| Abstract: | Multilayer dielectric coatings deposited by e-beam evaporation have been characterised by the phase modulated spectroscopic ellipsometer (PMSE). Measurements have been done on various multilayer thin films devices e.g., high reflectivity mirror, narrow band filter, beam combiner, beam splitter, etc. consisting of several bilayers of TiO2/SiO2. Results have been shown here for the first two samples. The measured Ellipsometry spectra are fitted with theoretical spectra generated assuming appropriate models regarding the sample structures. Optical constants of the substrates and the SiO2 films have been supplied and trial dispersion relations have been used for the optical constants of the TiO2 layers. The fittings have been done by minimising the squared difference (χ2) between the measured and calculated values of the ellipsometric parameters (ψ and Δ) and accurate information have been derived regarding the thickness and refractive indices of the different layers. |
