title: Nanocrystal formation and faceting instability in Al(110) homoepitaxy: true upward adatom diffusion at step edges and island corners.
abstract: Using atomic force microscopy and spot-profile analyzing low energy electron diffraction, we have observed the existence of a striking faceting instability in Al(110) homoepitaxy, characterized by the formation of nanocrystals with well-defined facets. These hut-shaped nanocrystals are over tenfold higher than the total film coverage, and coexist in a bimodal growth mode with much shallower and more populous surface mounds. We further use density functional theory calculations to elucidate the microscopic origin of the faceting instability, induced by surprisingly low activation barriers for adatom ascent at step edges and island corners.
authors.affiliation: INFM-Unità di Genova and Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, I-16146 Genova, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Buatier de Mongeot
authors.forename: Wenguang
authors.initials: W
authors.lastname: Zhu
authors.forename: A
authors.initials: A
authors.lastname: Molle
authors.forename: R
authors.initials: R
authors.lastname: Buzio
authors.forename: C
authors.initials: C
authors.lastname: Boragno
authors.forename: U
authors.initials: U
authors.lastname: Valbusa
authors.forename: E G
authors.initials: EG
authors.lastname: Wang
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Zhang