Study on metal-doped diamond-like carbon films synthesized by cathodic arc evaporation

In this study, we developed a novel method of synthesizing metal-doped diamond-like carbon films (DLC) using the cathodic are evaporation (CAE) process. Intense Cr plasma energy activated the decomposition of hydrocarbon source gas C2H2 to form a metal-doped amorphous carbon film on steel substrates. We deposited a Cr interlayer to prevent interdiffusion between DLC and the steel substrates. When the C2H2 partial pressure is higher than 1.3 Pa, the deposition reaction switched from Cr3C2 to DLC formation. The result is a hydrogenated DLC thin film possessing excellent microhardness as high as 3824 Hv(25g), and for which the incorporation of a Cr interface and Cr doping in the DLC matrix ensure film ductility and sufficient film adhesion. We employed Raman spectroscopy to evaluate the influences of reactive gas flow and substrate bias on the DLC composition; we carried out the microstructure and mechanical property measurements by scanning electron microscopy (SEM), X-ray diffraction (XRD), glow discharge optical spectroscopy (GDS) and wear tests. (C) 2000 Elsevier Science S.A. All rights reserved.