Abstract
Understanding the adsorption of adatom on the surface of an adsorbent and its interaction with defect sites should be considered in tailoring the growth of one-dimensional (1D) chains. Kinetic Monte Carlo simulation of a suitable atomistic lattice-gas model describing the adsorption and 1D submonolayer growth of Al and In on Si(100): 2 × 1 was performed to investigate the resulting nanowire morphology in the presence of various C-defect densities at various deposition temperatures. Average island density (Nav) in Al/Si (100) generally obeys the classically predicted Arrhenius behaviour as temperature increases. By contrast, In adatoms exclusively nucleate on C defect, where Nav is equivalent to defect density. In Al/Si (100) and In/Si (100), Nav showed linear and ‘power law’ dependence on coverage, respectively, whereas the average island size (Sav) for both systems showed linear dependence on coverage. The nanowires morphology in the Al/Si (100) system showed considerable dependence on flux variation. Because of the low-diffusion barrier of In adatom and high-detachment barrier on C defect, In/Si (100) is insensitive to flux. Morphology of In chains is dictated by the defect density: an increase in defect density caused higher island density and smaller island sizes irrespective of coverage and flux rates.
