POSSIBILITIES AND LIMITATIONS OF ELLIPSOMETRY

The difficulties in uniquely interpreting optical experiments arise from the influence of the sample's surface, spatial dispersion and optical anisotropy as well as depolarization. The possibilities of ellipsometry to resolve some of these difficulties are discussed. The most sensitive ellipsometric arrangement with the simultaneous variation of the angle of incidence and the polarization of the incident light is presented to overcome some of the above objections. The model dependence of the final interpretation of undisputable experimental results will be demonstrated for the interband transition in Al near 1.5 eV.