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ZrNx (x = 0.67&ndash, 1.38) films were fabricated through direct current magnetron sputtering by a varying nitrogen flow ratio [N2/(Ar + N2)] ranging from 0.4 to 1.0. The structural variation, bonding characteristics, and mechanical properties of the ZrNx films were investigated. The results indicated that the structure of the films prepared using a nitrogen flow ratio of 0.4 exhibited a crystalline cubic ZrN phase. The phase gradually changed to a mixture of crystalline ZrN and orthorhombic Zr3N4 followed by a Zr3N4 dominant phase as the N2 flow ratio increased up to &gt, 0.5 and &gt, 0.85, respectively. The bonding characteristics of the ZrNx films comprising Zr&ndash, N bonds of ZrN and Zr3N4 compounds were examined by X-ray photoelectron spectroscopy and were well correlated with the structural variation. With the formation of orthorhombic Zr3N4, the nanoindentation hardness and Young&rsquo, s modulus levels of the ZrNx (x = 0.92&ndash, 1.38) films exhibited insignificant variations ranging from 18.3 to 19.0 GPa and from 210 to 234 GPa, respectively.

Non-stoichiometric NbxNy coatings, produced in a reactive sputtering process, were analyzed on the basis of their chemical composition (specifically, nitrogen concentration) and its relationship with electrical conductivity. The chemical composition and bonding configuration were examined using X-ray photoelectron spectroscopy (XPS), revealing Nb&ndash, N bonds. The stoichiometry variation dependence on the N2 flow was also analyzed, using Auger electron spectroscopy (AES). Without exposing the samples to air, a normal behavior was observed, meaning that the nitrogen concentration in the coatings increased, with an increase in N2 flow. The electrical properties were evaluated and their relationship with nitrogen content in the films was analyzed. The highest conductivity value for all studied samples was observed for the sub-stoichiometric film, NbN0.32, which also exhibited a positive Hall coefficient. It indicated that the conduction was mainly dominated by hole-type carriers. High conductivity at lower nitrogen content was attributed to the fact that, at a low concentration of nitrogen, the effect of impurities, acting as dispersion points for electrons, was lower, increasing the relaxation time. As the main conclusion, the Ar/N2 flow ratio strongly influenced the coatings of stoichiometry and then, this stoichiometry affected, to a great extent, the electrical conduction and the Hall coefficient of the coatings.

MoSN/MoS2 multilayer films were deposited by a sputtering MoS2 target in alternate Ar and Ar/N2 mixed atmospheres with different nitrogen flow rates. The influence of nitrogen flow rates on the microstructure, mechanical and tribological properties of the prepared films were investigated. The multilayer film exhibited the preferred orientation of (002) plane for MoS2 sublayers and amorphous structure for MoSN sublayers. Introducing N2 into the source gas resulted in a much more compact structure for multilayer films due to the suppression of columnar growth of MoS2 film. With the increase of the nitrogen flow rate, the hardness of the multilayer film firstly increased from 2.3 to 10.5 GPa as the nitrogen flow rate increased from 4 to 10 sccm and then turned downwards to 6.5 GPa at 20 sccm. MoSN/MoS2 film deposited with an optimized microstructure exhibited low friction coefficients below 0.03 and a wear life higher than 1.8&times, 105 revolutions in vacuum. Meanwhile, the optimized film showed an ultralow friction coefficient of 0.004~0.01 and wear rate of 4.7 &times, 10&minus, 7 mm3/N&middot, m in an ultrahigh vacuum. Both the enhanced hardness by N-doping and sustainable formed MoS2 tribofilm contributed to the improved tribological property of MoSN/MoS2 multilayer film.

The reactive gas flow ratio and substrate bias voltage are crucial sputtering parameters for fabricating transition metal nitride films. In this study, W&ndash, N films were prepared using sputtering with nitrogen flow ratios (f) of 0.1&ndash, 0.5. W&ndash, N and W&ndash, Si&ndash, N films were then prepared using an f level of 0.4 and substrate bias varying from 0 to &minus, 150 V by using sputtering and co-sputtering, respectively. The variations in phase structures, bonding characteristics, mechanical properties, and wear resistance of the W&ndash, N films were investigated. The W&ndash, N films prepared with nitrogen flow ratios of 0.1&ndash, 0.2, 0.3, and 0.4&ndash, 0.5 displayed crystalline W, amorphous W&ndash, N, and crystalline W2N, respectively. The W&ndash, N films prepared using a nitrogen flow ratio of 0.4 and substrate bias voltages of &minus, 50 and &minus, 100 V exhibited favorable mechanical properties and high wear resistance. The mechanical properties of the amorphous W&ndash, N films were not related to the magnitude of the substrate bias.

Zr&ndash, Si&ndash, N films were fabricated through the co-deposition of high-power impulse magnetron sputtering (HiPIMS) and radio-frequency magnetron sputtering (RFMS). The mechanical properties of the films fabricated using various nitrogen flow rates and radio-frequency powers were investigated. The HiPIMS/RFMS co-sputtered Zr&ndash, N films were under-stoichiometric. These films with Si content of less than 9 at.%, and N content of less than 43 at.% displayed a face-centered cubic structure. The films&rsquo, hardness and Young&rsquo, s modulus exhibited an evident relationship to their compressive residual stresses. The films with 2&ndash, 6 at.% Si exhibited high hardness of 33&ndash, 34 GPa and high Young&rsquo, s moduli of 346&ndash, 373 GPa, which was accompanied with compressive residual stresses from &minus, 4.4 to &minus, 5.0 GPa.