Schottky-Contacted WSe 2 Hot-Electron Photodetectors with Fast Response and High Sensitivity

作者：Mingliang Zhang, Xingqiang Liu, Xinpei Duan, Sen Zhang, Chang Liu, Da Wan, Guoli Li, Zhenhai Xia, Zhiyong Fan, Lei Liao · 发表于：ACS Photonics · 年份：2021 · DOI：10.1021/acsphotonics.1c01256 · 被引用次数：25 · 研究领域：2D Materials and Applications、Ga2O3 and related materials、Nanowire Synthesis and Applications

Utilizing the short lifetime of hot electrons, ultrasensitive hot-electron photodetectors with fast response speed can be developed that have the potential to carve a niche among the photoconductive devices. Herein, high-performance WSe 2 photodetectors are fabricated based on hot-electron transportation, in which an ultrathin Al 2 O 3 layer enables screening of high-energy hot electrons and promises ultrasensitive response to incident light, and the built-in electric field in Schottky junctions separates the photoinduced carriers for fast transient recovery. The hot-electron photodetectors demonstrated a high rectification ratio of 10 7 and an extremely low dark current of 1 pA/μm with a high I light / I dark ratio of 1.8 × 10 6 . Moreover, a high responsivity of 3.69 A/W and detectivity of 2.39 × 10 13 Jones at an incident light power of 5.0 μW/cm 2 are simultaneously achieved. The present strategy offers an alternative route for ultrasensitive photodetectors with fast response.