Punchthrough-Voltage Enhancement of AlGaN/GaN HEMTs Using AlGaN Double-Heterojunction Confinement

E. Bahat-Treidel, O. Hilt, F. Brunner, J. Würfl, and G. Tränkle

Ferdinand-Braun-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Straße 4, 12489 Berlin, Germany

Published in:
IEEE Trans. on Electron Devices, vol. 55, No. 12, pp. 3354-3359, (2008).
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Abstract:
In this paper, we present an enhancement of punchthrough voltage in AlGaN/GaN high-electron-mobilitytransistor devices by increasing the electron confinement in the transistor channel using an AlGaN buffer-layer structure. An optimized electron confinement results in a scaling of punchthrough voltage with device geometry and a significantly reduced subthreshold drain leakage current. These beneficial properties are pronounced even further if gate-recess technology is applied for device fabrication. Physical-based device simulations give insight in the respective electronic mechanisms.

Index Terms:
AlGaN/GaN high-electron-mobility transistor (HEMT), breakdown voltage, double heterojunction (DH), gate recess, punchthrough voltage, scale-up.

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