Structure and mechanical properties of nickel/carbon nanocomposite films formed by microwave plasma-assisted deposition technique from argon–acetylene gas mixture

The structure and mechanical properties of nickel/hydrogenated amorphous carbon (Ni/a-C:H) films formed by microwave plasma-assisted deposition technique were investigated as a function of the carbon content using various methods: Rutherford backscattering spectroscopy (RBS), Raman spectroscopy and tribometry. The size of carbon clusters determined by Raman spectroscopy in Ni/a-C:H films deposited in gas mixtures containing 40 and 60% of C2H2, and in nickel free a-C:H films was 1 and 4 nm, respectively. However, the amorphous Ni/a-C:H films deposited from a gas mixture containing 60% of C2H2 exhibited the lowest friction coefficient (∼ 0.04), at the same time the nanohardness of these films was ∼ 7 GPa.