The creation of Au nanoscale surface patterns by the low energy Ar + beam irradiation of Au clusters evaporated onto a SiO2/Si surface

Abstract

Ex-situ contact-mode atomic force microscopy (C-AFM) was used to study the evolution of the topography of nanoscale Au clusters, deposited onto SiO2/Si surfaces, as a function of Ar+ beam irradiation. Various nanoscale Au surface patterns were created, at an ion beam energy of 2.5 keV, by controlling the ion beam conditions. These patterns include ordered or disordered spheres as well as a nanoporous metal layer. We found that the original (∼ 4 nm) clusters coalesced, under the ion beam, to form both larger clusters (∼ 9 nm) and a nanoporous interphase layer (∼ 6.5 nm). Under continued irradiation, both the original clusters and the nanoporous layer were absorbed into the larger clusters.