Tribological properties of nitrogen implanted diamond-like carbon

Diamond-like carbon (DLC) films prepared by an ion plating method using C6H6 plasma were implanted with 25 keV nitrogen N-15 ions to a total dose of 5 x 10(17) ions/cm(2) at temperatures up to 900 degrees C. The atomic concentration of the implanted layer was measured by nuclear reaction analysis (NRA) and elastic recoil detection (ERD). Macro- and micro-tribological properties of the implanted layer were examined by a reciprocating tribotester and atomic force microscope (AFM), respectively. It was found that the nitrogen concentration in DLC films implanted at RT saturated at 23%. and a groove was formed by micro-wear on the surface at a low load of 150 nN, whereas the groove was not formed on the unimplanted surface. At 900 degrees C implantation, the maximum concentration of nitrogen was 10%, and nitrogen implanted at high dose diffused into the substrate. (C) 1999 Elsevier Science B.V. All rights reserved.