Proof-of-Concept for an On-Chip Kelvin-Emitter RTD Sensor for Junction Temperature Monitoring of IGBTs

This paper presents the use of an on-chip Kelvin-Emitter Resistor to monitor the junction temperature of an IGBT during converter operation. The Kelvin-Emitter Resistor is manufactured using a 250μm Aluminium Nitride substrate with a Platinum resistive trace. The resistor is mounted directly on the Emitter surface metallization using conductive epoxy and is evaluated by injecting a small sensing current between the Power-Emitter and Kelvin-Emitter terminals during the on-state of a 600V/75A IGBT. The IGBT is operated in a single-phase inverter and the measured temperature is compared to measurements made using an optical fibre, an Infra-Red Camera, and the VCE(T) method.