title: Adatom kinetics on and below the surface: the existence of a new diffusion channel.
abstract: Employing density-functional theory in combination with scanning tunneling microscopy, we demonstrate that a thin metallic film on a semiconductor surface may open an efficient and hitherto not expected diffusion channel for lateral adatom transport: adatoms may prefer diffusion within this metallic layer rather than on top of the surface. Based on this concept, we interpret recent experiments: We explain why and when In acts as a surfactant on GaN surfaces, why Ga acts as an autosurfactant, and how this mechanism can be used to optimize group-III nitride growth.
authors.affiliation: Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Neugebauer
authors.forename: Tosja K
authors.initials: TK
authors.lastname: Zywietz
authors.forename: Matthias
authors.initials: M
authors.lastname: Scheffler
authors.forename: John E
authors.initials: JE
authors.lastname: Northrup
authors.forename: Huajie
authors.initials: H
authors.lastname: Chen
authors.forename: R M
authors.initials: RM
authors.lastname: Feenstra