Chemical reactions of hydrogenated diamond-like carbon thin films with oxygen atoms

Tagawa, Masahito*; Yokota, Kumiko*; Matsumoto, Koji*; Kitamura, Akira*; Yamada, Noriko*; Kanda, Kazuhiro*; Niibe, Masahito*; Yoshigoe, Akitaka ; Teraoka, Yuden; Belin, M.*; Fontaine, J.*

We have investigated on degradation of hydrogenated diamond-like carbon (HDLC) surfaces by atomic oxygen beams for space environments under laboratory environments. HDLC was formed on silicon surfaces by a plasma CVD method. The atomic oxygen neams were generated by a laser detonation method. The HDLC surfaces modified by the atomic oxygens were analyzed by Synchrotron Radiation Photo-Emission Spectroscopy (SRPES), Ratherford Backscattering Spectroscopy (RBS), Elestic Recoil Detection Analysis (ERDA), Near-Edge X-ray Absorption Fine Structure method (NEXAFS). Chemical bonding states of oxygen atoms were almost maintained as they were. Concentrations of carbon and hydrogen, sp/sp ratio were decreased by the action of oxygen atoms. We concluded that carbon atoms in the sp state were selectively etched out.