Low ON-State Resistance Normally-OFF AlGaN/GaN MIS-HEMTs With Partially Recessed Gate and ZrOₓ Charge Trapping Layer

Abstract

Novel normally-OFF AlGaN/GaN MIS-high electron mobility transistors (HEMTs) with a ZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> charge trapping layer are proposed. The deposition of the ZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> charge trapping layer on the partially recessed AlGaN in conjunction with the Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> gate dielectric has been accomplished. The developed MIS-HEMTs exhibit a threshold voltage of 1.55 ± 0.4 V and a maximum drain current of 730 ± 6 mA/mm, while associated low ON-resistance of 7.1 ± 0.2 Ω·mm, for a gate to drain separation of 3 μm. The TCAD simulation results are presented to explore the charge trapping and de-trapping behaviors. Moreover, the devices exhibit a high breakdown voltage. The results indicate the merits of employing ZrO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> charge trapping layer to realize the normally-OFF GaN devices with low ON-state resistance.