Investigation of collector emitter voltage characteristics in thermally stressed discrete IGBT devices

Discrete package Insulated Gate Bipolar Transistor (IGBT) devices are a popular choice for low-medium power converters. Although IGBT power modules have been extensively studied in literature, there exists a major gap for reliability study particularly for discrete devices. Current failure diagnostic tools are not mature enough for failure diagnosis and prognosis in real-time operation based on system condition monitoring. In order to move power conversion technologies forward reliably, this paper investigates the changes in on-state collector-emitter voltage drop (V_ce,_on) of discrete IGBT devices exposed to thermal cyclic stress. Depending on the dominant aging mechanisms and device structure, V_ce,_on variation trend is different. In this paper, V_ce,_on variations of three different IGBT device types, namely, punch through, non-punch through and field stop, are continuously monitored during accelerated aging tests, and their relations to aging mechanisms are identified.