Ti-Si-C-ON films were deposited by DC reactive magnetron sputtering using different partial pressure ratio of oxygen (p O 2 ) and nitrogen (p N 2 ). Compositional analysis revealed the existence of three different growth zones for the films; (I) N/Ti = 2.1 (high atomic ratio) and low oxygen content; (II) 0.76 b N/Ti b 2.1 (intermediate atomic ratio) and (III) N/Ti ≤ 0.12 (low ratio) and high oxygen content. For high N/Ti atomic ratio (N/Ti = 2.1) the XRD pattern exhibits reflections that correspond to a mixture of two different phases: a metallic-like Ti and a fcc NaCl type structure. Its electrical resistivity presents a metallic character and, consequently, has high infrared reflectivity. For the intermediate N/Ti ratio (0.76 b N/Ti b 2.1), the films crystallize in a B1-NaCl crystal structure typical for TiC 0.2 N 0.8 . Their FTIR spectra present C-N modes, besides the TiN ones, that indicate a progressive substitution of nitrogen by carbon atoms with increasing oxygen content (and lowering N/Ti ratio). For the highest oxygen content (and lower N/Ti ratio) the presence of the Ti-O-Ti stretching mode shows the formation of highly resistive Ti-O compounds consistent with the semiconductor character of this film. Biofilm formation as well as material cytotoxicity seemed to be related with the presence of the Ti.

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a b s t r a c tDetailed structural, microstructural, biofilm formation and cytotoxicity studies were performed on Ti-Si-C-ON hard coatings prepared by DC reactive magnetron sputtering, in order to evaluate the relation among these properties. Compositional analysis showed the existence of two distinct regimens; regime I: high C/Si atomic ratio (C/Si ≥ 1.42) and intermediate N/Ti atomic ratio; regime II: low C/Si atomic ratio (C/Si ≤ 0.49) and low N/Ti atomic ratio. The structural analysis revealed that, in regime I, films crystallized in a B1-NaCl crystal structure typical of TiC 0.2 N 0.8 . In regime II, the decrease of C/Si and increase in silicon concentration led to the formation of Ti-Si-C-ON along with a reduction of grain size in the films. Atomic force microscopy observations showed that the surface morphology of these Ti-Si-C-ON films became smoother when the silicon content increased and the nitrogen content decreased, which is consistent with the formation of nanosized clusters. Concerning biological properties, it was observed that cytotoxicity could be related with the titanium concentration while biofilm formation ability was found to be related with the surface morphology of the films.

Transparent, conducting, Al-doped ZnO films have been deposited, by dc and pulsed dc magnetron sputtering, on glass and electroactive polymer (poly (vinylidene fluoride)-PVDF) substrates. Samples have been prepared at room temperature varying the argon sputtering pressure, after optimizing other processing conditions. All ZnO:Al films are polycrystalline and preferentially oriented along the [002] axis. Electrical resistivity around 3.3x10-3 Ω.cm and optical transmittance of ~85% at 550 nm have been obtained for AZOY films deposited on glass, while a resistivity of 1.7x10-2 Ω.cm and transmittance of ~70% at 550 nm have been attained in similar coatings on PVDF. One of the main parameters affecting film resistivity seems to be the roughness of the substrate.

Transparent, conducting, indium tin oxide (ITO) films have been deposited, by pulsed dc magnetron sputtering, on glass and electroactive polymer (poly (vinylidene fluoride)-PVDF) substrates. Samples have been prepared at room temperature by varying the oxygen partial pressure. Electrical resistivity around 8.4x10-4 Ω. cm has been obtained for films deposited on glass, while a resistivity of 1.7x10-3 Ω. cm has been attained in similar coatings on PVDF. Fragmentation tests were performed on PVDF substrates with thicknesses of 28 µm and 110 µm coated with 40 nm ITO layer. The coating´s fragmentation process was analyzed and the crack onset strain and cohesive strength of ITO layers were evaluated.