EXTENSION OF ROTATING-ANALYZER ELLIPSOMETRY TO GENERALIZED ELLIPSOMETRY - DETERMINATION OF THE DIELECTRIC FUNCTION TENSOR FROM UNIAXIAL TIO2

For what is the first time, to our knowledge, we report on the extensi on of spectroscopic rotating-analyzer ellipsometry to generalized elli psometry to define and to determine three essentially normalized eleme nts of the optical Jones matrix J [R. M. A. Azzam and N. M. Bashara, J . Opt. Sec. Am. 62, 1521 (1972)]. These elements are measured in refle ction over the spectral range of 3.5-4.5 eV on different surface orien tations of uniaxial TiO2 cut from the same bulk crystal. With a wavele ngth-by-wavelength regression and a 4 x 4 generalized matrix algebra, both refractive and absorption indices for the ordinary and the extrao rdinary waves, n(o), k(o), n(e), and k(e), are determined. The inclina tions and the azimuths of the optic axes with respect to the sample no rmal and plane of incidence were determined as well. The latter are co nfirmed by x-ray diffraction and polarization microscopy. Hence the sp ectrally dependent dielectric function tensor in laboratory coordinate s is obtained. Very good agreement between measured and calculated dat a for the normalized Jones elements for the respective sample orientat ions and positions are presented. This technique may become an importa nt tool for investigating layered systems with nonscalar dielectric su sceptibilities. (C) 1996 Optical Society of America