Formation of protective oxide film with self-healing capability on metal-doped diamond-like carbon films under hyperthermal O-atom collision in LEO space environment

Yokota, Kumiko*; Watanabe, Daiki*; Hatsuda, Akimine*; Yoshigoe, Akitaka ; Teraoka, Yuden; Tagawa, Masahito*

In this study, oxidation of Si-atom in DLC with energetic O-atom was investigated by a combination of broad O-atom beam and synchrotron radiation photoelectron spectroscopy. It was observed that amount of O at the exposed surface showed a peak at a high-energy position. The result clearly indicated that the oxidation efficiency strongly depends on the collision energy. It was also examined that the amount of suboxides decreased with increasing the collision energy of incident O-atom above 4 eV. It was concluded that formation of SiO by the collision of energetic O-atom is promoted with collision energy above 5 eV at room temperature.