XPS–AES study of the surface composition of GaSb single crystals irradiated with low energy Ar ions

Detailed XPS and Auger analysis has been carried out in situ during the formation of nanostructures on GaSb surfaces under low energy Ar+ beam sputtering. A model is suggested to correlate the geometry of the formed nanostructures with the elemental Ga and Sb concentrations at the surface after the ion bombardment. This model is based on the assumption that the nanodots formed during bombardment are Ga enriched. This assumption enables the calculation of the dot surface coverage. The obtained values agree very well with the experimental ones measured by using high resolution scanning electron microscopy.

► Nanopatterning formation from low energy ion sputtering on GaSb studied.
► Model suggested in terms of dot coverage and Sb preferential erosion.
► Effect of the amorphous layer discussed.
► XPS, AES and SEM characterisation of nanodots in GaSb.