Simulation of Surfactant Effects on Growth of Semiconductor Hetero-Epitaxial Sb-Ge/Si(111)

A kinetic Monte Carlo simulation is performed in order to study the effect of Sb as a surfactant on the growth of Ge/Si(111).In our model the exchange mechanism between Ge and Sb atoms and the re-exchange mechanism in which the exchanged Ge adatom re-exchange with the lifted Sb atom to return to the surfactant layer,are considered. Our simulation shows the re-exchange process plays an important role on the growth mode transition in Ge/Sb/Si(111) system.The influences of the substrate temperature and the deposition rate on the growth of Ge/Sb/Si(111) system is discussed.