Ultrasensitive Room Temperature Infrared Photodetection Using a Narrow Bandgap Conjugated Polymer

• Published in: Advanced science Vol. 10; no. 36; pp. e2304077 - n/a
• Main Authors: Liu, Chih‐Ting, Vella, Jarrett, Eedugurala, Naresh, Mahalingavelar, Paramasivam, Bills, Tyler, Salcido‐Santacruz, Bernardo, Sfeir, Matthew Y., Azoulay, Jason D.
• Format: Journal Article
• Language: English
• Published: Germany John Wiley & Sons, Inc 01.12.2023; Wiley Blackwell (John Wiley & Sons); John Wiley and Sons Inc; Wiley
• Subjects: blackbody; diradicals; donor–acceptor conjugated polymers; Electrons; Gallium arsenide; Graphene; high‐spin organic materials; Indium antimonide; infrared photodetectors; Mercury cadmium telluride; organic semiconductors; Polymers; Quantum dots; Semiconductors; Sensors; Spectrum analysis; Thin films; diradicals; organic semiconductors; infrared photodetectors; donor-acceptor conjugated polymers; blackbody; high-spin organic materials
• ISSN: 2198-3844; 2198-3844
• DOI: 10.1002/advs.202304077

Photodetectors operating across the short‐, mid‐, and long‐wave infrared (SWIR–LWIR, λ = 1–14 µm) underpin modern science, technology, and society in profound ways. Narrow bandgap semiconductors that form the basis for these devices require complex manufacturing, high costs, cooling, and lack compatibility with silicon electronics, attributes that remain prohibitive for their widespread usage and the development of emerging technologies. Here, a photoconductive detector, fabricated using a solution‐processed narrow bandgap conjugated polymer is demonstrated that enables charge carrier generation in the infrared and ultrasensitive SWIR–LWIR photodetection at room temperature. Devices demonstrate an ultralow electronic noise that enables outstanding performance from a simple, monolithic device enabling a high detectivity (D*, the figure of merit for detector sensitivity) >2.44 × 109 Jones (cm Hz1/2 W−1) using the ultralow flux of a blackbody that mirrors the background emission of objects. These attributes, ease of fabrication, low dark current characteristics, and highly sensitive operation overcome major limitations inherent within modern narrow–bandgap semiconductors, demonstrate practical utility, and suggest that uncooled detectivities superior to many inorganic devices can be achieved at high operating temperatures. A solution‐processed narrow bandgap conjugated polymer enables ultrasensitive infrared photodetection at room temperature. A simple, monolithic photoconductive device demonstrates a low electronic noise, enabling a detectivity of >109 Jones using the ultralow flux of a blackbody that mirrors the background emission of objects. This performance suggests practical utility, and that uncooled detectivities superior to inorganic devices are achievable at high operating temperatures.