Laser Writing of Cu–Ag Alloy Flexible Electrodes with Excellent Oxidation and Electrochemical Migration Resistances

Bimetallic Cu–Ag conductive structures hold great promise in integrating flexible electronics, but fabrication of these structures requires complex multistep processes with poor controllability. Herein, we develop a one-step laser writing process for manufacturing the flexible Cu–Ag conductive structure from a metallic salt. The effect of laser parameters and precursor traits on the writing process, as well as the joining mechanism of Cu–Ag nanostructures, has been discussed systematically. The fabricated Cu–Ag structure not only exhibits remarkable conductivity with a resistivity of ∼8 μΩ cm but also has excellent oxidation and electrochemical migration resistances. Flexible electronic devices fabricated from these written structures, such as the flexible heater, were demonstrated as a proof of concept, thereby demonstrating excellent stability even in high-humidity-and-temperature working conditions.