Experimental test of the single adatom exchange model in surfactant-mediated growth of Ge on Si(100)

We have tested the single adatom exchange model for surfactant-mediated growth. Using two samples with different coverages of Ge on Sb-terminated Si(100), we generated energy distributions of scattered MeV ions from transmission ion channeling experiments. We studied the system both after room temperature deposition of Ge and after annealing at 350 degrees C. We then compared simulated energy distributions for the single adatom exchange model to the experimental energy distributions. No combination of temperature and coverage produced a good fit between data and simulations of this model. Before annealing. however, a model having Ge in dimer-like sites on top of undisturbed Sb dimers describes the data well for both Ge coverages. (C) 1998 Elsevier Science B.V.