Highly Efficient Full van der Waals 1D p‐Te/2D n‐Bi2O2Se Heterodiodes with Nanoscale Ultra‐Photosensitive Channels

• Published in: Advanced functional materials Vol. 32; no. 30
• Main Authors: Wang, Weijun, Meng, You, Wang, Wei, Zhang, Zhuomin, Xie, Pengshan, Lai, Zhengxun, Bu, Xiuming, Li, Yezhan, Liu, Chuntai, Yang, Zengbao, Yip, SenPo, Ho, Johnny C.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.07.2022
• Subjects: Bias; heterodiode; Heterostructures; Materials science; Miniaturization; Photodiodes; Photoelectricity; Photosensitivity; Photovoltaic cells; self‐powered photodetection; Semiconductor devices; superlinearity; Te/Bi 2O 2Se
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202203003

Continuous miniaturization of semiconductor devices is the key to boosting modern electronics development. However, this downscaling strategy has been rarely utilized in photoelectronics and photovoltaics. Here, in this work, a full‐van der Waals (vdWs) 1D p‐Te/2D n‐Bi2O2Se heterodiode with a rationally designed nanoscale ultra‐photosensitive channel is reported. Enabled by the dangling bond‐free mixed‐dimensional vdWs integration, the Te/Bi2O2Se type‐II diodes show a high rectification ratio of 3.6 × 104. Operating with 100 mV reverse bias or in a self‐power mode, the photodiodes demonstrate excellent photodetection performances, including high responsivities of 130 A W−1 (100 mV bias) and 768.8 mA W−1 (self‐power mode), surpassing most of the reports of other heterostructures. More importantly, a superlinear photoelectric conversion phenomenon is uncovered in these nanoscale full‐vdWs photodiodes, in which a model based on the in‐gap trap‐assisted recombination is proposed for this superlinearity. All these results provide valuable insights in light–matter interactions for further performance enhancement of photoelectronic devices. 1D p‐Te/2D n‐Bi2O2Se heterodiodes with rationally designed nanoscale ultra‐photosensitive channels are fabricated via dangling bond‐free mixed‐dimensional van der Waals integration. Except for the excellent photodetection performance, the type‐II diodes exhibit a superlinear photoelectric conversion phenomenon, with a model based on the in‐gap trap‐assisted recombination proposed for this superlinearity.