Optical characterization of nonabsorbing and weakly absorbing thin films with the wavelengths related to extrema in spectral reflectances

In this contribution a new efficient modification of a method that enables us to perform the optical characterization of nonabsorbing and weakly absor bing thin films without using the absolute values of the reflectances measu red is presented. Namely, this modification is based on determining the val ues of the wavelengths corresponding to touching the spectral dependences o f the reflectances of the studied films measured for several angles of inci dence with the envelopes of maxima and minima of these spectral dependences . By means of combining the explicit formulas containing the wavelengths me ntioned and the suitable iteration procedure one can evaluate the values of the thicknesses and spectral dependences of the refractive indices of the films analyzed in reliable and precise ways. (C) 2001 Optical Society of Am erica.