Adatom kinetics on and below the surface: the existence of a new diffusion channel.
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.
Neugebauer
Jörg
J
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany.
Zywietz
Tosja K
TK
Scheffler
Matthias
M
Northrup
John E
JE
Chen
Huajie
H
Feenstra
R M
RM