Nano-faceting of fcc(110) surfaces controlled by adsorbates and atom deposition or removal

摘要

(110) surfaces of most fcc metals are only marginally stable against faceting into (111) orientations. Trace concentrations of adsorbates (surfactants) that prefer (111) over (110) facets can tip the balance and favor faceting of all or part of the (110) surface. The growth of such facets is impeded by island and vacancy-island nucleation barriers. However, during atom deposition or etching these barriers are reduced. Growth or removal conditions and facet stabilizing surfactant concentrations control the evolving faceted nano-patterns. Recent observations of hut-shaped nanocrystals formation on Al(110) are consistent with this model.