Investigation on the Impact of Environmental Stress on the Thermo-Mechanical Reliability of IGBTs by Means of Consecutive H3TRB and PCT Testing

During operation, power semiconductor devices are exposed to thermo-mechanical stress due to different operating points and electro-chemical stress, when operated in humid environments. So far, both stresses have been investigated separately and possible interactions of both degradation mechanisms have been neglected. In this work, the effects of previous electrochemical stress on a power device's power cycling capability, i.e. ruggedness against thermo-mechanical stress, are investigated by means of a consecutive H3TRB and power cycling test. The results of this test indicate that previous H3TRB stress indeed impacts the power cycling performance of the tested modules.