Valence band offset at Al_2O_3ZIn_(0.17)Al_(0.83)N interface formed by atomic layer deposition

摘要

The valence band offset, △E_y, at an Al_2O_3/In_(0.17)Al_(0.83)N interface formed by atomic layer deposition was measured by x-ray photoelectron spectroscopy. The conventional method of using the core level separation, △E_(CL), between O Is and In 4d resulted in △E_v= 1.3 eV, which was apparently consistent with the direct observation of the valence band edge varying the photoelectron exit angle, θ. However, △E_(CL) and full width at half maximum of core-level spectra were dependent on 9, which indicated significant potential gradients in AI_2O_3 and InAIN layers. An actual △E_v of 1.2 eV was obtained considering the potential gradients.