Nucleation and growth of Ge nanoclusters on the Si(111)-(7 × 7) surface studied by scanning tunneling microscopy

Abstract

Nucleation and growth of two-dimensional Ge nanoclusters on the Si(111)-(7 × 7) surface at elevated substrate temperatures have been studied using scanning tunneling microscopy. The uniformity of the Ge nanoclusters is improved with the increase of substrate temperature, and ordered Ge nanoclusters are formed on the faulted and unfaulted halves of (7 × 7) unit cell at substrate temperature of 200°C. It is proposed that the Ge nanoclusters consist of six Ge atoms with three on top of the center adatoms and others on the rest atoms within one half of a unit cell.