Lattice Defect Engineering Enables Performance-Enhanced MoS2 Photodetection through a Paraelectric BaTiO3 Dielectric
Lattice Defect Engineering Enables Performance-Enhanced MoS2 Photodetection through a Paraelectric BaTiO3 Dielectric
复制标题
晶格缺陷工程通过顺电 BaTiO3 电介质实现性能增强的 MoS2 光电检测
DOI：
10.1021/acsnano.1c03402
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发表时间：
2021
期刊：
影响因子：
17.1
通讯作者：
Hu Wanbiao
中科院分区：
文献类型：
--
作者：
Zhang Wan;Qiu Feng;Li Yong;Zhang Rui;Liu Huan;Li Lun;Xie Jiyang;Hu Wanbiao
载流子迁移率和密度在纳米光电/电子器件中本质上很重要。高介电常数耦合极化场栅极铁电体经常被研究，并且部分能够实现光响应的大规模调谐，但它们的光吸收和载流子密度似乎通常无效。这就提出了类似的高介电常数顺电栅极电介质是否可以实现调谐以及如何建立所涉及的原理的问题。本研究通过在高介电常数顺电材料中刻意引入晶格缺陷，探索立方BaTiO3（c-BTO）来制造具有超高探测能力和出色场效应特性的MoS2光电探测器。采用基于有机金属的旋涂加退火方法合成c-BTO，通过适当引入晶格缺陷，优化厚度（300 nm），同时保持大的介电常数（1k Hz下为55）和低介电损耗（1k Hz下为0.06），从而增强了可见光区的吸收。由于协同增强的迁移率和光吸收，MoS2/BTO FET 表现出良好的优点，例如，高性能光电探测器的开/关比、亚阈值摆幅和迁移率，具有出色的响应率 (600 AW-1) 和探测率 (1.25 × 1012Jones)。因此，这项工作有助于建立晶格缺陷引起的子带隙吸收地形图，以协同增强高性能光电探测器探索的光响应。
Carrier mobility and density are intrinsically important in nanophoto/electronic devices. High-dielectric-constant coupled polarization-field gate ferroelectrics are frequently studied and partially capable in achieving large-scale tuning of photoresponse, but their light absorption and carrier density seem generally ineffective. This raises questions about whether a similarly high-dielectric-constant paraelectric gate dielectric could enable tuning and how the principles involved could be established. In this study, by deliberately introducing lattice defects in high-dielectric-constant paraelectric, cubic BaTiO3(c-BTO) was explored to fabricate MoS2photodetectors with ultrahigh detection ability and outstanding field-effect traits. An organic-metal-based spin-coating cum annealing method was used for the c-BTO synthesis, with an optimized thickness (300 nm), by introducing lattice defects properly but maintaining a large dielectric constant (55 at 1k Hz) and low dielectric loss (0.06 at 1k Hz), which renders the enhanced visible-light region absorption. As a result of the synergistically enhanced mobility and photoabsorption, the MoS2/BTO FET exhibits promising merits, for example, on/off ratio, subthreshold swing, and mobilities for high-performance photodetectors with excellent responsivity (600 AW–1) and detectivity (1.25 × 1012Jones). Thus, this work facilitates the establishment of a lattice defect induced sub-bandgap absorption landmap for synergistically enhanced photoresponse for high-performance photodetector exploration.