Contents I. Introduction
Printed electronics have received considerable attention in recent years due to their low cost compared to electronics prepared using the conventional vacuum fabrication process [1]–[3]. The introduction of traditional printing concepts into electronic manufacturing can dramatically reduce manufacturing cost because it eliminates the need for a high vacuum. In addition, unlike vacuum-based processes such as sputter deposition or chemical vapor deposition (CVD), solution-based printing and inkjet printing, in particular, can effectively reduce material waste, making printing a more environmentally friendly approach. Furthermore, printing methods are compatible with the high-throughput roll-to-roll process, making it possible to achieve large-area flexible devices [2]. Several printing techniques have been developed, including inkjet printing [3], [4], spray printing [5], screen printing [6], gravure printing [7], offset printing [8], laser printing [9], and slot-die coating [10]. As printed electronics have rapidly expanded, new materials suitable for printing have been developed, including silver (Ag) nanoparticle ink for printed electrodes and interconnected wires [11]. To improve the patterns obtained by printing, Ag nanoparticle ink is modified with organic functional groups. Hence, to print Ag circuits or electrodes, annealing is required to break the connections between the organic groups and nanoparticles, which increases the conductivity [12]. The annealing process commonly involves long-term heating, which results in two critical drawbacks: long-term heating is not suitable for flexible plastic substrates and the annealing time is too long for application in industrial roll-to-roll processes.
