Safe Operating Area of Polarization Super-junction GaN HEMTs and Diodes

This article reports safe operating area (SOA) assessment in polarization super-junction (PSJ)-based GaN high-electron mobility transistor (HEMT) and Schottky diode. The degradation physics, which limits SOA in these devices under high-voltage and high-current-injection conditions is presented. Trap-induced SOA degradation and the role of PSJ in SOA improvement are unveiled. In PSJ-field-effect transistor (FET), the impact of PSJ length and its position on SOA robustness are studied. The role of self-heating and substrate effect on degradation are discussed. PSJ diodes with different configurations of Schottky contact are investigated. The correlation between PSJ length and failure threshold is discovered, besides power and field dependence of SOA boundary. Compared with their conventional counterparts, unique failure modes are discovered in PSJ-based GaN HEMT and diode.