Warping model of high-power IGBT modules subjected to reflow soldering process

Abstract

High-power insulated gate bipolar transistor (IGBT) modules are the key devices for energy change and transmission. Reflow soldering process is a crucial process in IGBT module packaging manufacture. Residual stress and warpage of IGBT modules are induced after soldering, which can lead to degradation of device performance and working life. Combining frame-based baseplate and the key material properties of AlSiC at different temperatures, latent heat and viscoplastic intrinsic models of the solder, this study established a finite element (FE) model of the reflow soldering process of IGBT modules to predict the warpage and residual stresses. Reflow soldering experiments of IGBT modules were conducted to examine the shape of the lower surface of the baseplate before and after the soldering process, and are used to verify the modeling results. The model shows a good agreement with the experimental with an error of 5.46%. The FE model will contribute to the optimization of reflow soldering process and package structure of IGBT module.