Silver migration control in electrically conductive adhesives

Abstract

Although conductive adhesives have been studied for many years as a lead-free alternative in electronic industry, applications of electrically conductive adhesives (ECAs) for electronic interconnect are limited to low voltage display driver devices. This is due to the serious concerns associated with the long-term reliability and high voltage application issues caused by the silver migration. In this study, a novel approach to reduce silver migration and enhance the long-term reliability of conductive adhesives is discovered by using self-assembled monolayer molecular wires. The approach enhances the long-term reliability and durability of conductive adhesives and enables the ECA for high voltage applications. In addition, the self-assembled molecular wires help the dispersion of conductive fillers (in particular, nano-sized (<100 nm) conductive fillers) in the polymer matrix and enhance the electrical conductivity of conductive adhesives. Due to the high current density of those functional molecular monolayers, the current carrying capability of conductive adhesives can also be improved significantly