Electrochemical assembly of SAM on copper for epoxy/copper adhesion improvement

This paper reports on adhesion enhancement effects of self-assembled organothiol treatment on copper/epoxy interface, as well as a significant reduction in treatment time by the electrochemical assembly approach. Interfacial adhesion strength between copper/epoxy interfaces was studied against different treatment time under the influence of electrical potential. A maximum 20-fold enhancement was demonstrated through improved chemical linkage formed between copper substrate and epoxy layer. The treatment time was also reduced by 32 times to 1800s with the proposed preparation method. Electrochemical characterization including electrochemical impedance spectroscopy (EIS) was carried out in this work. Results were correlated with adhesion enhancement effect by organothiol self-assembly monolayer (SAM). The double layer capacitance model was used to explain how molecular film formation process affects adhesion results between Cu/epoxy interfaces.