POSSIBILITIES AND LIMITATIONS OF ELLIPSOMETRY

The difficulties in uniquely interpreting optical experiments arise fr om the influence of the sample's surface, spatial dispersion and optic al anisotropy as well as depolarization. The possibilities of ellipsom etry to resolve some of these difficulties are discussed. The most sen sitive ellipsometric arrangement with the simultaneous variation of th e angle of incidence and the polarization of the incident light is pre sented 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.