Highly Efficient n‐Type Doped Single‐Crystalline Perylene Diimide Microwires via Solution Processing for High‐Performance Photosensors and Photo‐Neuromorphic Devices

Abstract Solution‐processed organic single‐crystal semiconductors (OSCSs) with high charge transport properties are being actively studied. However, OSCSs show relatively low intrinsic conductivity in electronic devices compared to inorganic semiconductors. This problem can be solved through doping technology applied to OSCSs. In this study, the enhancement of conductivity and photosensitivity of n‐type OSCS microwires (MWs) based on a small molecular semiconductor and an n‐type organic cationic dye‐based dopant is reported. Transmission and scanning electron microscopy show the attachment of n‐type dopants to the terrace edge of OSCS MWs, enabling rapid electron transfer and strong interaction. The n‐type doped OSCS MWs show enhanced conductivity and high optoelectronic properties, exhibiting 5,000 times improved photoresponsivity of 1.86 × 104 A W−1 compared to the OSC films fabricated…