Photodetectors (PDs) based on mix‐dimensional heterojunctions (MDHJs) built from 2D layered materials and covalent‐bonded semiconductors show the prospect of compensating the intrinsic weakness of 2D materials to realize their full potential. However, there is an open issue to improve the temporal response of PDs while maintaining high gain and sensitivity. Herein, photoconductive type MDHJs PDs with 2D InSe and covalent‐bonded CdTe thin film are designed and fabricated in which InSe is the active layer and CdTe is the medium gain one. The conductivity of InSe is improved by exceeding 50 times led by the formation of p–p heterojunction because of that an interfacial hole accumulation at InSe side and a built‐in field at CdTe one are formed. Benefiting from the synergistic function of photoconductive and photogating effects, carrier recirculation induced responsitivity, detectivity, and external quantum efficiency with orders of magnitude increment reach 4.31 × 104 AW−1, 7.55 × 1013 Jones and 1.01 × 107%, and more optimal response time than those of other InSe PDs is demonstrated. This device construction strategy with exceptional performance hints at the prospect of optoelectronic devices of 2D InSe.

中文翻译：

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具有界面空穴层的 InSe/CdTe 异质结构载流子再循环诱导的超灵光电探测器


基于 2D 分层材料和共价键合半导体构建的混合维异质结 （MDHJ） 的光电探测器 （PD） 显示出补偿 2D 材料固有弱点以充分发挥其潜力的前景。然而，在保持高增益和灵敏度的同时改善 PD 的时间响应是一个悬而未决的问题。在此，设计并制备了具有 2D InSe 和共价键合 CdTe 薄膜的光电导型 MDHJs PDs，其中 InSe 是活性层，CdTe 是中等增益层。InSe 的电导率提高了 50 倍以上，这是由 p-p 异质结的形成导致的，因此在 InSe 侧形成了界面空穴积累，在 CdTe 侧形成了内置场。得益于光导和光门效应的协同作用，载流子再循环诱导的响应度、探测性和外部量子效率以数量级增量达到 4.31 × 10 ⁴ AW ⁻¹ 、7.55 × 10 ¹³ Jones 和 1.01 × 10 ⁷ %，并且证明了比其他 InSe PD 更优化的响应时间。这种具有卓越性能的器件构建策略暗示了 2D InSe 光电器件的前景。