current measurement, a set of thickness values at a plurality of measurement points for said set of calibration conductive films on said set of calibration substrates; correlating said set of eddy current response values with said set of thickness values for one or more measurement points among said plurality of measurement points to produce one or more correlations, said one or more measurement points including said thickness position; measuring at least one eddy current response value at said thickness position of said conductive film; and determining, using said at least one eddy current responses value and at least one of said one or more correlations, said thickness at said thickness position of said conductive film.