We have investigated the influence of native oxides on ion-sputtering- induced nanostructure formation on GaSb using in situ low energy ion scattering spectroscopy (LEISS) and X-ray photoelectron spectroscopy (XPS). Comparing an oxygen-free sample with a native oxide sample, LEISS and XPS reveal the effect of oxygen in generating higher surface Ga fractions during early stages (fluences of 1 × 1015-1 × 1016 cm -2) of low energy (<100 eV) Ar+ irradiation. Enhanced surface Ga and Ga2O3 fractions were also observed on "oxide free" samples exposed to air following irradiation. The results suggest preferential Ga oxidation and segregation on the top of the amorphous layer if oxygen is present on the surface. In addition, the native oxide also increases the fluence threshold for nanopatterning of GaSb surfaces by almost a factor of four during low energy irradiation.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)