Ion implantation post-processing of amorphous carbon films

Ion implantation techniques were used to improve the hardness and wear resistance of sputtered hydrogenated amorphous carbon films and cathodic-arc non-hydrogenated amorphous carbon films. Conventional ion implantation and plasma immersion ion implantation and deposition techniques were used to implant the films with Si, Ti, Hf and W ions of mean energies in the ranges of 28-72 and 3-6 keV, respectively, and doses between 1x10(15) and 1x10(17) cm(-2). Nanohardness measurements demonstrated an increase in the apparent film hardness, depending on the type, kinetic energy, and dose of implanted ions. The effect of the ion dose on the microstructure characteristics of implanted carbon films was studied by Raman spectroscopy. Continuous sliding tests and non-contact profilometry revealed an appreciable increase in the wear resistance of the ion implanted films. Differences in the hardness of implanted films are interpreted in terms of microstructural changes caused by competing mechanisms responsible for film densification, irradiation damage and increase of tetrahedral (sp(3)) bond configurations. It is shown that, under certain conditions, ion implantation post-processing techniques may significantly improve the nanohardness and sliding wear resistance of amorphous carbon films. (C) 1999 Elsevier Science S.A. All rights reserved.