Electrical reliability of conductive adhesive joints: curing conditions and current density dependence

Abstract

Electronic packaging is increasingly becoming a vital part of the electronics industry, representing a key barrier to cost reduction and performance improvement. Flip-chip joining using conductive polymeric adhesives have been identified as a key technologies for future electronics assembly and manufacturing. The purpose of this study is to investigate optimum conditions to achieve the best electrical performance in conductive adhesive joints. Therefore, the quality and reliability tested in conductive adhesive joints were performed at various current densities with different curing conditions. Differential scanning calorimetry and resistance measurement were used to monitor curing condition in conductive adhesives. Accelerated life testing of conductive adhesive joints made of the selected conductive adhesive using different curing conditions was performed with various current densities. The current-induced degradation of conductive adhesive joints was investigated through optical microscope and resistance measurements. Results show a shift in contact resistance depending on curing condition and current density. The contact resistance shift is found to be due to the migration of conducting particles in the adhesive joint.