Ion irradiation-induced bimodal surface morphology changes in InSb.

High-energy ion irradiation of InSb results in the formation of bimodal surface structures, namely microscale hillock-like structures fully composed of nanoscale fibers. Analysis of the surface structures by a wide range of electron microscopy techniques reveals correlations between the irradiation conditions, such as the ion energy and fluence, and changes in the surface morphology. Sputtering effects play a key role in the integrity of the surface layer with increasing ion fluence. Possible mechanisms responsible for the morphological transformation are discussed, including both irradiation-induced and mechanical effects.