Ag Nanoparticle Ink for High-Resolution Printed Electrodes and Organic Thin-Film Transistors Using Reverse-Offset Printing

Reverse-offset printing is capable of ultrafine printing at the submicron scale and may be applied to the fabrication process of electronic devices. In this study, the composition of Ag nanoparticle ink is investigated suitable for reverse-offset printing using Ag nanoparticles synthesized by a thermal decomposition method via oxalate-bridging silver alkylamine complexes. The suitability of Ag nanoparticle ink for the blanket is considered while focusing on the absorption characteristics, wettability, and drying properties. Using the synthesized Ag nanoparticle ink, the reverse-offset printing conditions are optimized, successfully forming submicron-scale ultrafine patterns. The successful fabrication of fully printed organic thin-film transistors (TFTs) is also achieved with a significantly short (1 µm) channel using reverse-offset printing. A maximum mobility of 1.25 cm² Vs⁻¹ at an operating voltage of less than 5 V is achieved in the printed organic TFT with a 5-µm channel.