Power Cycling Test Circuit for Thermal Fatigue Resistance Analysis of Solder Joints in IGBT

The paper will give a detailed presentation of an active power cycling test bench in high temperature conditions developed to ageing the solder between the Direct Copper Bonding (DCB) and the base of IGBT devices. The average junction temperature measurement protocol, the temperature regulation of the base plate, the acquisition of all the electrical signals, and the performance of the test circuit will be presented and discussed. Moreover, a thermal modelling presentation has been used to define the power cycling test parameters. The paper will present results of long time power cycling tests in server working conditions in the case of a base plate temperature equal to 90 °C, for a power injection of 300 W/cm2 during 10 s.