The Role of Self-Assembled Monolayers in the Surface Modification and Interfacial Contact of Copper Fillers in Electrically Conductive Adhesives.

Printing of electrical circuits and interconnects using isotropic conductive adhesives (ICAs) is of great interest due to their low-temperature processing and compatibility with substrates for applications in sensors, healthcare, and flexible devices. As a lower cost alternative to silver (Ag), copper (Cu)-filled ICAs are desirable but limited by the formation of high-resistivity Cu surface oxides. To overcome this limitation, self-assembled monolayers (SAMs) of octadecanethiol (ODT) have been demonstrated to reduce the oxidation of micrometer-scale Cu powder particles for use in ICAs.