3D Fine Electrothermal Modeling of IGBT Power Device for Reliability Applications

Power Modules (PM) with a standard packaging technology are subject to degradations after long operation time due to thermomechanical fatigue. Top electrical interconnections, i.e. wire bonds, are the most critical components prone to degradation leading to the device failure. Finite Element Methods (FEM) serve as a valuable tool for examining the effects of Power Module (PM) degradations through multi-physics simulations, thus they can significantly contribute to the development of semiconductor device health monitoring strategies. However, the applicability of FE models to reliability issues is conditional on their capability to yield results that accurately reflect experimental observations in degraded device conditions. This requires a well-defined electrothermal coupling that accurately represents the underlying physics, enabling the study of a wide range of degradation scenarios using a single model. In this paper, a physics-based 3D electrothermal model of an IGBT PM is developed and examined against experimental measurements in different scenarios under conduction and switching operation, to evaluate its ability to reflect experimentally observed uneven temperature fields owing to wire bonds degradations.