Improving the Electrical and Mechanical Behavior of Printed Ag Microwires on Flexible Substrates by Applying High-Density Pulsed Electric Current

In order to ensure the service reliability of flexible electronic products, flexible electronic interconnection wires need to have good conductivity and good resistance and mechanical reliability. In this study, Ag microwire samples were prepared on flexible substrates by aerosol inkjet printing. The electrical tests show that the resistivity of the Ag microwire treated by high-density pulsed electric current was reduced. At the same time, the bending resistance tests show that the resistance of Ag microwire changes less when treated by high-density pulsed electric current under the same bending angle. Thus, the electrical conductivity and flexural behavior of the samples can be simultaneously enhanced by applying high-density pulsed electric current. After pulsing under the specified electrical parameters, the microstructure of the Ag microwire was denser, and the grain distribution was more uniform owing to the decrease in grain porosity, which was caused by atomic filling. The atomic diffusion was controlled directionally by the electron wind and Joule thermal effect. Ultimately, a significant accumulation of Ag atoms occurred, healing the voids and cracks. The technique holds promise for utilization in the realm of flexible printed circuits.