Light on Failures: Red-der than Red

The commercialization of various product categories requires compliance with quality standards defined at both national and international levels. Within the scope of electronic device qualification, reliability represents a fundamental parameter. This aspect is particularly critical for new power devices based on Silicon Carbide (SiC) and Gallium Nitride (GaN), whose failure mechanisms are still less understood compared to those affecting Silicon devices. In this work, two light-based technologies are proposed for the study of aging in two different types of devices. Specifically, an infrared camera was used to evaluate the surface temperature reached by devices stressed by a current pulse under operating conditions. The heat generated by the Joule effect, which causes the temperature rise, induces thermomechanical deformations analyzed by means of a red laser interferometric system. This study correlates the electrical, thermal, and thermomechanical behavior of the devices and their variation as a function of aging, shedding light on failure mechanisms and enabling more precise estimates of remaining useful life.