Deposition and characterization of Ti- and W-containing diamond-like carbon films by plasma source ion implantation

Ti and W-containing diamond-like carbon (DLC) films were prepared on silicon wafer substrate by a process combining reactive magnetron sputtering with plasma source ion implantation (PSII). Ti and W were deposited by r.f. magnetron sputtering of a metal target and PSII using hydrocarbon gas. Ar/C2H2 mixed gas was introduced into the discharge chamber. The negative high voltage pulse (−10 kV, 100 Hz, 100 μs) superposed on a d.c. voltage of −0.5 kV was applied to the substrate holder. The structure of the films changed from metal containing amorphous DLC, to a composite of metal containing DLC and metal carbides with increasing metal content in the films. The sheet resistivity of the films was decreased abruptly with increasing metal content in the films. The tribological properties of the films were improved by W doping.