Aluminium is still one of the most important contact metallisations for power electronic chips like MOSFETs or IGBTs. With a large difference in thermal expansion coefficients (CTEs) between aluminium and silicon and the temperatures generated in hot-spots during high power transients, these layers are prone to failure due to thermo-mechanical fatigue.So far, lifetime modelling was done by subjecting dedicated test specimens to the thermal cycling one would expect during normal operation. This paper will propose a novel method for creating accelerated lifetime models of thin aluminium films within the high-cycle fatigue regime by isothermal mechanical loads. The specially designed test stand is suggested to complement or replace expensive and lengthy thermal cycling and allow in-situ monitoring of failure indicators.

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