Numerical stress analysis of resin cracking in LSI plastic packages under temperature cyclic loading — Part III: Material properties and package geometries

In our previous reports [1], [2], geometries of the delaminations which are most likely to lead to resin cracking in large scale integration (LSI) packages subjected to temperature cyclic loading were identified for both Cu alloy and alloy 42 leadframe packages. In this paper, assuming these delaminations, we conduct comprehensive numerical stress analysis of resin cracking to study the effect of properties of encapsulant resin and die-bonding materials and the package geometry factors. The impacts of these design parameters on resin cracking are determined and package design guide is established.