In-situ observation of oxidation on Si(111)-77 surface at room temperature by use of synchrotron radiation X-ray photoelectron spectroscopy

Yoshigoe, Akitaka; Teraoka, Yuden

no journal, , 

We present the in-situ observation of oxidation processes on the Si(111)-77 surface at room temperature by use of synchrotron radiation X-ray photoelectron spectroscopy. The initial sticking probability and the density of adsorbed oxygen at saturation were evaluated from the oxygen uptake curve measurement and were investigated as a function of the incident energy from 0.03 eV to 2.3 eV region. The trapping-mediated adsorption process is dominant at the incident energy of lower than 0.06 eV and the direct adsorption mechanism becomes the major dissociative adsorption process over 0.06 eV. The amount of oxygen adsorbates increases at the incident energy more than 0.4 eV. We found that the component of "insx2-tri" adsorption state which corresponding to the dissociataive adsorption state at sub-surface increases over 0.4 eV region from the analnysis of O1s photoelectron spectrum.