EFFECT OF ION-IMPLANTATION ON ION-PLATED DIAMOND-LIKE CARBON-FILMS

A Raman spectroscopic study has been carried out on the effects of ion implantation of argon or nitrogen on the structures of ion-plated diamond-like carbon (DLC) films. The carbon films were deposited on WC substrates at room temperature, 200, 250, 300 and 350-degrees-C. Implantation of 150 keV Ar+ or N+ into the films was carried out with a dose of 1 x 10(16) ion cm-2 at room temperature. The structure of the carbon films was estimated by laser Raman spectroscopy. It was found that the Raman spectra for non-implanted and implanted DLC films consisted of four main peaks: two well-known peaks belonging to graphite and long-ranged-disordered graphite structures, and two other new peaks which can be considered as follows. One peak corresponds to an amorphous-like structure with C=C bonding, and the other peak corresponds to a kind of hydrogenated-like carbon with chains of alternate C=C and C-C bonds. The as-deposited DLC films had various structures, depending on the ion plating conditions. Ion implantation in DLC specimens changed their structures, making them the same. It is expected that an equilibrium of mutual transfer (amorphous half arrow right over half left -graphite) was achieved during ion implantation.