Control of nanostructures induced by ion sputtering

In this paper, the usefulness of the end-point detection (EPD) technique to control the formation of nanostructures during the ion beam sputtering of surface materials is demonstrated using the particular case of Fe/GaAs. The technique allows the interaction of the ions with the sample surface to be monitored through a plot of the stage grounding current as a function of ion sputtering time leading to control over the formation of nanostructures. By choosing different segments in the plot, specific nanostructures can be obtained with good reliability. Even better control can be achieved by using a large ion-sputtering area or by choosing a small beam current, but both of these variations increase the time required for fabrication.