Finite Element Analysis of TSOP Silicon Die Crack Issue during Molding Process

摘要

In molding process, there is a step to release molded package blocks from the moulds by ejection pins. Silicon die crack failures might occur in some kind of thin small outline package (TSOP) in this mould-release step. In this work, mould-release process for a TSOP product is simulated by finite element method to clarify the mechanism of silicon die crack failures. Our analysis demonstrates that some adhesion area by organic contamination on mould inner surface, during mould-release step, may impede package block to be released smoothly from the mould, leading to locally built internal stress within silicon and causing die crack failures. Die crack risks with adhesion area in different size, shape and position are compared and high-risk conditions are defined. Die crack failure can be reduced in packages using high elastic molding compound (MC).