A METHOD OF ASSESSING A MODEL OF A SUBSTRATE AN INSPECTION APPARATUS AND A LITHOGRAPHIC APPARATUS

摘要

A method for evaluating a model of a substrate is presented. A scatterometry measurement is performed using radiation at the first wavelength. Thereafter, the wavelength of the radiation is changed and an additional scatterometry measurement is performed. If the scatterometry measurements are consistent across a range of wavelengths, the model is sufficiently accurate. However, if the scatterometry measurements change as the wavelength changes, the model of the substrate is not sufficiently accurate.