Stress warpage analysis of IGBT module package reflow soldering

Abstract

In order to explore the impact of reflow soldering process on power device packaging, a 3D package model based on insulated gate bipolar transistor (IGBT) module was established using DesignModeler, and then ANSYS software was used to perform thermal-structural coupling analysis on the IGBT module, stress distribution and warpage distribution of the IGBT module were obtained by combining the unit life and death method with the solder Anand model, and finally the warpage and stress distribution of different component thicknesses were compared using the orthogonal analysis method. The results show that the warpage of the IGBT module decreases with the increase of the thickness of the substrate, increases with the increase of the thickness of the DBC copper layer, and first increases and then decreases with the increase of the thickness of the Nano silver solder layer. The thickness of the solder layer has the greatest influence on the warpage of the module, and the thickness of the Nano silver solder layer has the least influence on the warpage of the module. The parameters of each component has no major influence on the residual stress of the solder layer. After comprehensive consideration, the optimal material parameters were obtained, and the warpage results are reduced about by 77.24%, compared with the initial parameters, which provides a reference for the package design of the IGBT module.

Keywords

• insulated gate bipolar transistor module
• reflow soldering
• ansys software
• unit life and death
• warpage
• residual stress