The adsorption of germanium on the Bi/Si(001)-(2 x 5) surface [bismuth satu
ration coverage of 0.7 ML (monolayers)] was investigated by core-level phot
oemission spectroscopy. At submonolayer germanium coverage, the presence of
a bulk component largely dominating the Ge 3d core level demonstrates that
the favourite adsorption sites are the bismuth-terminated terraces. where
Ge-Bi site exchange takes place. At larger germanium coverage, in addition
to the previous process, the occurrence of a purr germanium epitaxy is indi
cated by the presence of the (2 x 1) surface components in the Ge 3d core l
evel. (C) 1999 Elsevier Science B.V. All rights reserved.