Valence band offset of InN/BaTiO3 heterojunction measured by X-ray photoelectron spectroscopy

Abstract

X-ray photoelectron spectroscopy has been used to measure the valence band offset of the InN/BaTiO₃ heterojunction. It is found that a type-I band alignment forms at the interface. The valence band offset (VBO) and conduction band offset (CBO) are determined to be 2.25 ± 0.09 and 0.15 ± 0.09 eV, respectively. The experimental VBO data is well consistent with the value that comes from transitivity rule. The accurate determination of VBO and CBO is important for use of semiconductor/ferrroelectric heterojunction multifunctional devices.