Local lifetime control for enhanced ruggedness of HVDC thyristors

Abstract

Proton irradiation is experimentally demonstrated to increase the ruggedness of large area thyristors for HVDC. While maintaining very low On-state losses at VT below 1.7 V and 1.8 V for 7.2 and 8.5 kV classes (IT = 6.25 kA, T = 90 °C), record low leakage current has been achieved at 150 mm silicon wafers together with increased surge current, higher dV/dt capability and lower circuit commutated recovery time tq.