AlGaN/GaN-based normally-off GaN MOSFET with stress controlled 2DEG source and drain

AlGaN/GaN-based normally-off GaN MOSFET with stress controlled 2DEG source and drain was proposed and fabricated using Al₂O₃ gate oxide deposited on the fully recessed gate region. The proposed normally-off Al₂O₃/GaN MOSFET utilized AlGaN/GaN heterostructure source and drain with extremely high 2DEG density of 1.87×10¹⁴ cm² with mobility of 120 cm²V^-1s^-1 and the device results were compared to those obtained from the reference device with normal AlGaN/GaN heterostructure source and drain with 2DEG density of 1.33×10¹³ cm2 and mobility of 1070 cm²V ^-1s^-1. The maximum drain current and maximum transconductance of the proposed device were 263 mA/mm and 72 mS/mm, respectively, about 7.3-times and 5-times larger than those of the reference device, which are comparable to or even higher than one of the best results obtained from various GaN MOSFETs reported by others.