High-Performance Ultrathin-Barrier AlGaN/GaN Hybrid Anode Diode With Al₂O₃ Gate Dielectric and In Situ Si₃N₄-Cap Passivation.

In this article, an ultrathin-barrier (UTB) AlGaN/GaN diode featuring metal–insulator–semiconductor (MIS)-gated hybrid anode (MG-HAD) and in situ Si₃N₄ cap passivation is demonstrated. The intrinsic turn-on voltage (V_ON) as low as 0.31 V determined by the as-grown AlGaN-barrier thickness (4.9 nm) is obtained and the V_ON exhibits excellent uniformity. More importantly, benefit from the MIS-gated hybrid anode structure, the UTB MG-HAD features good thermal stability in reverse blocking capability. The device delivers a substantially low leakage less than 1~μm/mm at −300 V at high temperature (HT) up to 200 °C, which is more than 100 × lower than that in the reference device w/o gate dielectric. Besides, the device exhibits respectably improved dynamic characteristics due to the incorporation of in situ Si₃N₄-cap passivation layer and remote plasma pretreatment (RPP) prior to Al₂O₃ gate dielectric deposition. The UTB MG-HAD featuring precisely V_ON modulation and low reverse leakage is of great interest for power electronic applications. [ABSTRACT FROM AUTHOR]