Research on carbon nitride has received considerable attention since beta -C3N4 offers high technological potential for protective, wear, and optical applications. Deposition of carbon nitride by various techniques has mostly resulted in nitrogen deficient amorphous CN, films. In this research, reactive magnetron sputtering with and without the assistance of an electron cyclotron resonance (ECR) source was used to deposit CN, thin films at ambient temperature. The process variables include power level, nitrogen partial pressure, and substrate bias. X-Ray photoelectron spectroscopy and Auger analysis were used to determine the composition and chemical bonding of the films. Ball-on-disc experiments were performed between 440C stainless steel balls and CNx-coated 440C substrates at 0.1 m/s sliding velocity and 1 N load. The effects of process variables and interface modification on friction and wear rate were examined. Mechanical properties including hardness, modulus, and elastic response were obtained from nanoindentation. CN, films with hardness in the range of 12-16 GPa demonstrated better wear performance than the hardest diamond-like carbon (24 GPa) deposited by the same technique. ECR assisted magnetron sputtering provided films with the lowest wear rates.