Self-organized surface nanopatterning by ion beam sputtering

TL;DR

This paper reviews recent advances in ion beam sputtering for creating nanopatterns on surfaces, comparing experimental results with theoretical models, and highlighting open issues especially for nanodots on amorphizable targets.

Contribution

It provides a comprehensive overview of experimental and theoretical studies on ion-beam-induced nanopatterning, emphasizing unresolved questions and the comparison between models and experiments.

Findings

Nanopatterns can be controlled by ion beam parameters.

Discrepancies exist between experimental results and models.

Open issues remain for nanodot pattern formation.

Abstract

The production of nanopatterns on the surfaces of targets irradiated by ion beams at low and intermediate energies has developed during the present decade to a salient degree of control over the main pattern features. However, there is still a wide experimental scatter in the type and relevance of various dynamic interfacial properties induced by this technique as a function of system type and parameters. In parallel, diverse theoretical models exist that differ in their capabilities to reproduce such a wide range of experimental features. We provide an overview of the most recent studies of nanoripple and dot production by ion-beam sputtering, with special attention to the comparison between experiments and (continuum) models, and with a focus on those issues that remain open or, at least, ambiguous. These are perhaps more evident for the case of nanodot patterns on amorphizable targets than for the case of nanoripples due, possibly, to the relative novelty of the former. The pattern properties to be considered are those of potential increased technological importance, such as the variation of nanodot size with parameters like ion energy, target temperature and sputtering time (i.e., fluence), as well as the conditions under which the quality of the pattern order is enhanced, issues such as wavelength coarsening and order enhancement becoming relevant.