Electromigration Induced Break-up Phenomena in Liquid Metal Printed Thin Films

Room temperature liquid metal (RTLM)-related electronics has recently been found increasingly important in a wide variety of emerging areas. In particular, printable liquid metal ink opens the way for direct writing of electronics spanning form microscale to even nanoscale. However, such fluid-like circuits also raised important fundamental as well as practical issues for solving. A big issue facing its future large-scale application is that the failure features of the conductive wires under electrical current densities are not clear. Here, we discovered for the first time that a liquid metal thin film would be broken by the so-called electromigration effect as the applied current increases to a critical magnitude. A theoretical model was established to preliminarily interpret the phenomena and the related effects. The break-up effect in the liquid metal-based circuits could be one of the major hurdles that must be tackled with caution in the research and application of future liquid metal technologies, especially for the printed microelectronics thus enabled.