Wear-resistant thin films of amorphous carbon nitride prepared by shieldedare ion plating

Amorphous carbon nitride (a-C:N) thin films were synthesized by means of sh ielded are ion plating using a graphite target and pure nitrogen gas. The m echanical properties and chemical structures of these a-C:N films were stud ied through nanoindentation and X-ray photoelectron Spectroscopic analysis. Nanohardness of the a-C:N film prepared at a substrate bias voltage of 0 V was approximate to 10 GPa. It was increased to 13-14 GPa when the substrat e was biased negatively in the range of - 100 to - 500 V. The a-C:N film pr epared at a bias of -300 V was particularly wear-resistant such that the fi lm did not wear at all when rubbed with a diamond tip at a contact force of 20 mu N. This highly wear-resistant a-C:N film was found to contain almost equal amounts of two C-N phases: beta-C3N4-like and graphitelike phases.