Demonstration of Low-Leakage-Current Low-On-Resistance 600-V 5.5-A GaN/AlGaN HEMT

This letter demonstrates a high-voltage, high-current, and low-leakage-current GaN/AlGaN power HEMT with HfO 2 as the gate dielectric and passivation layer. The device is measured up to 600 V, and the maximum on-state drain current is higher than 5.5 A. Performance of small devices with HfO 2 and Si 3 N 4 dielectrics is compared. The electric strength of gate dielectrics is measured for both HfO 2 and Si 3 N 4 . Devices with HfO 2 show better uniformity and lower leakage current than Si 3 N 4 passivated devices. The 5.5-A HfO 2 devices demonstrate very low gate (41 nA/mm) and drain (430 nA/mm) leakage-current density and low on-resistance (6.2 Omegamiddotmm or 2.5 mOmegamiddotcm 2 ).