Pre-Stress-Free Pulsed Test on Dynamic On-Resistance of High-Voltage Recessed-Gate Enhancement-Mode GaN HEMTs

The static and dynamic characteristics of a recessed-gate enhancement-mode GaN-based HEMT with a threshold voltage of approximately 2V and a current switching ratio exceeding 10⁹ were characterized. A testing environment for dynamic on-resistance was designed and constructed, double-pulse test and multi-pulse test methods. By precisely controlling the logic timing, pre-stress elimination for double-pulse test was achieved, resulting in a fast and reliable testing system with functional capabilities. Under hard switching conditions, the normalized dynamic on-resistance of the device exhibited monotonicity with increasing off-state stress, and the degree of value drift showed a strong correlation with the gate turn-on and turn-off voltage levels, as well as the duration of off-state stress. In the multi-pulse tests, the dynamic on-resistance of the device was also influenced by the number of switching cycles, switching frequency, and duty cycle.