The effect of annealing temperature on the structural and optical properties of sputtered niobium–oxide films has been investigated. The temperature dependence of structure, density, and optical constants has been studied by Rutherford backscattering, x-ray diffraction, x-ray reflection, optical spectroscopy, and variable angle spectroscopic ellipsometry techniques. Rutherford backscattering measurements show no variation in the stoichiometry of the films upon annealing of amorphous Nb2O5 films, while amorphous NbO is oxidized to Nb2O5. X-ray diffraction studies show that as-deposited films are amorphous and only crystallize at around 500 °C. X-ray reflectivity studies reveal a continuous increase of film density with increasing annealing temperature. Optical spectroscopy and spectroscopic ellipsometry confirm that the refractive index n and the band gap Eg increase upon increasing annealing temperature. The variation of the refractive index with density of the niobium–oxide films is observed to follow the Clausius–Mossotti relation and the molecular electronic polarizability has been deduced from the straight line fit of Lorentz–Lorentz law.

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Direct current magnetron sputtered zirconium oxynitride films show an improvement in both deposition rate and physical properties compared to zirconium oxide. Here we seek to understand these beneficial effects and report on the film composition and crystallographic structure. Based on a thermochemical description together with a modeling of formation kinetics we propose a film formation mechanism, which explains many of the observations. Rutherford backscattering spectroscopy (RBS) shows early nitrogen incorporation at 64% N 2 flow in disagreement with the predictions of thermochemistry. The stoichiometry is only successfully simulated with the use of an expanded Berg-Larsson model with a low replacement coefficient of about 0.1 of nitrogen by oxygen after metal-nitrogen bond formation. The deviation from complete replacement as predicted by thermodynamics illustrates the importance of kinetics in film formation. The model further successfully predicts the variation of the mass deposition rate. The X-ray diffraction analyses suggest that, within the crystalline phase, nitrogen atoms occupy oxygen sites, resulting in an unchanged zirconium oxide structure.

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The thermal stability of different lead oxide films prepared by reactive dc magnetron sputtering from a Pb target has been investigated. The temperature dependence of composition as well as structural and optical properties have been studied by Rutherford backscattering spectroscopy (RBS), X‐ray diffraction (XRD) and variable‐angle spectroscopic ellipsometry (VASE). Both XRD and RBS experiments confirm that different kinds of lead oxides are formed upon increasing the oxygen flow. Upon annealing at 500 °C, all samples form orthorhombic PbO. VASE studies show that the refractive index n and the band gap energy Eg increase with increasing annealing temperature. For films annealed at 500 °C, n is approximately 2.7 at 650 nm and a band gap energy of 2.8 eV is obtained, which corresponds to the value for bulk PbO. The stoichiometric changes observed by XRD on increasing the annealing temperature are discussed and supported by thermodynamics arguments.