The great interest in the study of diamond-like carbon films (a-C:H) is justified by its mechanical and tribological properties. However, the high internal stress of the film results in its difficult adhesion to the metallic substrate, which can be solved by nitrogen incorporation in the a-C:H film, allowing a formed film of lower internal stress. The objective of this work is to evaluate the influence of flow (20, 30 and 40sccm), CH 4 /Ar ratio (90/10 and 70/30) and voltage (400, 500, 600 and 700 V) in the a-C:H formation. For the best condition of the film, we studied the effect of nitrogen incorporation in the hardness and wear resistance of the a-C:H(N), modifying the nitrogen percentage in the treatment at 10% to 60% N 2 . The treatments were carried out in the Ti 6 Al 4 V substrate by DC-PECVD for two hours. For good adhesion of the films on the substrate, a silicon interlayer must be produced. The increase in the voltage above 600 V increases the I D /I G and film thickness, causing its delamination, and the gas ratio did not influence the a-C:H characteristics. The a-C:H film deposited with 30 sccm, 90/10 and 500 V was characterized as a-C:H (hard), with properties such as the hardness of 17 GPa, 30% H, 39% sp 3 and I D /I G ratio of 0.58. Since nitrogen reduced the deposition rate, the total gas flow for the production of a-C:H(N) was performed with 40 sccm. The Raman spectra of a-C:H(N) films showed changes in D band intensity and displacement in relation to the nitrogen-free film spectrum, evidencing the incorporation of nitrogen in the film. The XPS analysis showed the linear increase of the nitrogen incorporation in the a-C:H(N) film with the increase of the amount of the N 2 gas in the treatment, which caused, in general, a decrease in the amount of C-C sp 3 bonding, increasing the adhesion of the film in the substrate and not necessarily the low wear resistance of the formed film.According to Robertson [4] the DLC film that presents hydrogen concentrations between 30 and 50% receives the nomenclature of hydrogenated amorphous carbon (a-C:H), and presents lower hardness and internal stress than ta-C, facilitating the adhesion process of the film in the metallic substrates. This occurs due to sp 2 bonds formed in detriment of sp 3 bonds.The DLC films have been used in a variety of applications due to their notable properties, as protective coatings against wear and corrosion, in optical windows (optical filters), data storage hard drives, high performance automotive parts, coatings for biomedical products and electromechanical microdevices [9][10][11][12].However, as reported by Chen et al [13] and confirmed by Cemin et al [11], the high intrinsic compressive stress of the film, the high variation of the elastic coefficient, the difference in thermal expansion and the low chemical affinity between DLC and substrate difficult the adhesion process of the DLC film mainly when deposited on metallic surfaces. Thus, the use of techniques as oxide layer removal and the use of film interlayer previously to ...

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