Thermal-Mechanical FE Analysis of IGBT Module with Different Power Terminal Shape

The temperature cycling (TC) test is a basic experiment for the IGBT module to assess the reliability, which can effectively expose the existing problems in the package of device. A finite element model with three shapes of power terminals is established to investigate the deformation and stress distribution of the IGBT module. The results show the power terminal with an intermediate bending has a maximum deformation while the load distribute is more uniform. The nodal force disequilibrium coefficient of the four fillets with an intermediate bending is less than 12% in the X direction and Y direction while the other two power terminals over 20.5%. The maximum equivalent stress of the power terminal resulted from the FEA are 140MPa, 159MPa and 168MPa, the stress level of power terminal with an intermediate bending is significantly lower than the other shapes.