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arXiv · 2504.12685

High Breakdown Electric Field (> 5 MV/cm) in UWBG AlGaN Transistors

Seungheon Shin·Hridibrata Pal·Jon Pratt·John Niroula·Yinxuan Zhu·Chandan Joishi·Brianna A. Klein·Andrew Armstrong·Andrew A. Allerman·Tomás Palacios·Siddharth Rajan
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Abstract

We report on the design and demonstration of ultra-wide bandgap (UWBG) AlGaN-channel metal-insulator heterostructure field effect transistors (HEFTs) for high-power, high-frequency applications. We find that the integration of gate dielectrics and field plates greatly improves the breakdown field in these devices, with state-of-art average breakdown field of 5.3 MV/cm (breakdown voltage > 260 V) with an associated maximum current density of 342 mA/mm, and cut-off frequency of 9.1 GHz. Furthermore, low trap-related impact was observed from minimal gate and drain lag estimated from pulsed I-V characteristics. The reported results provide the potential of UWBG AlGaN HEFTs for the next generation high-power radio frequency applications.

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Seungheon Shin, Hridibrata Pal, Jon Pratt, John Niroula, Yinxuan Zhu, Chandan Joishi, Brianna A. Klein, Andrew Armstrong, Andrew A. Allerman, Tomás Palacios, Siddharth Rajan. 2025-04-17. High Breakdown Electric Field (> 5 MV/cm) in UWBG AlGaN Transistors. https://doi.org/10.1063/5.0276718

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