[en] This paper reports the improved nanomechanical properties of as grown and nitrogen incorporated tetrahedral amorphous carbon (ta-C, ta-C: N) films deposited by S-bend filtered cathodic vacuum arc (FCVA) technique using nanoindentation. The effect of varying amount of nitrogen incorporation on the nanomechanical properties of ta-C films deposited at a high substrate bias of -300 V at ultra low load of 1.4 mN has been studied. It has been found that the nitrogenation has improved the mechanical properties of ta-C films. The hardness H of 27.8 GPa with improvement of ∼30 % and plastic index parameter (ratio of H to elastic modulus E) (H/E) of 0.091 with improvement of ∼ 25 % has been obtained for ta-C: N films deposited at a nitrogen partial pressure of 1.9×10^-2 Pa. Improved H and H/E of ta-C: N films may be due to the better ionization and incorporation of nitrogen in a carbon matrix at the high negative substrate bias used in the deposition of FCVA technique. (author)