*3.3. Spectrophotometric Characterization*

The transmittance (*T*) and reflectance (*R*) of all samples were measured in the spectral range of 320–2000 nm at near-normal incidence as well as at an incidence angle of 60◦ (in s- and p-polarization) in a Perkin Elmer Lambda 900 scanning spectrophotometer using the VN measurement technique [29]. From these spectra, film thickness *d* as well as optical constants *n* and *k* were obtained as a result of spectra fits in terms of Equation (2) (using a Matlab environment). In all spectra fits, the number of individual Lorentzian oscillators *M* in Equation (2) was set to *M* = 10, 000, which has been proven to model a smooth function [16].
