Wenkai Zhu; Faguang Yan; Quanshan Lv; Ce Hu; Kaiyou Wang
Abstract
Photodetectors based on two-dimensional (2D) materials and their heterostructures have been attracting immense research interests due to their excellent device performances, such as ultrahigh photoresponsivity, ultrafast and broadband photodetection, polarized sensitivity, flexibility, and Complementary ...
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Photodetectors based on two-dimensional (2D) materials and their heterostructures have been attracting immense research interests due to their excellent device performances, such as ultrahigh photoresponsivity, ultrafast and broadband photodetection, polarized sensitivity, flexibility, and Complementary Metal-Oxide-Semiconductor (CMOS) compatibility. Here, we firstly compare the device performance of several photodetectors based on Schottky junctions and p-n junctions, such as photoresponsivity and response time. Then, we provide an overview of the recent progress on 2D material-based photodetectors, emerging strategies to improve device performances by structure optimization and bandgap engineering as well. Finally, we discuss the challenges and perspectives on the exploration of 2D materials and their heterostructures for future application in electronics and optoelectronics.
Wenkai Zhu; Faguang Yan; Xia Wei; Quanshan Lv; Huai Yang; Kaiyou Wang
Abstract
Two-dimensional (2D) atomic crystals, such as graphene, black phosphorus and transition metal dichalcogenides (TMDCs) are attractive for use in optoelectronic devices, due to their unique optical absorption properties and van der Waals (vdWs) force between layers. Heterostructures based on layered semiconductors ...
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Two-dimensional (2D) atomic crystals, such as graphene, black phosphorus and transition metal dichalcogenides (TMDCs) are attractive for use in optoelectronic devices, due to their unique optical absorption properties and van der Waals (vdWs) force between layers. Heterostructures based on layered semiconductors provide a new platform for broadband high-performance photodetectors. In this work, graphene-MoTe2-WS2-graphene vdWs heterojunctions are fabricated for photodetection. The fundamental electric properties and the band structures of the heterojunctions are investigated and discussed. The devices show a high responsivity (≈ 140 mA W -1 at 825 nm), stable and broadband photodetection from UV to NIR wavelength range (300 - 1350 nm), fast response time of 186 µs and self-driven photodetectors. The scanning photocurrent microscopy maps are also employed to study the mechanism of photocurrent generation in the heterojunction. Our results reveal that the vdWs heterojunctions with graphene electrodes offer a new route to broadband detection, optical communication and energy harvesting applications.