Water Transfer Printing of Multilayered Near‐Infrared Organic Photodetectors

Abstract To obtain high‐performance organic near‐infrared (NIR) photodetectors, it is essential to suppress the noise current. Here, high‐performance organic NIR photodetectors based on a multilayered structure fabricated by a water transfer printing strategy are reported. These devices comprise a NIR small molecule electron‐accepting layer (IEICO‐4F) and several repeating polymers stacked electron‐donating layers (PTB7‐Th). These polymer layers are prepared onto water substrate and transferred to the target substrate directly, working as an electron‐donating moiety and also as an electron blocking layer. The water transfer printing fabricated multilayered NIR photodetectors obtain extremely low noise current by suppressing the reverse dark current and decreasing the carriers trapping/de‐trapping. The NIR organic photodiodes with multilayered structure exhibit a noise current as low as about 27 fA Hz − 1/2 at − 0.5 V, resulting in a specific detectivity of approaching 10 12 Jones at the NIR wavelength of 860 nm that is about 3 orders of magnitude higher than that of the control devices with a bulk‐heterojunction structure. Furthermore, the multilayered NIR photodetectors also exhibit a large linear dynamic range, fast response simultaneously. This proposed multilayered structure and the utilization of the water transfer printing method could help create high‐performance organic photodetectors.