Applications of blow-up theory to thyristor turn-on

An analysis of a symmetric double-gated thyristor is performed. By further imposing that the carrier transit times depend on the drift field, we arrive at a nonlinear partial differential equation. It describes the transverse behavior and admits blow-up-type solutions leading to current filamentation, i.e., a possible explanation for hot spots. The shortening of the bases during turn-on, associated with high drift fields expanding from the central junction toward the cathode junction is also predicted. These results could provide a simple interpretation for experimental data in GTOs published by other authors.