A lateral MOS controlled thyristor with shorted anode structure

A lateral MOS controlled thyristor with a shorted anode structure on an SOI (silicon-on-insulator) substrate is proposed and verified by two-dimensional numerical simulation. The shorted anode structure offers an electron extraction path from the n-base into the n⁺ anode electrode and a hole diverting path through the p⁺ cathode short during the turn-off period. The effective current gain of the parasitic short-circuit p-n-p transistor is reduced substantially by the decreased emitter injection efficiency. In addition, the modified shorted anode structure, which has the advantage of no snap-back behavior in the forward characteristics, is also presented. The simulation results show that the proposed devices improve the maximum turn-off current capability as well as the switching speed significantly with the moderate increase in forward voltage drop