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ZrCN coatings were deposited by dc reactive magnetron sputtering with N 2 flows ranging from 2 to 10 sccm in order to investigate the influence of the nitrogen incorporation on structure and properties. Information about the chemical composition was obtained by glow discharge optical emission spectroscopy and Rutherford backscattering spectroscopy. The evolution of the crystal structure studied by X-ray diffraction revealed the formation of a face-centred cubic ZrCN phase for N 2 flows greater than 4 sccm. Additionally, the presence of an amorphous phase in the coatings deposited with the highest N 2 flows could be evidenced by Raman spectroscopy and X-ray photoelectron spectroscopy. This phase can act as a lubricant resulting in a low coefficient of friction as shown in the conducted ball-on-disc tests. Nanoindentation measurements showed that coatings deposited with a 6 sccm N 2 flow had the maximum hardness which also revealed the best performance in the conducted dry cutting tests.

It has been shown recently that the perovskite oxide SrVO3 is a transparent conductor with optical and electrical properties outreaching those of the most used material indium tin oxide (ITO). These properties, observed in the crystalline phase, imply the strong potential of SrVO3 for use as a lower cost alternative to ITO, but the possible integration of this perovskite oxide material in actual electronic devices is still an open question. One of the possible approaches for the integration of oxide materials is the use of amorphous thin films, allowing low thermal budgets to preserve the performances of the electronic device. Therefore, in this study, the electrical and optical properties of amorphous or poorly crystallized thin SrVO3 films are investigated.

Nowadays, with the increase of elderly population and related health problems, knee and hip joint prosthesis are being widely used worldwide. However, failure of these invasive devices occurs in a high percentage thus demanding the revision of the chirurgical procedure. Within the reasons of failure, microbial infections, either hospital or subsequently-acquired, contribute in high number to the statistics. Staphylococcus epidermidis (S. epidermidis) has emerged as one of the major nosocomial pathogens associated with these infections. Silver has a historic performance in medicine due to its potent antimicrobial activity, with a broad-spectrum on the activity of different types of microorganisms. Consequently, the main goal of this work was to produce Ag-ZrCN coatings with antimicrobial activity, for the surface modification of hip prostheses. Thin films of ZrCN with several silver concentrations were deposited onto stainless steel 316 L, by DC reactive magnetron sputtering, using two targets, Zr and Zr with silver pellets (Zr+Ag target), in an atmosphere containing Ar, C2H2 and N2. The antimicrobial activity of the modified surfaces was tested against S. epidermidis and the influence of an activation step of silver was assessed by testing samples after immersion in a 5% (w/v) NaClO solution for 5 min. The activation procedure revealed to be essential for the antimicrobial activity, as observed by the presence of an inhibition halo on the surface with 11 at.% of Ag. The morphology analysis of the surface before and after the activation procedure revealed differences in silver distribution indicating segregation/diffusion of the metallic element to the film's surface. Thus, the results indicate that the silver activation step is responsible for an antimicrobial effect of the coatings, due to silver oxidation and silver ion release.

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Ag-TiCN coatings were deposited by dc reactive magnetron sputtering and their structural and morphological properties were evaluated. Compositional analysis showed the existence of Ag-TiCN coatings with different Ag/Ti atomic ratios (ranging from 0 to 1.49). The structural and morphological properties are well correlated with the evolution of Ag/Ti atomic ratio. For the samples with low Ag/Ti atomic ratio (below 0.20) the coatings crystallize in a B1-NaCl crystal structure typical of TiC 0.3 N 0.7. The increase in Ag/Ti atomic ratio promoted the formation of Ag crystalline phases as well as amorphous CN x phases detected in both x-ray photoelectron spectroscopy and Raman spectroscopy analysis. Simultaneously to the formation of Ag crystalline phases and amorphous carbon-based phases, a decrease in TiC 0.3 N 0.7 grain size was observed as well as the densification of coatings.

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