Magic islands and barriers to attachment: A Si/Si(111)7x7 growth model

Surface reconstructions can drastically modify growth kinetics during initi al stages of epitaxial growth as well as during the process of surface equi libration after termination of growth. We investigate the effect of activat ion barriers hindering attachment of material to existing islands on the de nsity and size distribution of islands in a model of homoepitaxial growth o n a Si(111)7 x 7 reconstructed surface. An unusual distribution of island s izes peaked around "magic" sizes and a steep dependence of the island densi ty on the growth rate are observed. "Magic" islands (of a different shape a s compared to those obtained during growth) are observed also during surfac e equilibration. [S0163-1829(99)08343-5].