Thermal stress and mechanical strain real time mapping in Intelligent Power Switches device

Thermal stress and mechanical deformations are the principal causes of power devices premature failures, especially in those critical conditions where they work under repetitive high current pulses or during overloads. Currently, a large effort has been devoted, both in experimental and computer modeling techniques, to predict the lifetime of those power devices used in automotive applications where high reliability is mandatory. Moreover, the knowledge of the thermal and mechanical stress, during the operations, could allow an effective refining of the design rules to improve devices reliability. In this paper, a novel technique to experimentally measure both thermal and mechanical fatigue on IPSs (Intelligent Power Switches) is presented.