J. Phys. Colloques
Volume 49, Numéro C6, Novembre 198835th International Field Emission Symposium / 35éme Symposium International d'Emission de Champ
|Page(s)||C6-275 - C6-280|
J. Phys. Colloques 49 (1988) C6-275-C6-280
FIM, RHEED STUDIES ON ATOMATIC STRUCTURE OF Si(111) AND Si(111)-Ag SURFACEST.S. PARK, C.I. CHUNG, S.M. JUNG et D.Z. JEON
Department of Physics, Kyungpook National University, Taegu 702-701, Korea
We have investigated the atomic structure of clean surfaces of Si(111) and Si(111)-Ag surfaces using both FIM and RHEED-TRAXS system. In FIM image of Si at 78K, the surface oxides layers were slowly desorbed as increasing the applied voltage, and then the ring structure of Si(111)surface appeared. From this stage silicon atoms evaporated violently. Ag atoms were deposited on clean Si tip surface by thermal evaporation controlled accurately by a fast thickness monitor which was developed by authors. The desorption of Ag atoms were carried out by direct heating the Si tip. From our FIM and RHEED-TRAXS experimental results we could support the displacement model for the interpretation of Si(111) 7x7 superstructure and Lander-Morrison model for the atomic arrangement of Si(111) √3x√3-Ag structure for Θ=1.0 ML.