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

We have proposed a method of surface passivation with high-temperature atomic layer-deposited (ALD) Al
₂
O
₃
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 Al
₂
O
₃
surface passivation layer to the recessed SBD, which was deposited at higher temperature (550 °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 in magnitude), compared to the corresponding on-current of 6 A at 1.5 V and breakdown voltage of 510 V of the reference SBD.