Patent ID: 7450232

Claim:
An optical metrology system, comprising: a processing module; and a generic interface connected to the processing module, wherein the generic interface is configured to provide a measured diffraction signal to the processing module using a standard set of signal parameters comprising: a reflectance parameter that characterizes the change in intensity of light when reflected on a structure; a first polarization parameter that characterizes the difference between the square of the absolute value of complex reflection coefficients and is an average over depolarization effects and normalized to the reflectance parameter; a second polarization parameter that characterizes an imaginary component of an interference of the complex reflection coefficients and is an average over the depolarization effects, and normalized to the reflectance parameter; and a third polarization parameter that characterizes a real component of an interference of the complex reflection coefficients and is an average over the depolarization effects, and normalized to the reflectance parameter.