Microscale electrohydrodynamic printing of conductive silver features based on in situ reactive inks

Electrohydrodynamic (EHD) printing is a promising approach to fabricate high-resolution features with low cost and high efficiency. However, the existing EHD printing explorations based on nano-particle inks commonly require high post-treatment temperature (4150 degrees C) to achieve desired conductivity, which limits their application in flexible substrates like polymers. Here an EHD printing strategy based on in situ reactive inks is presented to fabricate microscale conductive silver features with tunable resistance on various flexible substrates at mild temperature. The width of the EHD printed features can be flexibly tuned by process parameters, while the resistance can be tuned by the number of printing layers. The printed feature has the smallest size of 27.6 +/- 3.4 lm and exhibits an electrical conductivity of 3.3 +/- 106 S m(-1). The capability to electrohydrodynamically print microscale conductive features on various flexible substrates was finally demonstrated.