Observation of graphitic and amorphous structures on the surface of hard carbon films by scanning tunneling microscopy

The atomic structure of the surface of amorphous hard carbon films, prepared by dc magnetron sputtering, has been studied by scanning tunneling microscopy. Small graphitic domains of ? 15 A{} have been observed. In many disordered areas, five-membered carbon rings were often detected. Other ordered domains are observed which could be interpreted as due to small diamondlike clusters.