Oxygen adsorption on wet-chemically cleaned GaN(0001) surface studied by coaxial impact collision ion scattering spectroscopy

Abstract

Oxygen adsorption on wet-chemically cleaned GaN(0001) surface has been studied by coaxial impact collision ion scattering spectroscopy (CAICISS). The intensity variation of time-of-flight spectra obtained by CAICISS was compared with simulation results. The CAICISS analysis showed that oxygen is adsorbed at the top of Ga atoms at the surface. The Ga–O bond distance was estimated to be between 1.80 and 1.85 Å. The estimated bond distance is consistent with the Ga–O tetrahedral bond distance in β-Ga2O3.