XPS diagnostics of GaAs-based semiconductors with surface cleaning by ion etching

Abstract

Ar⁺ etching the surface of GaAs-based semiconductors, required in XPS, drastically changes the core-level binding energies (BEs) in n-GaAs, SI-GaAs and p-GaAs, so that the BE shift can exceed the chemical one. The ion etching forms a p-GaAs surface layer with BEs ∼1.2 eV higher than in n-GaAs. To obtain information about the bulk unirradiated layer, the energy of bombarding ions should be reduced, whereas photon energy and the XPS energy resolution should be increased.