Determination of type-ΙΙ band alignment β-Ga2O3/GaAs heterojunction interface by x-ray photoelectron spectroscopy.

A high-quality β-Ga2O3 film was grown on a (111) GaAs substrate using the metal organic chemical vapor deposition method. The band alignment of the β-Ga2O3/GaAs heterojunction interface was determined by x-ray photoelectron spectroscopy. The energy-band structure of β-Ga2O3/GaAs was constructed based on the binding energies of Ga 3d and As 3d core levels as well as valence band maximum values. The valence band offset was determined to be 3.50 ± 0.05 eV. As a consequence, a type-ΙΙ heterojunction with a conduction band offset of 0.12 ± 0.05 eV was determined in the present study. The accurate determination of the band alignment of the β-Ga2O3/GaAs heterojunction provided useful information for the application in β-Ga2O3/GaAs-based devices. [ABSTRACT FROM AUTHOR]