A new lateral conductivity modulated thyristor with current saturation and low turn-off time

A new MOS-gate controlled thyristor, entitled lateral conductivity modulated thyristor (LCMT), which exhibits a high current saturation and a low turn-off time, is proposed and successfully fabricated. Experimental results show that the new LCMT achieves a current saturation capability larger than 1200 A/cm² even at high anode voltages. The forward voltage drop of LCMT is 1.2 V at 100 A/cm² where 10 V was biased to the dual gates. The turn-off time of LCMT without any lifetime-control process is 1.5 μs while that of LCMT without p+ diverter is about 2.9 μs. The p+ diverter successfully diverts holes in the drift region during the turn-off. The LCMT, where any trouble-some parasitic thyristor mechanism is eliminated, completely suppresses a latch-up and increases the maximum controllable current considerably. The proposed LCMT showed excellent current saturation characteristics at an elevated temperature and exhibited a negative temperature coefficient in high saturation current density.