TCAD simulation of current filamentation in adjacent IGBT cells under turn-on and turn-off short circuit condition

摘要

In order to reveal cause-effect relationship between collector-side electric field strength (E-collector) and onset of current filaments under short circuit, a 33 kV trench IGBT was investigated by TCAD simulation. It is shown that during short circuit turn-on, current filamentation is triggered by avalanche generation at the collector side, due to high E-collector that aroused from low hole injection. During the short circuit turn-off, filaments are induced by avalanche at emitter side. As a consequence, E-collector increases in the cell exhibiting current filamentation. The paper also proposes a thorough analysis of the evolution of the filaments in time. (C) 2015 Elsevier Ltd. All rights reserved.