Electrical sintering characteristics of inkjet-printed conductive Ag lines on a paper substrate

The electrical sintering characteristics of inkjet-printed line patterns on a paper substrate were investigated by varying initial pattern resistance, input voltage, sintering time, and input voltage profile. The initial resistance was controlled by preheating the patterns, and its range was between 500 Ω and 5 MΩ. Depending on the input voltage and initial resistance, there exist three different regions: sintering, no change, and blowout. While no sintering is observed for too high initial resistance, blowout of printed lines occurs for a larger input voltage. For the initial resistance lower than ~ 100 kΩ and the input voltage ranging from 20 V to 40 V, all the printed lines are electrically sintered within a short time without damaging the underlying paper substrates. When using the two-step voltage profile, the final resistance of lines becomes five times smaller than the resistance with the one-step voltage profile due to the increase in the grain size and the reduction in the void area, and no burning or blowout occurs in the lines. Due to its many advantages, the electrical sintering can provide a fast, reliable and effective way to fabricate high quality inkjet-printed conductive patterns for various printed electronics applications.