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β-Ga2O3-based heterojunctions: Effects of growth orientation and alloying on electronic properties

Mohamed Abdelilah Fadla1,*, Khushabu Agrawal2, Paolo La Torraca2, Myrta Grüning1,3, Karim Cherkaoui2, and Lorenzo Stella1

  • *Contact author: m.fadla@qub.ac.uk
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Phys. Rev. Applied 26, 014046 – Published 16 July, 2026

DOI: https://doi.org/10.1103/3vmk-vfcz

Abstract

We investigate the effects of alloying and growth orientation on the electronic properties of the ultrawide bandgap semiconductor β-Ga2O3 and pseudomorphic (AlxGa1−x)2O3 alloy heterojunctions. Band offsets are computed from first principles using density functional theory with the Heyd-Scuseria-Ernzerhof hybrid functional for different aluminum concentrations and four growth orientations, namely, (100)B, (010), (001)B, and (2¯01). Significant variations are found and ascribed to the strained pseudomorphic alloys. The values of the band offsets are fed into technology computer-aided design (TCAD) models of Schottky barrier diodes (SBD). I-V and C-V characteristics from the TCAD models show reasonable agreement with recent experimental measurements in the forward bias region. Discrepancies in the negative bias region are expected due to the ideality of the Schottky junctions considered in this study. Our findings underscore the critical role of growth orientation and strain in the accurate modeling of β-Ga2O3-based SBD.

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Phys. Rev. Applied 26, 014046– Published 16 July, 2026
  • Received 20 June 2025
  • Revised 10 March 2026
  • Accepted 23 June 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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