Abstract
Diamond-like carbon (DLC) is of great interest due to superior properties as a coating material, e.g., high hardness, high wear resistance and chemical stability. Recently, a focused ion-beam assisted chemical vapor deposition (FIB-CVD) method is proposed as a new technique for fabricating three dimensional micro- and/or nano- structures of DLC. Microstructures of this material are, however, not clear sufficiently so far. In this study, therefore, microstructures of DLC produced by the FIB-CVD method were examined. DLC films were prepared on three kinds of substrates by the FIB-CVD method. The microstructures of the films were characterized by high-resolution transmission electron microscopy (HRTEM) equipped with energy dispersive spectroscopy (EDS) and electron energy loss spectroscopy (EELS). For the films on all substrates, HRTEM images and diffraction images indicated that the DLC films had amorphous structures. EDS analysis also indicated that Ga was included 3∼5 at.% and distributed homogeneously in all over the DLC films. The sp3 fraction in the DLC was estimated at 31∼32 % from EELS spectra. It was found that the microstructures, the Ga content and sp3 fraction were independent on substrates.
