Performance of Recessed Anode AlGaN/GaN Schottky Barrier Diode Passivated With High-Temperature Atomic Layer-Deposited Al2O3 Layer

Abstract

We have proposed a method of surface passivation with high-temperature atomic layer-deposited (ALD) Al2O3 layer on the fully recessed anode AlGaN/GaN-based Schottky-barrier diode (SBD) and systematically analyzed the cause of the lateral and the vertical leakage component in the SBD. The forward turn-on voltage of the recessed SBD decreased to 0.38 V from the value of 0.8 V of the nonrecessed SBD due to the lowered barrier height. Application of the ALD Al2O3 surface passivation layer to the recessed SBD, which was deposited at higher temperature (550 degrees C), significantly improved the performances of the proposed SBD such as high on-current of 12 A at 1.5 V and increased breakdown voltage of 780 V with greatly decreased reverse leakage current (at least 3 orders lower inmagnitude), compared to the correspondingon-current of 6 A at 1.5 V and breakdown voltage of 510 V of the reference SBD.