On the Correlation Between Dynamic-QOSS and Dynamic-RON in GaN-Based HEMTs

In this brief, we investigate the correlation between dynamic-Q(OSS) and dynamic-R-ON of 650-V packaged AlGaN/GaN high-electron-mobility transistors (HEMTs). To this end, a novel measurement setup is proposed to evaluate the on-the-fly evolution of both parameters during conventional switch-mode operations. The measurements performed at V-DS= 200 V show that the dynamic-R-ON and dynamic-Q(OSS) present similar exponential transients and time constants, potentially explained by the ionization of C-related acceptors in the GaN buffer. The same activation energy (E-A) has been observed for both Q(OSS) and R-ON, suggesting that their drifts are related to the same physical mechanism. The characterization has also been performed at different V-DS levels, indicating that the observed correlation holds in the entire range up to 520 V.