Spectral polarimetry technique as a complementary tool to ellipsometry of dielectric films

Ellipsometry is a highly sensitive optical technique for coating characterization but usually presents multiple solutions in many cases. To prevent these, a method with addition of a spectral polarimetric technique is proposed. An initial film dispersion curve, independently of its physical thickness, is then provided using the same setup as spectral ellipsometry and at the same sample position, which later is used for thickness determination and dispersion refinement with increase of reliability of results. Characterization of thin TiO2 films with one and two ellipsometric solutions is shown to corroborate the validity of the proposed method.