Controlled growth of Zn nano-dots on a Ss(111)-7X7 surface saturated with C2H5OH

摘要

Metal atoms bonded with Si adatoms on the Si(111)-(7 X 7) surface undergo migration by hopping adjacent Si-rest atoms with dangling bond. By saturated adsorption of Si(111)-(7 X 7) surface with C2H5OH, the whole Si-rest atoms and a half of Si adatoms are occupied with Si-H and Si-OC2H5, so that the Zn atoms adsorbed on this surface cannot migrate by hopping. When Zn atoms were deposited on this surface, ca. 5 nm Zn dots were grown in the hexagonal spacing of ca. 5.4 nm width around the corner holes, which work as a mold. This is quite different from the growth of honeycomb layers composed of Zn3 clusters on the clean Si(111)-(7 X 7) surface. The dots grow up to nine (1.97 nm) to 13 layers (2.64 nm) by keeping their size, which implies a layer-by-layer growth of dots in the mold, where the growth is controlled by the kinetics instead of energetic feasibility.