AVS 45th International Symposium
    Surface Science Division Thursday Sessions
       Session SS2-ThA

Paper SS2-ThA9
Morphology of MgO (111) Surfaces: Artifacts Associated with the Faceting of Polar Oxide Surfaces into Neutral Surfaces

Thursday, November 5, 1998, 4:40 pm, Room 309

Session: Oxide Growth and Structure
Presenter: M. Gajdardziska-Josifovska, University of Wisconsin, Milwaukee
Authors: R.A. Plass, University of Wisconsin, Milwaukee
J. Feller, University of Wisconsin, Milwaukee
M. Gajdardziska-Josifovska, University of Wisconsin, Milwaukee
Correspondent: Click to Email
We have found using optical, atomic force, scanning and transmission electron microscopies that the polar ionic MgO (111) surface does not facet into neutral (100) type planes upon high temperature annealing, as has been commonly believed, rather it appears to be stabilized by surface reconstructions containing cyclic ozone. The triangular pyramidal pits which Henrich@footnote 1@ associated with this presumed faceting turn out to be artifacts of the acid etch used in the sample preparation process. We have determined that the pits have walls sloped at 10.8° ± 2.8 ° with respect to the (111) surface, not the 54.7° expected for faceting to (100) type planes. The pit edges were confirmed by transmission electron microscopy to be along the three equivalent <110> type directions. The morphology of this surface before and after annealing as well as transmission electron diffraction data and proposed atomic structures of three native surface reconstructions seen after annealing will be discussed. @FootnoteText@ @footnote 1@V.E. Henrich, Surf. Sci., 57 (1976) 385