Regensburg 2004 – wissenschaftliches Programm
O 39.4: Vortrag
Donnerstag, 11. März 2004, 16:30–16:45, H39
Formation of a faceted MoO2 epilayer on Mo(112) studied by XPS, UPS and STM — •Thomas Schroeder1, Tien Lin Lee1, Jörg Zegenhagen1, Norbert Magg2, Boonchuan Immaraporn2, and Hans-Joachim Freund2 — 1E.S.R.F, Beamline ID32, 6, Rue Jules Horowitz, 38043 Grenoble, France — 2Fritz-Haber-Institut, Abt. CP, Faradayweg 4 - 6, 14195 Berlin, Germany
The open trough and row Mo(112) surface serves as substrate for the epitaxial growth of MoO2. XPS, UPS and STM studies of the oxygen adsorption allow to monitor step-by-step the transformation of the electronic and morphological properties during this process. XPS and UPS spectra reveal that a stable oxygen chemisorbed state precedes the formation of MoO2. STM topographs identify this oxygen chemisorbed phase as an oxygen-induced p(2x3) reconstruction of the missing row type. This precursor state evolves into a flat p(1x3) reconstructed (010) MoO2 layer which roughens by the formation of (110) facets under further oxygen exposure.