Silicon‐Rivalling Large‐Area Flexible Broadband Organic Photodetectors
Yeye Wang, Mingqun Yang, Yuyang Li, Xiaoxin Tan, Xia Zhou, Kangzhe Liu, Yunhao Cao, Feixiang Zhao, Jiayuan Zhu, Yao Li, Bingyan Yin, Jiaying Wu, Hongxiang Li, Zaifei Ma, Zheng Tang, Yanjun Fang, Xiye Yang, Fei Huang, Yong Cao, Chunhui Duan
Abstract
Abstract Organic photodetectors (OPDs) have demonstrated significant advantages as a promising next‐generation photodetection technology, especially for application in flexible and curved image sensing. However, there is still a big gap in device performance between OPDs and commercial silicon photodiodes, which hinders their practical application. Herein, using a novel near‐infrared electron acceptor featuring acceptor–donor–acceptor molecular skeleton and electron‐withdrawing cyano‐substituted terminal groups, the study reports an OPD that can fully compete with the commercial silicon photodiodes. Benefiting from the strong electron push‐pull effect and large molecular dipole moment, the OPD exhibits a broad detection range from 300 to 1100 nm and a peak external quantum efficiency of 70% at 940 nm. Moreover, owing to the reduced energetic disorder and trap density, the OPD exhibits a picoampere‐level dark current density (1.30 × 10 −10 A cm −2 ) at –0.1 V bias. Such high responsivity and low dark current density endow the OPD with a detectivity surpassing 10 13 Jones across the whole spectral range. More importantly, this superior photodetection performance can be maintained in large‐area flexible device (80 mm 2 ). These results demonstrate the huge potential of OPDs in addressing the limitations of silicon photodiodes for application in flexible and wearable electronics.