Diamond-Like Carbon Films Deposited by Plasma-Based Ion Implantation Method

Diamond-like carbon (DLC) films were deposited on Si substrates and high-carbon chromium bearing steel (SUJ2) substrates by a plasma-based ion implantation method using an electron cyclotron resonance (ECR) plasma source with a mirror field and a power supply to apply negative high-voltage pulses and a negative DC bias to the substrate. CH4 gas was used as a carbon source. The plasma was produced from CH4 gas with an ECR power supplier. Before the deposition process of DLC films, carbon ions were implanted into the substrate surface by applying the high-voltage pulses of -10 kV for the formation of a carbon mixing layer. The DLC films with a smooth surface and a low friction coefficient could be formed by applying the negative high-voltage pulses of -2 kV to a substrate with a low duty ratio of 1%. The wear resistance of the DLC films was improved by the formation of the carbon mixing layer. The effect of the mixing layer formed at the interface between the DLC films and the substrate will be discussed in this presentation.