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We grew Ge-SbTe films on glass substrates using RF sputtering deposition. We measured the dielectric function of the Ge-doped SbTe thin films in the infrared and visible spectral region. By applying linear extrapolation to the absorption coefficient, we obtained accurate band gap energy values, which decreased with increasing Te composition. Using the Drude model, we estimated their resistivity and mean scattering time. Compared to the Hall effect parameters of carrier concentration and mobility, we estimated the effective mass of holes for the Ge-SbTe thin films.

Rotatable retarders have been developed for applications in spectroscopic, full Mueller Matrix ellipsometry in the far-IR spectral range. Several materials, such as silicon, KRS-5, and a commercial polymer plastic (TOPAS) have been utilized to achieve a fully adjustable retardation between 0° and 90°. Experimental characteristics of the rotatable retarders that utilize three- and four-bounce designs are compared with calculations. We discuss the effect of light focusing on the performance of these rotatable retarders.

Using variable-angle spectroscopic ellipsometry, we measure the pseudo-dielectric functions of as-deposited and annealed SiO2/SiOx multilayers. The SiO2(2 nm)/SiOx(2 nm) multilayers are prepared under various deposition temperatures by ion beam sputtering. Annealing at temperatures above 1100 °C leads to the formation of Si nanocrystals (nc-Si) in the SiOx layer of multilayers. Transmission electron microscopy images clearly demonstrate the existence of nc-Si. We assume a Tauc–Lorentz lineshape for the dielectric function of nc-Si, and use an effective medium approximation for SiO2/nc-Si multilayers as a mixture of nc-Si and SiO2. We successfully estimate the dielectric function of nc-Si and its volume fraction. We find that the volume fraction of nc-Si decreases after annealing, with increasing x in as-deposited SiOx layer. This result is compared to expected nc-Si volume fraction, which is estimated from the stoichiometry of SiOx.

We grew ZnO and Zn 1− x Mg x O thin films on (0001) sapphire substrate by metal-organic vapor phase epitaxy and measured the dielectric functions using variable angle spectroscopic ellipsometry. We analyzed the dielectric functions using a multi-layer model. We included non-uniform thickness of layers in the model. The dielectric functions were fitted using the Holden model dielectric function. We used anisotropic layer modeling for the ZnO thin film, whereas we adopted the approximation of isotropic layer modeling for Zn 1− x Mg x O alloys. We also discussed the Mg composition dependence of the band-gap and binding energy in Zn 1− x Mg x O alloys.