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New multifunctional materials based on well-established materials to which functional properties are added, such as antibacterial performance, have become a relevant research topic, in order to meet the requirements of today's technological advances. This paper reports the results of a detailed structural and chemical characterization study of ZrCN-Ag coatings produced by reactive magnetron sputtering, as well as the release of silver after immersion in a simulated body fluid (Hank's balanced salt solution), which mimic the material behaviour within the human body. The chemical composition was evaluated by electron probe microanalysis, x-ray photoelectron spectroscopy and Rutherford backscattering spectroscopy, whereas the structure was assessed by Raman spectroscopy and x-ray diffraction. The material exhibits a homogeneous distribution of the elements throughout the films, with a (C + N)/Zr ratio of around 1.3 and 15 at% of silver. A mixture of amorphous (a-C and CNx) and crystalline phases (ZrCN) was identified. In addition, the silver was detected to be released in less than 0.7% of the total silver in the films, occurring during the first two hours of immersion; no further release was evidenced after this period of time. [ABSTRACT FROM AUTHOR]

This work reports the development of non-hydrogenated magnetron-sputtered silicon and silicon-oxygen containing amorphous carbon coatings with increasing silicon and oxygen contents respectively. The Si content of a-C:Si coatings increases linearly with the increase of the power applied to the Si target up to 24 at.%, while to the system a-C:Si:O the O content increases with the increase of the oxygen flow to a maximum of 27 at.%. The hardness of the a-C:Si coatings shows two distinct trends with the increase of the Si content, a decrease of hardness for Si contents lower than 10 at.% and an increment above this value are observed. The coatings of the system a-C:Si:O present a decrease of hardness and Young modulus with the increase of the O content. The tribological performance of the coatings is significantly improved by doping the amorphous carbon coatings with silicon and oxygen with a reduction of the friction from 0.17 for the undoped carbon coating to 0.034 for the coating of the system a-C:Si:O with the highest O content. [ABSTRACT FROM AUTHOR]

Abstract: Ti–Si–C–ON films were deposited by DC reactive magnetron sputtering and their chemical properties, biofilm formation and toxicity were characterized. Based on the films composition three different growth regimes were identified on the films; (I) N/Ti = 2.11 (high atomic ratio) and low oxygen content; (II) 0.77 ≤ N/Ti ≤ 1.86 (intermediate atomic ratio) and (III) N/Ti ≤ 0.12 (low ratio) and high oxygen content. The phase composition varied from mainly TiN on regime I to TiCN on regime 2 and titanium oxides on regime III. Taking into account the results of biological characterization (biofilm formation and cytotoxicity), it was possible to conclude that samples with a high TiN content (regime I) presented more favorable biocompatibility, since it was less prone to microbial colonization and also displayed a low cytotoxicity. [Copyright &y& Elsevier]

Abstract: Detailed 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 TiC0.2N0.8. 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. [Copyright &y& Elsevier]

Abstract: Cr–O–Al thin film mixed oxides grown on Si (100) substrates by reactive magnetron sputtering using different target compositions from 90% Cr (10% Al) to 10% Cr (90% Al) and oxygen fluxes in the range from 0 to 15sccm have been investigated using ex situ XPS, XPS depth profiles and ARXPS. The chemical information obtained with XPS as well as the observed chemical shift of the Cr 2p, Al 2s and O 1s bands points to the formation of mixed substitutional Me2O3 oxides (Me=Al+Cr) instead of the formation of single oxide phases. Compositions and stoichiometries obtained from concentration depth profile measurements (CDP) simultaneously using XPS and Ar+ bombardment confirm the formation of such a type of substitutional mixed oxides. ARXPS allows ruling out oxygen preferential sputtering during Ar+ bombardment. Finally, it is shown that the optical properties of the films like their refractive index can be controlled through their chemical composition. [Copyright &y& Elsevier]

Abstract: The development of mixed-oxide thin films allows obtaining materials with better properties than those of the different binary oxides, which makes them suitable for a great number of applications in different fields, such as tribology, optics or microelectronics. In this paper we investigate the deposition of mixed chromium and silicon oxides deposited by reactive magnetron sputtering with a view to use them as optical coatings with an adjustable refractive index. These films have been characterized by means of Rutherford backscattering spectrometry, Auger electron spectroscopy, X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy and spectroscopic ellipsometry so as to determine how the deposition conditions influence the characteristics of the material. We have found that the deposition parameter whose influence determines the properties of the films to a greater extent is the amount of oxygen in the reactive sputtering gas. [Copyright &y& Elsevier]

Abstract: ZrCN coatings were deposited by dc reactive magnetron sputtering with N2 flows ranging from 2 to 10sccm 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 N2 flows greater than 4sccm. Additionally, the presence of an amorphous phase in the coatings deposited with the highest N2 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 6sccm N2 flow had the maximum hardness which also revealed the best performance in the conducted dry cutting tests. [ABSTRACT FROM AUTHOR]