Dynamic Behavior of Si Magic Clusters on Si(111) Surfaces

Abstract
In a scanning tunneling microscope (STM) study of Si(111) surfaces from room temperature to 600 °C, we find a special type of clusters which are not only stable with respect to surface diffusion, but are also the fundamental unit in mass transport phenomena, step fluctuations in detachment and attachment of Si atoms at step edges, and epitaxial growth. Using Arrhenius analysis, we derive path specific hopping rate parameters for these clusters. A concerted reaction model is proposed to explain the nucleation and growth behavior of Si on Si(111).