Isolation structure optimization for high power reverse conducting GTO

High-power reverse conducting gate-turn-off thyristors (RC-GTOs) enable simpler circuits to be designed. However, GTO and antiparallel diode integration causes turn-off-capability degradation and undesirable GTO triggering by excess carriers flowing from the diode section. An isolation structure that uses a p-base grooving method and a selective lifetime control technique to solve this problem is investigated. A novel isolation structure that contains the drain region is also described. A high-power RC-GTO (4.5 kV, 1000 A) that is based on the optimized isolation structure is presented. The fabrication and electrical characteristics of the device are described.