Lateral AlGaN/GaN power diode with MIS-Gated hybrid anode for ultra-low turn-on voltage and high breakdown voltage

Abstract

In this letter, a novel AlGaN/GaN lateral power diode featuring a recessed Metal/Al2O3/ III-Nitride (MIS) Gated-hybrid-anode (MG-HAD) was experimentally demonstrated. The unique Gated-hybrid-anode design and accordingly the new current conduction mechanism enable the MG-HAD to deliver ultra-low forward turn-on voltage (VT) and reverse leakage for lowering the power consumption of the device. The typically ultra-low turn-on voltage of 0.3 V is obtained in the MG-HAD improved by 67 % compared with the fabricated-conventional AlGaN/GaN SBDs. Moreover, the ultra-low VT exhibits good uniformity with the minimum and maximum VT of 0.2 and 0.55 V, respectively. To the best of our knowledge, 0.2 V is the lowest VT of GaN power diodes up to date. On the other hand, a high breakdown voltage of over 1.1 kV at respectably low leakage current of 1 μA/mm was obtained in the proposed MG-HAD with anode-to-cathode spacing (LAC) of 20 μm. Besides the superior device performance, the proposed diode is fully-compatible with normally-off AIGaN/GaN MISFETs, which establish a basis for high-speed and high-efficiency full-GaN single-chip power ICs.