Band alignment and electrical properties of Al₂O₃/β-Ga₂O₃ heterojunctions Available to Purchase

The band alignment of Al₂O₃/n-Ga₂O₃ was investigated by x-ray photoelectron spectroscopy (XPS). With a band gap of 6.8 ± 0.2 eV measured for Al₂O₃, the conduction and valence band offsets at the interface were estimated to be 1.5 ± 0.2 eV and 0.7 ± 0.2 eV, respectively. The conduction band offset was also obtained from tunneling current in Al₂O₃/n-Ga₂O₃ (⁠$2¯01$⁠) metal-oxide-semiconductor (MOS) diodes using the Fowler-Nordheim model. The electrically extracted value was in good agreement with the XPS data. Furthermore, the MOS diodes exhibited small capacitance-voltage hysteresis loops, indicating the successful engineering of a high-quality Al₂O₃/Ga₂O₃ interface.