Correlation between wear-resistance and chemical structure of CNx films synthesized by shielded arc ion plating

Amorphous carbon nitride (a-CNx) thin films have been synthesized by shielded arc ion plating under various deposition conditions. Nanohardness and wear resistance of the films were evaluated with a nanoindenter interfaced with an atomic force microscope. The chemical structures of the synthesized a-CNx thin films were studied by Fourier transformed infrared, X-ray photoelectron and Raman spectroscopies. The nitrogen concentration of the films decreased with the increase in negative substrate bias (−Vb). All of the films prepared with applying substrate bias voltage showed wear resistive properties. The proper −Vb and incorporation of nitrogen content in the film lead to cross-linking between graphite-like layers which improve nanohardness and wear resistance of a-CNx.