Generation and nucleation of adatoms during ion bombardment of Pt(111)

Abstract

The morphology of a Pt(111) surface has been investigated by scanning tunneling microscopy after low-energy ${\mathrm{Ar}}^{+}$-ion bombardment as a function of the target temperature during sputtering. On the surfaces sputtered below 550 K, Pt-adatom islands located on the initial surface layer are observed. Their existence is related to a substantial generation of adatoms during the ion bombardment, which has been predicted theoretically. The absence of the Pt-adatom islands on samples sputtered at temperatures above 550 K is correlated with the disappearance of the three-dimensional-growth mode in the homoepitaxy of Pt on Pt(111) above 500 K.