MoS2-HgTe Quantum Dot Hybrid Photodetectors beyond 2 μm
MoS2-HgTe Quantum Dot Hybrid Photodetectors beyond 2 μm
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DOI：
10.1002/adma.201606576
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发表时间：
2017-05-03
影响因子：
29.4
通讯作者：
Konstantatos, Gerasimos
中科院分区：
文献类型：
--
作者：
Huo, Nengjie;Gupta, Shuchi;Konstantatos, Gerasimos
碲化汞（HgTe）胶体量子点（CQDs）由于其低成本、溶液可加工、在短波和中红外光谱范围内具有尺寸可调的吸收特性，已成为中短波红外光电探测的理想材料。然而，低迁移率和光增益差限制了碲化汞CQD为基础的光电探测器的响应度只有几十mA W-1。这里，HgTe CQD集成在TiO 2封装的MoS 2晶体管沟道上，以形成具有约10（6）A W-1的高响应度的混合光电晶体管，这是迄今为止报道的HgTe QD的最高响应度。通过在由MoS 2的栅极调制电流使能的耗尽区中操作光电晶体管，噪声电流被显著抑制，导致在2 μ m的波长下实验测量的约为10（12）琼斯的比探测率D*。这项工作首次展示了混合2D/QD探测器技术的潜力，以引人注目的灵敏度达到2 μ m以上的波长。
Mercury telluride (HgTe) colloidal quantum dots (CQDs) have been developed as promising materials for the short and mid-wave infrared photodetection applications because of their low cost, solution processing, and size tunable absorption in the short wave and mid-infrared spectrum. However, the low mobility and poor photogain have limited the responsivity of HgTe CQD-based photodetectors to only tens of mA W-1. Here, HgTe CQDs are integrated on a TiO2 encapsulated MoS2 transistor channel to form hybrid phototransistors with high responsivity of approximate to 10(6) A W-1, the highest reported to date for HgTe QDs. By operating the phototransistor in the depletion regime enabled by the gate modulated current of MoS2, the noise current is significantly suppressed, leading to an experimentally measured specific detectivity D* of approximate to 10(12) Jones at a wavelength of 2 mu m. This work demonstrates for the first time the potential of the hybrid 2D/QD detector technology in reaching out to wavelengths beyond 2 mu m with compelling sensitivity.