Thin film optical measurement system and method with calibrating ellipsometer

摘要

An optical measurement system, including a reference ellipsometer and a non-contact optical measurement device, evaluates a sample having at least a partially known composition. The reference ellipsometer includes a light generator to generate a beam of quasi-monochromatic light of known wavelength and polarization, directed at a non-normal angle of incidence to interact with the sample. An analyzer creates interference between S and P polarized components of the reflected beam, the intensity of which is measured by a detector. A processor determines the polarization state using the detected intensity, and determines an optical property of the sample based upon the determined polarization state, the known wavelength, and the composition. The processor calibrates the optical measurement device, used to measure an optical parameter of the sample, by comparing the measured optical parameter from the optical measurement device to the determined optical property from the reference ellipsometer.