High power pulsed magnetron sputtering is used for the growth of titanium dioxide (TiO2) films at different working pressures and orientations of the substrate with respect to the target surface. In the case of substrates oriented parallel to the target surface, the increase in the working pressure from 0.5 to 3 Pa results in the growth of crystalline TiO2 films with phase compositions ranging from rutile to anatase/rutile mixtures. When depositions are performed on substrates placed perpendicularly to the target surface, rutile films that consist of TiO2 nanocrystals embedded in an amorphous matrix are obtained at 0.5 Pa. Increase in the working pressure leads to the deposition of amorphous films. These findings are discussed in the light of the energetic bombardment provided to the growing film at the various deposition conditions.

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Optical components made of fused silica are in great demand due to the material’s exceptional properties: a broad transmission range from 185 nm to 2.5 μm, low coefficient of thermal expansion, low thermal conductivity and high radiation resistance. For the production of complex optical components in medium and large quantities, the technology of precision glass moulding is particularly suitable. Here, a glass blank is heated up to the moulding temperature and moulded into the desired shape by means of two moulding tools without any subsequent work. The production of the complex moulding tools is still costly in terms of labor and time but the efficiency of the process increases with the number of optical components made by using a pair of moulding tools. Hence, the wear of the moulding tools determines the efficiency of the process. In this paper, an experimental study and FE simulation are presented in order to investigate the wear of the glassy carbon moulding tools in moulding of fused silica. For the FE simulation, the viscoelasticity of fused silica and the friction coefficient between fused silica and glassy carbon were determined. The influence of the process parameters temperature and pressing force on the wear of moulding tools was analysed

A theoretical treatment of the deposition process in a non-reactive high power pulsed magnetron sputtering discharge is presented. This leads to the development of a semi-quantitative model that describes the deposition rate as a function of process parameters, such as the target voltage, the peak target current density, the pulse frequency and the pulse duty cycle. The effect of these parameters on the deposition rate is studied experimentally using carbon, chromium and copper targets. The implementation of the model on the experimental results enables the estimation of the relative fractions of the sputtering gas ions (Ar+) and the sputtered metal ions (M+) in the total ion flux at the target. The M+ content in the target ion current is calculated to adopt values up to ∼72% and ∼98% for the chromium and the copper targets, respectively. In contrast, the target ion current is found to consist mostly of Ar+ species in the case of the carbon target. The significantly higher fractions of M+ ions for chromium and copper are attributed to their higher ionization probability and their higher sputtering yield in comparison with carbon.

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