Laser Direct Writing of Ultra-thin Ag Wires with High Conductivity for High-performance UV Photodetectors

High-conductive ultra-thin metallic wires, as basic structures in electronic devices, are highly demanded but challenging to improve the integration level and miniaturization of the devices. In this study, an efficient laser direct writing approach was proposed and aimed at preparing Ag wires with widths as narrow as 2 μm by irradiating the AgNO3-polymer film with a compact blue-violet laser. A comprehensive exploration of various parameters was conducted, leading to the optimization of Ag wires exhibiting an impressively low resistivity of 2.35×10-7Ω·m. In addition, an Ag wire prepared by laser direct writing on the flexible PEN substrate shows high tolerance to the inward and outward bending, demonstrating excellent flexibility and mechanical stability. On this basis, a UV-light detector based on the laser-irradiated interdigitated Ag patterns and sensitive CdS nanorods was demonstrated with high sensitivity and fast response.