Integratable photodetectors based on photopolymerized conductive polymer via femtosecond laser direct writing

Conductive polymers have attracted a great deal of attention due to their remarkable electrical conductivity. However, the low solubility and inability to meet the limit for the flexible patterning fabrication ability of conductive polymers hinders their applications in miniaturized and integrated electronic devices. Here, femtosecond laser direct writing (FsLDW) is employed to achieve the in situ fabrication of polypyrrole (PPy) with flexibility. Notably, high-precision flexible patterning with a minimum feature size of 5.2 µm and spatial control over the polymerization of PPy is achieved. Moreover, PPy microwires are constructed into a photodetector that exhibits a responsivity of 644 A/W at 0.1-V bias under ultraviolet (UV) irradiation. Ultimately, an image sensor is fabricated by integrating multiple photodetectors, demonstrating the application potential of FsLDW technology for developing miniaturized and integrated electronic devices based on conductive polymers.