Valence and conduction band offsets in AZO/Ga2O3 heterostructures.

We report on the determination of band offsets in rf-sputtered Aluminum Zinc Oxide (AZO)/single crystal β-Ga 2 O 3 (AZO/Ga 2 O 3 ) heterostructures using X-Ray Photoelectron Spectroscopy. The bandgaps of the materials were determined by Reflection Electron Energy Loss Spectroscopy as 4.6 eV for Ga 2 O 3 and 3.2eV for AZO. The valence band offset was determined to be −0.61eV ± 0.23eV, while the conduction band offset was determined to be −0.79 ± 0.34 eV. The AZO/Ga 2 O 3 system has a nested, or straddling, gap (type I) alignment and provides a convenient method for reducing contact resistance on Ga 2 O 3 -based device structures. [ABSTRACT FROM AUTHOR]