Real-time photoelectron spectroscopy and first-principle calculations study of very thin oxide formation on Si(111)77 surfaces

Si(111)77表面における極薄酸化膜形成のリアルタイム光電子分光と第一原理計算による研究

Tang, J.*; 西本 究*; 小川 修一*; 吉越 章隆 ; 石塚 眞治*; 渡辺 大輝*; 寺岡 有殿; 高桑 雄二*

Tang, J.*; Nishimoto, Kiwamu*; Ogawa, Shuichi*; Yoshigoe, Akitaka; Ishizuka, Shinji*; Watanabe, Daiki*; Teraoka, Yuden; Takakuwa, Yuji*

The surface electronic properties corresponding to real-time photoelectron spectroscopy have been analyzed by density functional theory and molecular orbital calculations to clarify the reaction path of the oxygen adsorption on Si(111)77. The change of work function was observed during the oxidation at room temperature and 873 K. It can be seen that the net charge of atom present at the surface is negative in the oxygen configurations of ad-insx2, ad-insx3, tri-insx3 and the surface electron negativity turns high with increasing oxidation state, implying the change of work function increases drastically at ad-insx3 and tri-insx3. However, the surface is electron positive for insx2 and insx3, leading to the decrease of change of work function. With combining the O1s binding energy calculated by DVXa, potential energy surface calculations and the XPS measurements, a reaction path of the oxygen adsorption on Si(111) is suggested.