Controlled fabrication of nanopit patterns on a graphite surface using focused ion beams and oxidation

Abstract

We produced nanopits on a highly oriented pyrolytic graphite substrate arranged in a given pattern with a combination of focused ion beam ͑FIB͒ irradiation and an oxidation process. The FIB irradiation was carried out using a dedicated FIB nanofabrication tool ͓J. Gierak et al., Appl. Phys. A: Mater. Sci. Process. A80, 187 ͑2005͔͒. After oxidation of the sample surface, defects produced by single ions were imaged as one monolayer deep nanopits with scanning tunneling microscopy. The penetration depth of the ions could be measured by oxidation of the defective volume produced on points irradiated with high ion doses. An array of well separated nanopits with a periodicity of 50 nm could be produced.

Morphology and stability of Au nanoclusters in HOPG nanopits of well-defined depth

“…These pits could be created by selective etching of defects introduced by ion beam impact. Several groups, including the authors have followed this idea [26,[31][32][33][34][35][36][37]. Hövel and Barke studied the morphology and electronic structure of gold clusters in great detail [38].…”

Direct-Write Ion Beam Lithography

“…Other types of QDs, such as InAs and InP on GaAs substrate, and Cu 2 O on SrTiO 3 were also produced by other groups. Another set of studies focused on FIB-generated defects on graphite surface, in particular on highly oriented pyrolytic graphite (HOPG) [43], which was found to efficiently trap deposited nanoparticles by dangling bonds [44]. Gold nanoparticles [45], as well as CoPt clusters [46], were templated by this method.…”