Investigation into the impact of bulk defects in drift layer on the electrical properties for GaN-based trench Schottky barrier diodes

Abstract By using numerical simulation tools, this work has systematically investigated the impact of bulk defects in the drift layer on GaN-based trench MIS barrier-controlled Schottky (TMBS) rectifiers. Investigations show that in the forward conduction, the acceptor-type defects significantly increase the on-resistance (Ron.sp). When the device is in reverse blocking mode, donor-type defects tend to weaken the charge-coupling effect, leading to early breakdown of the device, while acceptor-type defects show the opposite feature. In addition, our report identifies that the reverse blocking effect is significantly impacted when the position for the defects is located in the region with maximum electric field magnitude. We also find that the acceptor-type traps will generate remarkable charging/discharging effect, which will destabilize the dynamic forward conduction process. Hence, we numerically prove that bulk defects shall be avoided in actual power diodes.