Research Article

Properties of the Horizontal Structural P-Type β-Ga2O3 Schottky Barrier Diode Fabricated by the Thermal Oxidation of GaN in N2O Environment

Hangcheng Zhou 1, Xinping Wang 2, Weijun Chen 3, Sufen Wei 1 *
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1 School of Ocean Information Engineering, Jimei University, Xiamen 361021, China2 School of Science, Jimei University, Xiamen 361021, China3 School of Electronic Science and Technology, Xiamen University, Xiamen 361005, China* Corresponding Author
Applied Functional Materials, 6(2), June 2026, 1-9, https://doi.org/10.35745/afm2026v06.02.0002
Submitted: 21 July 2025, Published: 30 June 2026
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ABSTRACT

Schottky barrier diodes (SBDs) are high-speed, low-power electronic devices that are widely used in high-frequency and microwave communication circuits, as well as in power electronics. In this study, thermal oxidation was employed to convert undoped single-crystal gallium nitride (GaN) into nitrogen-doped polycrystalline β-Ga2O3 in the N2O atmosphere at 1000 °C. A horizontal p-type SBD was fabricated using a "high-magnesium and low-aluminum" alloy (containing 90% Mg and 10% Al by mass) as the circular Schottky contact with a diameter of 2000 μm, directly on the nitrogen-doped β-Ga2O3 film without incorporating a p– β-Ga2O3 drift layer. At room temperature (300 K), under atmospheric conditions, the SBD exhibited favorable rectification characteristics, with an ideality factor of 1.62. Additionally, the temperature-dependent behavior of the Schottky barrier height and ideality factor was investigated under vacuum conditions.
Keywords: Gallium oxide, Schottky barrier diode, Ideality factor

CITATION (APA)

Zhou, H., Wang, X., Chen, W., & Wei, S. (2026). Properties of the Horizontal Structural P-Type β-Ga2O3 Schottky Barrier Diode Fabricated by the Thermal Oxidation of GaN in N2O Environment. Applied Functional Materials, 6(2), 1-9. https://doi.org/10.35745/afm2026v06.02.0002

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