Comportement homogénéisé d'un microvia pour la modélisation mécanique d'un circuit imprimé avec composants enfouis

The boom of the e-technology is leading to new designs for printed circuit boards in response to the increase in component density. The solution found is to integrate active components into the unoccupied volume of the printed circuit board. To estimate the printed circuit board life time, the response of the interconnection layer to thermo-mechanical loads is studied. In fact, this area is prone to various failures. As this kind of design with microvias interconnected chips become usual in industry, the large number of microvias present can be managed by a finite element software. To overcome this problem, a numerical homogenization is implemented to replace the microvia with its homogeneous equivalent material in large printed circuit board structure. This work also highlights the accuracy of the average response of the homogeneous equivalent material but also the necessity to keep at least a fully detailed unit cell to analyze the local stresses. This will enable the detection of crack initiation zones in microvia interconnect layers.