High Breakdown-Voltage (>2200 V) AlGaN-Channel HEMTs With Ohmic/Schottky Hybrid Drains

Abstract

In this paper, a high breakdown voltage of more than 2200 V in high-electron-mobility transistors (HEMTs) with AlGaN channel and a novel ohmic/Schottky-hybrid drain contact is achieved, which is the record breakdown voltage ever achieved on AlGaN-channel HEMTs. The fabricated device exhibits a high on/off ratio of 7×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9</sup> and a low subthreshold swing of 64 mV/decade, enabled by the AlGaN channel and wet treatment. Furthermore, it exhibits excellent high-temperature output characteristics and dynamic I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> -V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> characteristics. Even though both the AlGaN channel and the ohmic/Schottky-hybrid drain have certain impact on the on-state resistance because of the higher sheet resistance and drain contact resistance, these results indicate the significance and potential of AlGaN-channel HEMTs with a hybrid drain architecture in high-voltage applications.