Regensburg 2004 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
O: Oberflächenphysik
O 34: Oxide und Isolatoren
O 34.1: Talk
Thursday, March 11, 2004, 11:15–11:30, H45
Investigations of SrO and BaO on the Si(001) surface — •J. Zachariae and H. Pfnür — Institut für Festkörperphysik, Universität Hannover, Appelstr. 2, 30167 Hannover
In an attempt to generate epitaxial medium k (єr≈30) BaO /SrO films we investigated the growth conditions, crystalline quality and stoichiometry using high resolution LEED, UPS, XPS and EELS. Epitaxial SrO and lattice matched Ba1−xSrxO layers were grown on a Sr/Si(001) interface in UHV by evaporation of the metals in a ambient oxygen pressure. The quality of oxide layers strongly depends on two conditions: The kind of interface e.g. a (5×1)-reconstructed Sr-layer and the accurate oxygen dose, which was determined by mass accumulation on a quartz crystal micro balance. A correct fraction of Ba and Sr in the mixed oxide layers leads to well ordered and lattice matched oxide films from a few monolayers up to 20 nm and more, as seen by the sharper (1×1)-LEED-pattern of the Ba1−xSrxO layers compared to the pattern of the SrO layers. The electronic structure as a function of the interface properties and the layer thickness will be discussed.