Abstract: Based on a short anode GTO structure (SA-GTO),a novel GTO structure called an injection efficiency controlled gate turn off thyristor (IEC-GTO) is proposed,in which the injection efficiency can be controlled via an additional thin oxide layer located in the short anode contact region.The forward blocking,conducting,and switching characteristics are analyzed and compared with an SA-GTO and conventional GTO.The results show that the IEC-GTO can obtain a better trade-off relation between on-state and turn-off characteristics.Additionally,the width of the oxide layer covering the anode region and the doping concentration of the anode region are optimized,the process feasibility is analyzed,and a realization scheme is given.The results show that the introduction of an oxide layer would not increase the complexity of process of the IEC-GTO.

Key words: power semiconductor devices, gate turn-off thyristor, injection efficiency