Abstract:
We have investigated the influence of Sb on the formation of stacking
faults during Ag(111) growth using x-ray scattering. In equilibrium, a
predeposition of 1/3 monolayer Sb results in a (root 3 X root 3)R 30
degrees reconstruction in which the top layer is wrongly stacked. Upon
continued Ag growth at 100 degrees C, the Sb segregates and the Ag
atoms return to the correct stacking, while the new Ag atoms in the top
layer
again have the wrong stacking. This thus effectively leads to a floating
stacking fault. Because of kinetic limitations, the same effect occurs
for lower
Sb coverages.