Heterogeneous nucleation and adatom detachment at one-dimensional growth of In onSi(100)−2×1

Abstract

Growth of atomic indium chains---one-dimensional islands---on the $\text{Si}(100)\text{\ensuremath{-}}2\ifmmode\times\else\texttimes\fi{}1$ surface was observed by scanning tunneling microscopy (STM) at room temperature and simulated by means of a kinetic Monte Carlo method. Density of indium islands and island-size distribution was obtained for various deposition rates and coverage. STM observation of growth during the deposition of indium provided information on growth kinetics and relaxation of grown layers. Important role of $C$-type defects at adsorption of metal atoms was observed. Measured growth characteristics were simulated using a microscopic model with anisotropic surface diffusion and forbidden zones along the metal chains. An analysis of experimental and simulation data shows that the detachment of indium adatoms from the chains substantially influences a growth scenario and results in monotonously decreasing chain length distribution function at low coverage. Diffusion barriers determined from the simulations correspond to almost isotropic diffusion of indium adatoms on the surface. The results are discussed with respect to data reported in earlier papers for other metals.