Low temperature enhanced flexible conductive film by Ag flake/ion composite ink

Abstract

Poor flexibility and high contact resistance of conductive films are primary roadblock for the incorporation of Ag flake ink into practical applications. In this work, a novel and inexpensive Ag flake/ion composite ink was prepared to directly achieve the thick conductive films with excellent performances at 100 °C. The effect of Ag ion content on the resistivity and microstructures of the modified conductive film was investigated, and the flexibility and relative resistance change of the modified conductive film were measured by the cyclic bending test and compared with the traditional Ag flake ink. Consequently, the modified conductive film sintered from Ag flake/ion-0.5 in. exhibits low electrical resistivity of 4.83 × 10−5 Ω·cm, which is 42.9% lower than the Ag flake film sintered from the Ag flake ink, and the modified conductive film still displays smaller changes in resistivity and relative resistance after the cyclic bending tests. The enhanced conductivity and flexibility are attributed to the bridging effect of Ag nanoparticles (NPs) generated from the in–situ decomposition of Ag ion ink. These results demonstrate that the low-cost Ag flake/ion composite ink provides a tempting prospect for fabricating high-quality flexible printed electronics at low temperature. Keywords: Ag flake/ion composite ink, Conductive film, Flexibility, Resistivity