Evaluating Local Delamination of Power Electronic Devices Through Thermal-Mechanical Analysis

Abstract

In this study, the effect of die attachment delamination on deformation of power devices during passive heating is investigated. For this purpose, Insulated Gate Bipolar Transistors (IGBT) are silver sintered with defects in their die-attachment on Printed Circuit Board (PCB) substrates. The passive heating process takes place on a hotplate under isothermal loading conditions between $50^{\circ}\mathrm{C}$ and $200^{\circ}\mathrm{C}$ while the deformation is measured optically using Digital Image Correlation (DIC) and Electronic Speckle Pattern Interferometry (ESPI). At the same time, a finite element simulation model is created with the same defect geometries and is tested for similar thermal conditions. By comparing simulation and measurement results it can be concluded that a simulative approach can deliver reliable data concerning local delamination defects. Those established methods can then be used during the quality check of devices. Optical methods will be used to filter out faulty specimens through their behavior in thermal deformation, which will be referring to the results of prior simulations.