Vacuum annealing formation of graphene on diamond C(111) surfaces studied by real-time photoelectron spectroscopy

ダイヤモンドC(111)表面における真空加熱によるグラフェン形成のリアルタイム光電子分光による観察

小川 修一*; 山田 貴壽*; 石塚 眞治*; 吉越 章隆 ; 長谷川 雅考*; 寺岡 有殿; 高桑 雄二*

Ogawa, Shuichi*; Yamada, Takatoshi*; Ishizuka, Shinji*; Yoshigoe, Akitaka; Hasegawa, Masataka*; Teraoka, Yuden; Takakuwa, Yuji*

To clarify the graphene formation process on a diamond C(111) surface, changes in the chemical bonding states by annealing in vacuum were investigated by photoelectron spectroscopy using synchrotron radiation. It is difficult to study the formation of sp-bonded carbon atoms on a diamond C(111) surface because the peak of the sp component overlaps the peak of the surface sp component as a result of the 21 reconstruction. Therefore, we focused on the shift in the C 1s photoelectron spectra and energy loss spectra caused by band bending depending on the temperature. As a result, we found that graphitization on the diamond C(111) surface began at approximately 1120 K, which was lower than that for an SiC substrate. The photoelectron spectra indicated that a buffer layer composed of sp-bonded carbon atoms existed at the interface between the graphene and diamond C(111) surface.