Recess-Free Normally-off GaN MIS-HEMT Fabricated on Ultra-Thin-Barrier AlGaN/GaN Heterostructure

In this work, a recess-free thin AlGaN barrier metal-insulator-semiconductor high electron mobility transistor (MIS-HEMT) with high threshold voltage of 3.19V, high maximum drain current of 716 mA/mm and high breakdown voltage of 906V is demonstrated for the first time. Three different thin barrier structures were compared for device performance. In addition, long-term reliability measurements were carried out to investigate the interface quality of the devices with and without gate recess. The recessfree device exhibits a smaller Vth hysteresis and a more stable performance than those of gate recessed devices. Overall, the recess-free thin barrier AlGaN/GaN MIS-HEMT demonstrates promising performance for power switching applications.