ATOMIC STRUCTURE OF A SINGLE STEP AND DYNAMICS OF Sn ADATOMS ON THE Si(111)- v3 ? v3-Sn SURFACE

The atomic structure of single steps on the Si(111)- 3 3 ? -Sn surface and the dynamics of Sn adatoms in the vicinity of these steps were studied. The work was performed using scanning tunneling microscopy (STM) and ab initio calculations based on the density functional theory. The atomic structure model of the single steps consisting of Sn atomic chains along the steps was developed. This structure leads to the formation of potential double-wells near the steps acting as traps for Sn atoms and explains the fluctuating tunneling current recorded in these areas.