Low switching loss, high power gate turn-off thyristors (GTOs) with n-buffer and new anode short structure

6000-V gate-turn-off thyristors (GTOs) were developed for high-voltage power converters. In order to attain a high blocking voltages simultaneously with low turn-on and turn-off switching losses, a combination of an n-buffer layer and a cylindrical-anode short structure was implemented. This structure is effective in sweeping away excess carriers during turn-off transient without increasing the on-state voltage. The device, fabricated on a 33 mm diameter wafer, can turn off an anode current greater than 700 A at a junction temperature of 125 degrees C.