Effect of Interfacial Chemistry on Electrical Reliability of Copper-filled Electrically Conductive Adhesives

To investigate the effect of surface treatment agents on electrical resistivity in an 85°C/85%RH environment, copper (Cu) fillers surface-treated with oleic acid and triethanolamine were mixed with a resol-type phenolic resin to obtain the conductive adhesives. When the cured samples were exposed to 85°C/85%RH, the electrical resistivity increased significantly when oleic acid and triethanolamine were individually used for the surface treatment of the fillers. However, the increase in resistivity was greatly suppressed when these surfactants were simultaneously used for the surface treatment. This suggests that interfacial chemistry is a key for designing advanced Cu-filled adhesives.