BROAD-SPECTRUM OPTICAL-PHASE RETARDER USING 3 METALLIC MIRRORS FOR NORMAL AND BREWSTER ANGLE OF INCIDENCE ELLIPSOMETRY

An optical phase retarder for the photon energy range of 1.5-5.5 eV (8 25-225 nm) is described. The use of metallic mirrors yields good trans mission in the entire energy range and the smooth energy dependence of the phase shift is convenient for in situ spectroscopic ellipsometric applications. The optical properties of the retarder are in good agre ement with its expected values. The retarder has proved to be a valuab le improvement in ellipsometry measurements and enables the use of a c onventional rotating polariser ellipsometer for normal incidence measu rements. (C) 1996 American Institute of Physics.