Growth mechanism of Si on Ag(111)

The crystal growth of Si on the Ag(111) has attracted much attention because two dimentional honeycomb structure of Si, as silicene, forms on this substrate below 1 monolayer. Further deposition of Si atoms after the completion of siicene leads the structural transformation into bulk diamond structure, which accopanies the dewetting of silicene layer. The dewetting is induced by increasing the amount of Si on the substrate, even though the temperature is kept constant. This is an exceptional case of the coventional epitaxial growth, and the kinetic mechanism of the growth is interesting. We have performed STM and STS studies to quantitatively evaluate the evolution of geometric and electronic structures during the growth. To simulate the unique growth behavior, we used a kinetic Monte Carlo simulation. The mechanism of the characteristic dewetting growth is discussed based on the experiment and theoretical simulation.