Fabrication of Cu–MWNT nanocomposite and its electrochemical migration behaviors

Metal matrix composites with multiwalled carbon nanotubes (MWNTs) are promising alternatives for stretchable and highly reliable integrated circuits in stretchable electronic systems. We investigated the electrochemical migration (ECM) characteristics of copper (Cu)–MWNT nanocomposite paste electrodes on polydimethylsiloxane. The electrodes were fabricated by screen printing using nanocomposite paste with various MWNT ratios. The ECM characteristics were assessed by water drop testing with distilled water. The results revealed that the Cu–MWNT nanocomposite electrodes containing higher MWNT ratios required longer ECM times to bridge the adjacent electrodes with ECM dendrites. The increase of the addition of MWNTs induced a slower electrochemical electrode response, thereby suppressing the ECM dendrite formation and growth. When the electrodes were stretched parallel and perpendicular to their arrangement with a tensile strain of 2 %, the ECM times decreased by around 35 % and 26 %, respectively. Different dendrite behaviors were observed with respect to the tensile direction.