Fabrication of micron-SiO2@nano-Ag based conductive line patterns through silk-screen printing

Abstract

Here we present a cheap alternative for the fabrication of conductive line patterns printed on a flexible PI substrate at intermediate temperature. In order to achieve this purpose, a low-cost and water-soluble screen printing conductive paste was prepared, with micron-SiO₂@nano-Ag particles as the conductive filler. Variations in the filling content of micron-SiO₂@nano-Ag, the addition of the coupling agent, curing temperature and time can remarkably affect the electrical and mechanical performance of the conductive paste. The optimal sheet resistance (at 62 mΩ □⁻¹) and mechanical performance of the paste were achieved under the curing conditions of 140 °C for 30 min, with the filling content of 53.6 wt% of micron-SiO₂@nano-Ag (32.4 wt% of Ag) and 1.0 wt% of the coupling agent APTES. The conductive mechanism of the paste was discussed according to the “percolation theory”. The conductive line patterns fabricated through silk-screen printing were applied to be linked with a LED into a circuit, suggesting that the paste would have a potential application in electronic devices.