Auger Electron Spectroscopy Study of Cleaved and Sputter-Etched In0.53Ga0.47As Surfaces

Quantitative Auger electron spectroscopy (AES) analysis of In0.53Ga0.47As prepared by liquid phase epitaxy on InP (100) substrate has been performed. We first characterized the composition of the as-grown (100) and cleaved (110) surfaces, which have been found to be indium enriched and stoichiometric respectively. We then systematically investigated the modifications induced in the surface and subsurface region by an Ar+ beam of energy 1–5 keV. The in-depth composition has been obtained via angle-resolved AES and low energy sputter profiling of the high-energy-processed surfaces. Similar results have been obtained on the different crystallographic planes. The surface is anion depleted, while a significant enhancement in the Ga:In relative concentration occurs in the subsurface region. The measured composition profiles suggest that different mechanisms, namely preferential sputtering and radiation-enhanced surface segregation, are cooperative in determining the modifications of the ion-bombarded surfaces.