Adsorption of O-2 and CO2 on the Si(111)-7 x 7 surfaces

作者：Wang Shuai; He Jinghui; Zhang Yongping; Xu Guo Qin^*

来源：Surface Science, 2012, 606(17-18): 1387-1392.

DOI：10.1016/j.susc.2012.04.026

• Silicon oxidation
• X-ray photoelectron spectroscopy
• Oxygen
• Carbon dioxide

The interaction of O-2 and CO2 with the Si(111)-7 x 7 surface has been studied with X-ray photoelectron spectroscopy (XPS). It was found that both O-2 and CO2 molecules can readily oxidize the Si(111)-7 x 7 surface to form thin oxide films. Two oxygen species were identified in the oxide film: oxygen atoms binding to on-top sites of adatom/rest atoms with an 0 1s binding energy of similar to 533 eV as well as to bridge sites of adatom/rest atom backbonds at similar to 532 eV. These two oxygen species can be interconverted thermally during the annealing process. Due to the low oxidation capability, the silicon oxide film formed by CO2 has a lower O/Si ratio than that of O-2.

• 出版日期2012-9