Operation Range-Optimized Silver Nanowire Through Junction Treatment

In past decades, stretchable conductors have been investigated for a wide range of applications, and the operation strain range of such devices varies by application. To commercialize stretchable devices, it is necessary to optimize the deformation of stretchable electrodes based on a given device elongation range. Therefore, we investigated the deformation mechanics of a silver nanowire (AgNW) electrode on an elastomeric substrate depending on its junction treatment method. At low-strain (  20%), the thermally annealed AgNW electrode rapidly increased in resistance, while the laser-welded AgNW electrode showed lower resistivity change. By in situ surface analysis and a repetitive tensile test, we observed that the thermally annealed AgNW electrode shows less cracking at low strain but the laser-welded AgNW electrode exhibits fracturing of individual nanowires at low strain. Furthermore, at high strain, laser-welded AgNWs could slide to reduce stress during elongation, resulting in a smaller change in resistance compared to that of thermally annealed AgNW electrode. These results indicate that optimization of adhesion is necessary to fabricate stretchable devices based on deformation range.