超熱酸素原子線による水素化ダイヤモンドライクカーボン薄膜の選択的エッチング

Selective etching of hydrogenated diamond-like carbon thin films by hyperthermal oxygen atomic beams

田川 雅人*; 横田 久美子*; 北村 晃*; 松本 康司*; 山田 倫子*; 神田 一浩*; 新部 正人*; 吉越 章隆 ; 寺岡 有殿; Belin, M.*; Fontaine, J.*

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

宇宙環境下に水素化ダイヤモンドライクカーボン(HDLC)を置いたとき高速の原子状酸素によって材料表面がどの程度劣化するかについて実験室環境で模擬試験を行った。HDLCはプラズマCVD法でSi基板上に作製した。高速の原子状酸素ビームはレーザーデトネーション法で形成した。表面分析には放射光光電子分光法(SRPES),ラザフォード後方散乱法(RBS),弾性反跳分析法(ERDA),X線吸収端微細構造分析法(NEXAFS)を用いた。HDLCに原子状酸素を照射すると、酸素の化学結合状態には大きな変化はないが、炭素と水素の濃度が低下した。sp/sp比が減少したことから、sp状態にある炭素が選択的にエッチングされたと結論した。

Degradation of hydrogenated diamond -like carbon surfaces in space environments by action of high speed atomic oxygen beams has been investigated in laboratory environments. The HDLC was prepared on Si substrates by a plasma CVD method. High speed oxygen atomic beams were generated by a laser detonation method. The HDLC surfaces irradiated by the oxygen atomic beams were analyzed by Synchrotron Radiation Photoemission Spectroscopy (SRPES), Ratherford Backscattering Spectroscopy (RBS), Elastic Recoil Detection Analysis (ERDA), Near-Edge X-ray Absorption Fine Structure (NEXAFS). Although chemical bonding states of oxygen atoms were maintained as they were even after the oxygen atomic beam irradiation, concentrations of carbon and hydrogen were decreased. The sp/sp ratio was also decreased. Consequently, carbon atoms in the sp state were selectively etched out with hydrogen atoms by chemical reactions with oxygen atomic beams.