title: Surface electromigration patterns in a confined adsorbed metal film: Ga on GaN.
abstract: The mass transport of gallium adatoms in a confined gallium bilayer on GaN(0001) is studied with photoelectron spectromicroscopy with the goal to identify the diffusing species and their lateral distribution during directional surface electromigration and/or "random" thermal diffusion. It has been found that only the gallium atoms from the second layer undergo biased diffusion involving formation of three-dimensional islands. The development of different gallium concentration patterns is described by means of a general model, considering the presence of vacancies and trapping centres for the diffusing atoms.
authors.affiliation: Sincrotrone Trieste, Area Science Park, 34012 Basovizza, Trieste, Italy. alexei.barinov@elettra.trieste.it
authors.forename: Alexei
authors.initials: A
authors.lastname: Barinov
authors.forename: Luca
authors.initials: L
authors.lastname: Gregoratti
authors.forename: Burkhard
authors.initials: B
authors.lastname: Kaulich
authors.forename: Maya
authors.initials: M
authors.lastname: Kiskinova