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The deposition of optical functional coatings with large rates yet also high refractive index and excellent transparency over a wide spectral range is of paramount importance for many applications. In this study we will demonstrate that TiO x N y films can meet these requirements. The films were deposited by reactive dc magnetron sputtering from a metallic titanium target. The sputtering atmosphere consisted of both Ar as well as oxygen and nitrogen. The starting oxygen partial pressure was 1.14 × 10 -1 Pa which corresponds to the oxidic mode of the Ti target. Then oxygen was being replaced stepwise by nitrogen. Even for high nitrogen partial pressures, only a very small amount of nitrogen incorporation in the films was observed by Rutherford Backscattering Spectroscopy and Secondary Neutral Mass Spectroscopy. This result was compared with simulations based upon thermodynamics, which however showed a significant deviation from experiment that could be explained incorporating kinetic aspects. X-ray reflectometry showed that the density and the deposition rate increase with increasing nitrogen partial pressure. X-ray diffraction revealed that the amount of incorporated oxygen tailors the crystal structure of the TiO x N y films. The optical properties were measured using optical spectroscopy and spectroscopic ellipsometry. The optical band gap was found to decrease from 3.29 to 2.11 eV with increasing nitrogen content in the sputtering gas, while the refractive index was found to increase by 15%. The detected intrinsic stresses in TiO x N y were compressive and had values similar to titanium oxide.

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Thin films of ZnS : Cu nanoparticles were prepared by electron beam evaporation on glass substrates. The Cu content was varied from 0 to 9 at%. XRD examination of the as-prepared films revealed the presence of polycrystalline hexagonal ZnS with preferred orientation depending on the Cu content. As annealing was carried out, grain growth was observed and a new orthorhombic copper sulfate phase emerged. The photocatalytic behaviour of ZnS : Cu was mainly evaluated by measuring the decomposition of methylene blue. The photocatalytic activities were found to decrease with increasing Cu content as well as with increasing annealing temperature. The optical transmittance and reflectance measurements were performed using a spectrophotometer. The spectral transmittance was decreased and the band gap energy was shifted from 3.45 to 3.20 eV with increasing Cu content. The refractive index was determined from transmittance using the Swanepoel method. The refractive index was found to depend on Cu content as well as annealing temperature. A strong decrease in room temperature resistivity was obtained with increasing Cu content. The obtained results are interesting and may find applications in photodegradation of pollutants and future display devices.