Published online by Cambridge University Press: 21 February 2011
The growth of submonolayer Pb-films on Cu (100) and (111) was investigated by a 3-dimensional Monte Carlo simulation based on the Metropolis technique. The system Cu/Pb was studied because of its known immiscibility. Two different types of potentials have been chosen to simulate the interaction of deposited film atoms mutually and with the substrate surface: (a) Morse- and (b) Embedded Atom (EAM)-potential. Especially by varying the unknown Morse-potential parameters of the Cu-Pb interaction we observed all stages from layer-by-layer growth to surface alloying. At the Cu (111) surface both potentials led to a preferred adsorption site by decorating a Cu step with Pb atoms. Also a seam of embedded Pb atoms parallel to the step edge on the upper side of a monoatomic Cu step was observed. The early stages of a Pb film growing on Cu (100) are characterized by forming different types of superstructures. Surface total energy calculations were performed and compared with STM results. Most of the results are in accordance with experimental results and observations by scanning tunnel microscopy.