Robust Package Study for A Power Package by Simulation

Delamination and solder crack are key concerns in power package, requiring significant attention by engineers during design and process development phases to ensure lowest risk as possible. At same time, more strict requirement is addressed by customer to meet high requirements for application of automotive products. Therefore, a well understanding of factors which causes delamination and solder crack is able to drive improvements on design and process optimization for more robust package. In this study, simulation models are setup considering different factor effects on delamination and solder crack, like punch tool design and lead design to reduce stress during singulation process, and molding compound materials to minimize stress on solder during thermal cycling test (TCT). Different factor effect on stress for delamination initiation during singulation process are investigated, including lead shape, punch tip shape, punch speed, and also package orientation. Overall package stress with different EMCs are also studied to minimize stress to reduce both solder crack and delamination risk. The paper demonstrated a good case of simulation driven development.