New Process of Self-Organized Interconnection in Packaging Using Conductive Adhesive with Low Melting Point Filler

Abstract

A model experiment of the novel self-organized joining process using conductive adhesive with low melting point alloy was demonstrated to break through the limitation of conventional solders and adhesives used in electronics packaging. Basic properties of the adhesive paste, joint morphology, the formation of the conduction path, and the self-organization characteristics were examined. Melting fillers were preserved in their initial spherical form in resin without oxygen-reduction capability, although enlargement of the alloy domain occurred in the case of oxygen-reduction polymer. The formation of the conduction path could be controlled accurately by varying the resin performance and the process parameters such as the gap distance of the joint and the volume fraction of filler. Self-organization due to capillary wetting of melting alloy was observed on the copper-line-patterned glass-epoxy substrate. The pair of lines on the faced substrates was selectively interconnected with an alloy joint.