Identification of Ge/Si intermixing processes at the Bi/Ge/Si(111) surface.
The chemical contrast between Si and Ge obtained by scanning tunneling microscopy on Bi-covered Si(111) surfaces is used as a tool to identify two vertical Ge/Si intermixing processes. During annealing of an initially pure Ge monolayer on Si, the intermixing is confined to the first two layers approaching a 50% Ge concentration in each layer. During epitaxial growth, a growth front induced intermixing process acting at step edges is observed. Because of the open atomic structure at the step edges, relative to the terraces, a lower activation barrier for intermixing at the step edge, compared to the terrace, is observed.
Paul
Neelima
N
Institute of Bio- and Nanosystems (IBN 3), and cni - Center of Nanoelectronic Systems for Information Technology, Research Center Jülich, 52425 Jülich, Germany.
Filimonov
Sergey
S
Cherepanov
Vasily
V
Cakmak
Mehmet
M
Voigtländer
Bert
B