2002 年 29 巻 1 号 p. 44-49
The step structure transition between a regular step and a bunched step on vicinal Si (111) surfaces induced by DC is studied by the kinetic Monte Carlo simulation in a terrace-adatom-step-kink (TASK) model of a vicinal surface. In the TASK model, effective force due to DC is taken into account explicitly on both diffusion process of Si adatoms and capture/emission process at a step edge. In the capture-limited regime, step bunching is induced by stepdown force and a regular step is formed by step-up force, corresponding to the experimental temperature range I. In the diffusion-limited regime, step bunching is induced by step-up force and in-phase wandering is induced on a regular step by step-down force, corresponding to the experimental temperature range II. The relation of the two regimes with "non-transparent" and "transparent" conditions at step edges is discussed.