Initial stages of Si-molecular beam epitaxy on Si(111) studied with reflection high-energy electron diffraction intensity measurements and Monte Carlo simulations

This is a report on the initial behaviour of homoepitaxial growth of Si on Si(111) based on reflection high-energy electron diffraction (RHEED) intensity measurements and kinetic solid-on-solid Monte Carlo simulations. A quenching of the first RHEED-oscillation corresponding to the first double layer is observed over a wide temperature range. This suppression could be simulated by introducing a defect related, extra activation energy for growth on top of the first and subsequently formed bilayers (BL). As a result of the increased activation energy, the interface width was shown to increase with the substrate temperature at the beginning of the deposition. The gradual return to regular BL-by-BL growth was accomplished by assigning an increased hopping probability to adatoms situated on top of step edges.