Near-Infrared Light Photovoltaic Detector Based on GaAs Nanocone Array/Monolayer Graphene Schottky Junction

• Published in: Advanced functional materials Vol. 24; no. 19; pp. 2794 - 2800
• Main Authors: Luo, Lin-Bao, Chen, Jing-Jing, Wang, Ming-Zheng, Hu, Han, Wu, Chun-Yan, Li, Qiang, Wang, Li, Huang, Jian-An, Liang, Feng-Xia
• Format: Journal Article
• Language: English
• Published: Blackwell Publishing Ltd 01.05.2014
• Subjects: Arrays; Devices; Electric potential; Gallium arsenide; Gallium arsenides; Graphene; light trapping; monolayer graphene; Monolayers; Nanostructure; nanostructures; near infrared light; photodetectors
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201303368

Near infrared light photodiodes have been attracting increasing research interest due to their wide application in various fields. In this study, the fabrication of a new n‐type GaAs nanocone (GaAsNCs) array/monolayer graphene (MLG) Schottky junction is reported for NIR light detection. The NIR photodetector (NIRPD) shows obvious rectifying behavior with a turn‐on voltage of 0.6 V. Further device analysis reveals that the photovoltaic NIRPDs are highly sensitive to 850 nm light illumination, with a fast response speed and good spectral selectivity at zero bias voltage. It is also revealed that the NIRPD is capable of monitoring high‐switching frequency optical signals (∼2000 Hz) with a high relative balance. Theoretical simulations based on finite difference time domain (FDTD) analysis finds that the high device performance is partially associated with the optical property, which can trap most incident photons in an efficient way. It is expected that such a self‐driven NIRPD will have potential application in future optoelectronic devices. A new Schottky junction near‐infrared light photodetector is fabricated by coating a GaAs nanocone array with a monolayer graphene film, which shows high sensitivity to near‐infrared light irradiation, with good reproducibility, excellent selectivity, and rapid response speed.