Numerical Study of a Thyristor Injection Insulated Gate Bipolar Transistor (TI-IGBT) Using P-N-P Collector

A new thyristor injection concept is proposed to decrease conductivity modulation effects in an Insulated Gate Bipolar Transistor (TI-IGBT), which adds a floating p-type layer and an n-type layer at the collector side. The additional p-layer and n-layer form a parasitic n-p-n transistor to reduce the hole injection efficiency though the potential difference between the floating p-type layer and the field stop (FS) layer, as well as decrease hole concentration near the collector, turn-OFF fall time and turn-OFF loss. TACD simulations shows, a 24% and a 10% reduction in turn-OFF fall time and turn-OFF loss are respectively obtained in the proposed TI-IGBT with the similar breakdown voltage and threshold voltage compared to a conventional FS-IGBT by the potential difference with the various floating p-layer doping. Therefore, the TI-IGBT offers a competitive option for high power converter applications.