Medium-energy ion scattering studies of two-dimensional rare-earth silicides

Medium-energy ion scattering (MEIS) has been used to determine the atomic structure of two-dimensional (2D) rare-earth silicides on Si(111). In the case of the Si(111)1×1-Er 2D silicide surface, the MEIS results refine previously published results, but in the case of the Si(111)1×1-Ho surface, this work represents to our knowledge the first full quantitative structural analysis that reveals a structure similar to that of the Si(111)1×1-Er surface and directly supports a model in which a rare-earth monolayer resides below a Si bilayer close to bulklike termination.