Focused ion beam channeling effects and ultimate sizes of GaAlAs/GaAs nanostructures

Abstract

We show that focused ion beam implantation of Ga into GaAlAs/GaAs quantum wells occurs much deeper than expected from theory of implantation into amorphous GaAs and that the lateral straggling is one order of magnitude smaller than predicted by the same theories. We show that channeling is the main mechanism involved in these effects. The small probe size achieved with the focused ion beam is thus preserved 200 nm below the surface.