This article reports on interrelationships between x-ray structure, mechanical properties, coefficient of friction μ, and wear coefficient k of ∼3000 m thick nc-TiC/a-C nanocomposite films sputtered using unbalanced magnetron from a composed C/Ti target (∅=100 mm); here nc and a denotes the nanocrystalline and amorphous phase, respectively. It is shown that (1) μ and k of the nc-TiC/a-C nanocomposite film strongly depend not only on its hardness H but also on its effective Young’s modulus E∗=E/(1−ν2); here ν is the Poisson s ratio, (2) the nc-TiC/a-C nanocomposite films with C/Ti>1.5 and the ratio H3/E∗2 (characterizing the resistance of film to plastic deformation) ranging from ∼0.2 to ∼0.3 exhibit the lowest values of μ and k, and (3) μ increases with increasing load L of the testing ball. The main result of this investigation is the finding that the achievement of the lowest value E∗ at a given value of H is of key importance in the formation of films with the lowest values of coefficient of friction μ and wear coefficient k.

In this paper we report results from optical transmittance spectroscopy complemented with data on structure from XRD measurements to determine optical properties of a series of ZnTiO 3 perovskite thin films deposited on glass by reactive magnetron co-sputtering. The members of the series differ by the titanium content that was revealed as an origin of the changes not only in structure but also in dispersive optical properties. Low porosity has been discovered and calculated using the Bruggeman effective medium approximation. An apparent blue-shift of the optical band gap energies with increasing titanium content was observed. The observed band gap engineering is a good prospective for eg optoelectronic and photocatalytic applications of ZnTiO 3 .

Barium titanate (BaTiO 3 , BTO) is a perovskite class material of remarkable dielectric, ferroelectric and ferromagnetic properties. Our previous studies on optical properties of BTO thin films proved high visible transmittance and sharp absorption edge at ~ 300 nm. Therefore the usage of BTO as a UV blocker or an antireflection (AR) coating in visible region is straightforward. AR coatings are agreed to be important parts of many photonic devices, among them also of solar cells. In this paper, single layers of amorphous BTO are numerically and experimentally investigated as promising AR coatings for achieving increased light trapping in thin film silicon solar cells. Reduced reflections achieved by BTO thin films deposited using RF magnetron sputtering on a-Si:H/SiO 2 compared with pristine a-Si:H/SiO 2 system are clearly demonstrated. Antireflection effects are analyzed using simple AR systems comprising BTO.

Aluminum-doped zinc oxide (AZO) is a suitable material for use as transparent electrode. Due to its lower price it is applied in the production of silicon solar cells. However, it is difficult to obtain suitable electrical properties at low deposition temperatures. Moreover, the AZO films with low thickness exhibit significantly higher average resistivity, which limits their usability, especially if they are prepared on flexible substrates. A lot of effort is invested to replace indium tin oxide (ITO) to a much greater extent now, since Indium is rare and its price is rising, thus the preparation of lowthickness AZO films at low temperature is also subject of intense research. The presented paper summarizes the reported results, discusses the causes of the differences between ITO and AZO films, and suggests the direction of research and the potential solution that should lead to increased usability of AZO films and also possible replacement of ITO films.

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