Thermo-Mechanical Reliability of Ag and Cu Joint Structure with EMC Molding

In this study, it was carried out to investigate the thermomechanical reliability in which harsh aging conditions on the EMC molded Ag sinter joint and Cu sinter joint sheet using TO-247 lead frame. To conduct thermo-mechanical reliability tests, die attached specimens were placed in an oven operated at 250 °C. Die-attached specimens were extracted at intervals of 250 h, 500 h and 1000 h to evaluate the shear strength of the EMC molded Ag sinter joint and Cu sinter joint. The Ag sintering process was realized on the TO-247 lead frame using a nano Ag porous sheet at 145 °C for 10 minutes, while the Cu sinter joint was formed using Cu paste at 250 °C for 10 min. Subsequently, the EMC molding with a post molding cure (PMC) process was carried out at 175 °C for 6 h. This study systematically investigated the thermo-mechanical reliability difference between the bonding structure between the Ag sinter joints and Cu sinter joints considering the relationship between microstructures and mechanical behaviors.