Growth of single atom wide indium islands - chains - on anisotropic Si(100)-2x1 surface was observed by scanning tunneling microscopy (STM), and modelled by kinetic Monte Carlo (KMC) simulations. Experiments were performed for different growth parameters: various deposition rates, and several coverages. The density of islands, and the distribution island sizes were measured. Surface features were modelled using microscopic atomistic model with anisotropic diffusion, and forbidden zones along one-dimensional chains.
The reconstructed surface Si(100)-2x1 may contain various defects. We investigated in particular this aspect because it is known that the presence of impurities or defects may strongly affect the nucleation, and growth of islands [1]. The STM measurements reveal the presence of the C-type defects, and show that deposited indium atoms nucleate with the high preference on these defects. Using a combination of experimental observations and atomistic KMC modelling we analyze the influence of C-type defects on the mechanism of growth of indium on Si(100)-2x1 surface. We study in detail how the island density, and the island size distribution are affected by the inevitable presence of the immobile C-type defects [2]. The dependence of the measured quantities on the concentration of C-type defects is evaluated.
[1] M. Kotrla, J. Krug and P. milauer: Effects of mobile and immobile impurities on two-dimensional nucleation, Surf. Sci. 482-485, 840-843 (2001).
[2] P. Kocán, P. Sobotík, I. Oádal: Comment on "Monotonically decreasing size distribution for one-dimensional Ga rows on Si(100)", Phys. Rev. B 74, 0374001 (2006). |