A new trench gate accumulation mode field effect emitter switched thyristor

A new trench gate Emitter Switched Thyristor (EST) structure using an ACCUmulation mode Field Effect Transistor (ACCUFET) is reported for the first time. In this new trench gate EST, the series MOSFET can be designed to have a higher channel density than the conventional trench EST due to the absence of the P⁺ base region resulting in forward voltage drops equal to thar of thyristors and MOS-controlled thyristors. Moreover, the integration of the ACCUFET into the thyristor structure completely eliminates the parasitic thyristor that is inherent in the conventional EST, higher maximum controllable current for ESTs. The on-state and turn-off characteristics of 600-V forward blocking trench ESTs obtained from two dimensional numerical simulations are described and compared with those of the trench IGBT and MCT. Numerical simulations with resistive loads indicate comparable turn-off times for the trench EST, when compared with IGBTs and MCTs