Adhesion improvement of thermoplastic-based isotropic conductive adhesives under humid environment using self-assembled monolayer compounds

The adhesion properties of poly(arylene ether) (PAE-2), a thermoplastic, based isotropic conductive adhesive (ICA) materials were investigated. PAE-2-based ICAs, as well as epoxy-based ICAs (thermosets), showed a dramatic reduction in adhesion to a NiAu surface during the 85 °C/85% RH aging test. Self-assembled monolayer (SAM) molecules were introduced to the interface between the PAE-2-based ICA and the metal bond pad to increase the adhesion strength during the aging test. By depositing SAMs on the NiAu surface, the adhesion strength after aging was significantly improved. Finally, the SAM treatment on NiAu surface did not adversely affect the contact resistance stability.