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SnO/β-Ga2O3 heterojunction field-effect transistors and vertical p-n diodes

K. Tetzner1, K. Egbo2, M. Klupsch1, R.-S. Unger1, A. Popp3, T.-S. Chou3, S.B. Anooz3, Z. Galazka3, A. Trampert2, O. Bierwagen2, and J. Würfl1

Published in:

Appl. Phys. Lett., vol. 120, no. 11, pp. 112110, doi:10.1063/5.0083032 (2022).


In this work, we report on the realization of SnO/β-Ga2O3 heterojunction vertical diodes and lateral field-effect transistors for power electronic applications. The p-type semiconductor SnO is grown by plasma-assisted molecular beam epitaxy on n-type (100) βGa2O3 with donor concentrations of 3×1017 cm-3 for the diode devices and 8.1×1017 cm-3 for the field-effect transistors. The deposited films show a predominant SnO (001) phase featuring a hole concentration and a mobility of 7.2×1018 cm-3 and 1.5 cm2/V s, respectively. The subsequent electrical characterization of the heterojunction diodes and field-effect transistors show stable switching properties with on/off current ratios >106 and specific on-resistances below 4 mΩ cm2. Furthermore, breakdown measurements in air of the non-field-plated heterojunction transistor with a gate-to-drain distance of 4 µm yield a breakdown voltage of 750 V, which equals an average breakdown strength of nearly 1.9 MV/cm. The resulting power figure of merit is calculated to 178 MW/cm2 demonstrating state-of-the-art properties. This emphasizes the high potential of this heterojunction approach.

1 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin, Germany
2 Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e.V., Hausvogteiplatz 5-7, 10117 Berlin, Germany
3 Leibniz-Institut für Kristallzüchtung (IKZ), Max-Born-Straße 2, 12489 Berlin, Germany


Heterostructures, Power electronics, Electrical properties and parameters, Hall effect, Field effect transistors, Semiconductors, Oxides, Epitaxy, Electrical characterization, Raman spectroscopy

Copyright © 2022 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). https://doi.org/10.1063/5.0083032

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