The Temperature Dependence of the Flatband Voltage in High Power IGBTs

This letter experimentally demonstrates the temperature dependence of the Flatband Voltage (VFB) in high power Insulated-Gate-Bipolar-Transistors (IGBTs). The gate voltage during the turn-on delay is shown to fluctuate up to 5mV/°C as a result of this temperature dependence. We investigate the practical use of this temperature dependence as an addition to the genre of IGBT junction temperature measurement methods known as Temperature Sensitive Electrical Parameters (TSEPs). The letter will outline some possible measurement circuits and highlights issues with the VFB that may make its use as a TSEP problematic.