Experimental Evaluation and Analysis of Dynamic On-Resistance in Hard- and Soft-switching Operation of a GaN GIT

Abstract:
In this paper, the dynamic on-resistance of a normally-off Gallium Nitride Gate-Injection-Transistor with a p-GaN gate is investigated. With the focus on the comparison between hard- and soft-switching, various operation parameters are studied, aiming to separate the impact of temperature, off-state blocking stress and switching transitions on the on-resistance. Extensive measurements are carried out in double-pulse, multi-pulse and continuous modes for hard- and soft-switching operation. Reference DC measurements are conducted to determine the effect of the device self-heating on the on-resistance. The results indicate that for the investigated transistor switching transitions aggravate the trapping effects especially at high switching frequencies, and blocking voltage shows its influence on trapping primarily in switching transitions. Soft-switching can significantly mitigate the degradation of the on-resistance.