Tribological properties of a-C : N and a-C films prepared by shielded arc ion plating

Amorphous carbon nitride (a-C:N) and amorphous carbon (a-C) thin films that rarely contained hydrogen were synthesized on Si(100) wafers by means of shielded are ion plating. Nanomechanical properties of these films were studied in relation to substrate bias voltage. The a-C film prepared at a DC bias voltage of 100 V showed a maximal hardness of 35 GPa, whereas the film deposited at - 500 V had a minimal hardness of 7 GPa. Wear resistance was excellent for films with hardness greater than 20 GPa when rubbed with a diamond tip at a contact force of 20 muN. Hardness of the a-C : N films, remained in the range of 10-14 GPa, independent of the bias voltage. However, the wear resistance of the a-C :N films was much better than that of the hard a-C films. In particular, the a-C : N film prepared at - 300 V was so wear resistant that the film did not wear at all. (C) 2000 Elsevier Science Ltd. All rights reserved.