Cryogenic operation of emitter switched thyristor structures

This paper analyses the effect of decreasing the operating temperature on t he electrical characteristics of 1100 V epitaxial EST structures. Detailed performed static and transient measurements on ceramic packaged devices at 77 K have shown a significant increase of the maximum controllable current density and a notable reduction of the transient losses and the turn-off ti me. A reduction of the on-state voltage drop with temperature is observed a t current density values higher than 80 A/cm(2) (positive coefficient), lea ding to a more uniform turn-off process. Furthermore, a model is provided t o include the temperature effect on the latching current of the main and pa rasitic thyristor, transconductance and dynamic parameters. (C) 1999 Elsevi er Science Ltd. All rights reserved.