Spectroscopic-ellipsometry and thermoreflectance spectra of sputter-deposited InSb films

Spectroscopic-ellipsometry (SE) and thermoreflectance (TR) spectra of InSb films sputter-deposited on sapphire substrates are reported. Measurements are made on the same crystal in the 1.5-5.5-eV photon energy range at room temperature. These data are analyzed on the basis of a simplified model of the interband transitions. Results are in satisfactory agreement with the experimental data over the entire range of photon energies. The finding definitely links the temperature-induced change in the dielectric function (TR) to the first derivative of the dielectric function (SE).