Sizes and distances of metal clusters in Au-, Pt-, W- and Fe-containing diamond-like carbon hard coatings

Metal-containing diamond-like carbon hard coatings (Me-DLC) consist of nanometer sized metallic particles, embedded into a highly cross-linked amorphous hydrocarbon matrix. Their mechanical, tribological and electrical properties are strongly influenced by the size and density of metallic inclusions within the film. In this paper a systematic investigation of mean sizes and mean centre-of-mass distances of metal clusters in Me-DLC films will be presented. Sizes and distances have been determined as a function of metal content of the films between 0 and 50 at%. Me-DLC films with four different kinds of metals: gold, platinum, tungsten and iron have been analysed, each by four complementary analytical techniques: small angle X-ray scattering, wide angle X-ray diffraction, transmission electron microscopy and scanning tunnelling microscopy. A comparision of results of the different materials will be given as well as a comparison of the suitability of analytical techniques for this special application.