Nitrogenated tetrahedral amorphous carbon (ta-C:N) films having nitrogen content from 0 to 10.3 at.%, have been produced by a double bend off-plane filtered cathodic vacuum arc system. X-ray photoelectron and Raman spectroscopies have been applied to study the effect of nitrogen in the bonding structure in the films. Deconvolution of the XPS spectra revealed a decrease in the amount of sp3-bonded carbon in the ta-C:N films. A comparative study between the Raman parameters at 514 and at 633 nm excitation wavelength was presented. Nitrogen (N) incorporation led to a lower G peak position and higher ID/IG ratios, indicating the development of larger sp2 domains. Q (−ve) parameter (which measures the skewness of G line) increased sharply with the increased of N content in the films. The hardness of the films was evaluated by nanoindentation.Copyright Elsevier 2004