High Speed Photodetector Based on 2D Organic/Inorganic Hybrid Van Der Waals Heterostructure Devices

Abstract

Abstract 2D van der Waals (vdWs) heterostructure photodetectors have captured significant interest for their ability to achieve substantial optical conductivity gain and device tunability. However, the light absorption in ultrathin 2D inorganic vdWs devices is generally weak that leads to low detectivity. In addition, the intrinsic defects in 2D semiconductors cause significant carrier trapping and scattering by defect states during the transport process, which seriously restricts the response speed of the device. In this paper, a molybdenum tungsten disulfide (Mo 0.1 W 0.9 S 2 ) is used to replace the conventional 2D semiconductor, while the light absorption efficiency of the device is significantly enhanced by the adoption of N’‐ Dimethyl‐3,4,9,10‐perylenedicarboximide (Me‐PTCDI), thus achieving both fast response and high detectivity. A series of type‐II organic/inorganic hybrid vdWs heterostructure photodetectors is systematically investigated based on Me‐PTCDI and Mo 0.1 W 0.9 S 2 . In particular, the device incorporating monolayer (ML) Me‐PTCDI and few‐layer (FL) Mo 0.1 W 0.9 S 2 demonstrates a detectivity of up to 4.4 × 10 11 Jones and a response time of 24.9 µs. By utilizing the device as a light sensing pixel, a single‐detecting pixel imaging system is demonstrated with high precision, showcasing promising prospects in fast imaging applications.