Precise Determination of Dynamic RDSon in AlGaN/GaN Power HEMTs under Soft Switching Condition

Abstract:
The dynamic on-state resistance RDS,on phenomenon is a key challenge in AlGaN/GaN high electron mobility transistors (HEMTs) for high efficient power conversion. The increase of the on-state resistance is not only leading to increased losses, but also represents a reliability risk for power conversion systems. In this paper, a setup for high switching speeds in a pulsed I-V configuration is presented. Investigations in off-state preconditioning time and repetitive measurements are performed for both Schottky and ohmic p-GaN enhancement type devices. The results illustrate that the dynamic RDS,on features different tendencies depending on the applied conditions. At high bias and long off-state time, no increase of RDS,on is observed. The maxima of RDS.on are found at different drain bias for Schottky p-GaN devices and gate injection transistors (GITs).