Dynamic on-state resistance instability characterization of a multi-chip-GaN MIS-HEMTs cascode power module

The dynamic on-state resistance instability of a high-current cascode multi-GaN-chip power module under high frequency and voltage switching conditions is demonstrated in this paper. The presented double pulse test topology is utilized to evaluate switching dependencies on voltage, current, and frequency, showing its versatility in investigating the switching instability of the device. The extended defects in the buffer layer resulted in a decrease in dynamic on-state resistance (R_DS-ON) under hard switching conditions. Despite this, no noticeable R_DS-ON degradation occurs under harsh switching conditions due to electron de-trapping. This study comprehensively analyzes the dynamic stability of a multi-GaN-chip cascode module with devices.