The project focuses on the use of the laser reflectometry technique, usually employed for studying thin films, in an innovative way: conduct thermoreflectance measurements to determine directly the junction temperature of an IGBT module short-circuited. The thermoreflectance measurement, a non-destructive and non-contact technique, consists in employing a laser beam and measuring the reflected light, whose amplitude changes as the temperature of the DUT. Therefore, it is possible to relate the measured light with the temperature.
The junction temperature is a key parameter to study the reliability of an IGBT module under thermal stresses during operation.