Comparative Investigation on the Repetitive Short-Circuit Capability of 100 V Commercial P-Gan Gate Power HEMTs with Different Processing and Structure

Reliability of 100-V p-GaN gate power high-electron-mobility transistors (HEMTs) under repetitive short-circuit (SC) stress is investigated in this work, which is a vital topic nowadays because GaN devices are quickly penetrating the medium- and low-voltage power electronics market. In this work, two devices with different processing and structure are compared. Under the stress condition of V-DD=60 V,V-GS=5.8 V, and pulse width of 10 mu s, both the devices show a certain level of degradation with positive VTH shift and current collapse, but no catastrophic failure even after 1000-cycle stress. Guidelines for under standing the failure mechanism and improving the SC capability are achieved as: 1) the floating field plate is effective to smoothen the peak electric field; 2) the extended p-GaN ledge may weaken the electric field crowding effect, reduce the hot carrier injection, and push the trapping area away from the gate area; and 3) higher gate leakage current is beneficial to suppress the positive VTH shift during the SC stress by discharging the negative charges. These guidelines are of paramount significance to promote the SC with stand capability for the p-GaN gate power HEMTs in the future.