Real-time photoelectron spectroscopy study of 3C-SiC nucleation and growth on Si(001) surface by carbonization with ethylene

エチレンを用いた炭化によるSi(001)表面上での3C-SiCの核形成と成長のリアルタイム光電子分光研究

穂積 英彬*; 小川 修一*; 吉越 章隆 ; 石塚 眞治*; Harries, J.; 寺岡 有殿; 高桑 雄二*

Hozumi, Hideaki*; Ogawa, Shuichi*; Yoshigoe, Akitaka; Ishizuka, Shinji*; Harries, J.; Teraoka, Yuden; Takakuwa, Yuji*

Si(001)表面へのCH曝露による3C-SiC合金層形成において核発生までに時間遅れが存在する。この時間遅れではSiC合金層が形成されるが、その化学結合状態の変化は未だ明らかになっていない。そこで、3C-SiC合金層形成過程を明らかにするため、Si(001)基板の炭化反応過程をリアルタイムXPSで観察した。実験はSPring-8のBL23SUの表面化学反応解析装置にて行った。C1sのピーク分離からSiCの核発生は約8000sとわかり、このときのC1s, Si2p光電子強度から臨界炭素濃度は17%であると求まった。

It is reported that SiC alloy layer was formed on an Si(001) surface with CH exposure at 933 K before nucleation. However information of the chemical bonding state and concentration of adsorbed carbon has not been clear. Therefore the carbonization reaction kinetics on an Si(001) surface reacted with CH exposure was observed by real-time XPS to investigate the 3C-SiC nucleation kinetics. The experiments were performed at the BL23SU of SPring-8. It is suggested that the C1s spectra is composed of at least three chemically-shifted components, which are assigned to carbon-poor SiC alloy, carbon-rich SiC alloy and 3C-SiC. The 3C-SiC nuclei began to generate at 8000s. Using C1s and Si2p peaks, carbon concentration of the SiC alloy layer was estimated to be about 0.17 of x. Therefore it is suggested that critical carbon concentration is 17%.