Method and system for improving accuracy of critical dimension metrology

摘要

A method for improving accuracy of optical critical dimension measurement of a substrate is provided. A process parameter that influences the refractive index and extinction coefficient of a thin film in the substrate is identified. A refractive index and extinction coefficient across a plurality of wavelengths as a function of the process parameter is identified. During the regression modeling of the optical critical dimension measurement, the refractive index and extinction coefficient across the plurality of wavelengths is adjusted through the function via the process parameter.