Modelling the reliability of high-density substrates and associated microelectronic components

Abstract

This paper presents lifetime predictions, based on Finite Element Analysis (FEA), for the copper via connectors present in High Density Interconnectors (HDI) used for mounting of CSP's. The life-saving impact of various fillings of these connectors is investigated using different FEsub-models for capturing the intricate HDI substructure. A ranking of the impact on lifetime of the various fillings is presented. Moreover, the structural integrity of the solder bumps of a flip chip structure with and without underfill is examined using FE. It is demonstrated analytically that the underfill may lead to an improvement in lifetime of 300% and more.