High-Temperature Static and Dynamic Characteristics of 4.2-kV GaN Super-Heterojunction p-n Diodes

This article presents the static and dynamic characterization of 4.2-kV super-junction p-n diodes at high temperatures. Reduction of the forward current with increasing temperature is consistent with 2DEG mobility degradation caused by polar optical phonon scattering. Reverse leakage current was dominated by isolation leakage, with an activation energy of ~0.26 eV, close to the reported activation energy of surface leakage. Dynamic switching characterization in the temperature range from room temperature (RT) to 300 °C showed a nonmonotonic dependence of dynamic ON-resistance on temperature. At room temperature and 50 °C, devices showed zero current collapse (CC) up to OFF-state stress bias of 3 kV at 100
$\mu \text{s}$
timescale. Between 100 °C and 200 °C, significant CC was observed. From 250 °C to 300 °C, devices showed recovery from the severe CC. The degradation and recovery of dynamic ON-resistance can be explained by emission and recapture of holes during the OFF- and ON-states, respectively.