End-of-life assessment of silicon IGBT and silicon-carbide MOSFET: using the power cycling test

The power losses inside the power semiconductor device results in expanding and contracting the layers of the semiconductors with different rates. This thermal cycling is the cause of the thermo-mechanical stresses that will eventually lead to thermal fatiques, e.g. bond wire lift-off, solder cracks, and reconstruction of chip materialization. The power cycling test can replicate the thermo-mechanical stresses and is used as an accelerated end-of-life-assessment. Multple short power cycling tests are executed to find the relationship between the selected parameters and resulting thermal cycle. The thermal behaviour of the semiconductors is investigated by performing the thermal response measurements and a thermal model is derived.  Lastly, the end-of-life assessment is executed for silicon IGBTs.