Highly Sensitive and Broadband Organic Photodetectors with Fast Speed Gain and Large Linear Dynamic Range at Low Forward Bias |
| |
| Authors: | Riming Nie Xianyu Deng Lei Feng Guiguang Hu Yangyang Wang Gang Yu Jianbin Xu |
| |
| Affiliation: | 1. Research Center for Advanced Functional Materials and Devices, Shenzhen Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen, P. R. China;2. Cbrite Inc. 421 Pine Avenue, Goleta, CA, USA;3. Department of Electronic Engineering and Materials Science and Technology Research Centre, The Chinese University of Hong Kong (CUHK), Shatin, Hong Kong, China |
| |
| Abstract: | Photodetectors with high photoelectronic gain generally require a high negative working voltage and a very low environment temperature. They also exhibit low response speed and narrow linear dynamic range (LDR). Here, an organic photodiode is demonstrated, which shows a large amount of photon to electron multiplication at room temperature with highest external quantum efficiency (EQE) from ultraviolet (UV) to near‐infrared region of 5.02 × 103% (29.55 A W?1) under a very low positive voltage of 1.0 V, accompanied with a fast response speed and a high LDR from 10?7 to 101 mW cm?2. At a relatively high positive bias of 10 V, the EQE is up to 1.59 × 105% (936.05 A W?1). Inversely, no gain is found at negative bias. The gain behavior is exactly similar to a bipolar phototransistor, which is attributed to the photoinduced release of accumulated carriers. The devices at a low voltage exhibit a normalized detectivity (D *) over 1014 Jones by actual measurements, which is about two or three order of magnitudes higher than that of the highest existing photodetectors. These pave a new way for realization of high sensitive detectors with fast response toward the single photon detection. |
| |
| Keywords: | bipolar phototransistors bulk‐heterojunction photodiodes photoelectronic multiplication organic electronics |
|
|
