Diamond-like amorphous carbon films prepared by r.f. sputtering in argon : electron-assisted investigations
Abstract We reliably verified by various electron-assisted methods (electron probe microanalysis, scanning electron microscopy, cross-sectional transmission electron microscopy (XTEM), high resolution XTEM, TEM, radial distribution function, electron energy loss spectroscopy) the impurities, morphology and atomic structure which are important for the macroscopic film behaviour of diamond-like carbon films r.f. sputtered in argon at different target voltages, cooled and uncooled. The relatively smooth surface morphology of our low nitrogen-1 and argon-contaminated films depends on target voltage and substrate temperature. Until now, the influence of up to 4.2 at.% oxygen impurities on our resulting solid state has not been clear. We find in comparison with earlier investigations of the physical film properties for our low hydrogen, hard, IR-transparent amorphous carbon films a dominating film structure of irregular cross-linked regions of sp 2 -hybridized carbon predominantly arranged in six-membered rings.