Ion beam sputtering induced ripple formation in thin metal films

TL;DR

This study investigates ripple formation on thin metal films caused by ion beam sputtering, revealing that surface instability mechanisms are similar to those in amorphous materials, and the ripples are stable under ambient conditions.

Contribution

It demonstrates that ripple formation in polycrystalline metallic films occurs via erosion-induced surface instability, extending understanding beyond amorphous materials.

Findings

Ripples form on Au, Pt, Ag, Cu, Co films under ion sputtering.

Ripples are stable under ambient conditions.

Surface instability mechanism is similar to amorphous materials.

Abstract

We have observed the formation of ripples in a number of thin metal films, e.g. Au, Pt, Ag, Cu and Co under Ar^{+} ion beam sputtering at grazing incidence. The structures are found to be quite stable under ambient conditions. The results show that the ripple formation in polycrystalline metallic films relies on the erosion-induced surface instability similar to that in amorphous materials.