| 摘要 |
PURPOSE:To make a holding current small and to make a gate current for turn-on, small by decreasing the impurity concentration of a P<2> layer so that a barrier against injected electrons in the P<2> layer is low. CONSTITUTION:An embedded type gate turn-off thyristor is composed of four layers of a P-emitter layer P1, an N-base layer N1, a P-base layer P2 and an N-emitter layer N2. A P<+> layer, whose concentration is higher than the P-base layer P2, is embedded in the P-base layer P2 and formed. A P<-> layer, whose impurity concentration is not higher than the P-base layer P2, is formed between the P-base layer P2 and the N-emitter layer N2. The maximum impurity concentration of the P-base layer P2 is made less than 5X10<17>cm<-3>. |
