Kinetic Monte Carlo simulation of quantum dot growth on stepped substrates

摘要

The growth of quantum dots (QDs) on various Si platforms often results in a bimodal distribution for the size of the QD. This has been previously attributed to the use of vicinal substrates. In this study, a kinetic Monte Carlo (KMC) simulation using a double-zone model is used to study the formation of QDs on the stepped substrate. In this double-zone model, the substrate is divided into two regions, the step region and the terrace region. An additional activation barrier of E_(step) is introduced for adatoms diffusing in the step region. Preferential nucleation at the step region was observed and the dot size distribution uniformity depends on the growth temperature and the magnitude of Estep.