Self-assembly In2Se3/SnSe2 heterostructure array with suppressed dark current and enhanced photosensitivity for weak signal
Self-assembly In2Se3/SnSe2 heterostructure array with suppressed dark current and enhanced photosensitivity for weak signal
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自组装In2Se3/SnSe2异质结构阵列具有抑制暗电流和增强弱信号光敏性
DOI：
10.1007/s40843-020-1354-2
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发表时间：
2020
影响因子：
8.1
通讯作者：
Li Jingbo
中科院分区：
文献类型：
--
作者：
Zheng Zhaoqiang;Chen Peifeng;Lu Jianting;Yao Ji;ong;Zhao Yu;Zhang Menglong;Hao Mingming;Li Jingbo
基于层状材料的功能范德华(VdWs)异质结在下一代光电子器件中显示出巨大的潜力。到目前为止，基于堆积或外延生长技术已经研究了大量的VdW异质结构。然而，复杂的合成工艺极大地限制了异质结器件阵列的大规模集成，这对实际应用是必不可少的。本文利用脉冲激光沉积(PLD)技术自组装了一种面外垂直In2Se3/SnSe2异质结作为光敏通道的平面型光电探测器阵列。利用垂直内置场来抑制暗电流和分离光生载流子。所实现的器件具有6.3 pA的超低暗电流、8.8×1011琼斯的高探测率和3×104以上的高信噪比。这些性能指标不仅比纯In2Se3器件高一个数量级，而且显示了检测微弱信号的独特优势。此外，这种异质结构光电探测器阵列还可以构建在柔性聚酰亚胺(PI)衬底上。这些柔性器件还显示出有效的光检测能力，即使在200次弯曲循环后，光响应也保持不变。这些发现为下一代大面积高集成度光电子技术的发展铺平了道路。
Functional van der Waals (vdWs) heterostructures based on layered materials have shown tremendous potential in next-generation optoelectronic devices. To date, numerous vdWs heterostructures have been investigated based on stacking or epitaxial growth technology. However, the complicated synthesis process greatly limits the large-scale integration of the heterostructure device array, which is essential for practical applications. Here, a planar photodetector array with an out-of-plane vertical In2Se3/SnSe2 heterostructure as the photosensitive channel was self-assembled through a pulsed laser deposition (PLD) technique. The vertical built-in field was exploited to suppress the dark current and separate the photogenerated carriers. The realized devices possess an ultralow dark current of 6.3 pA, combined with a high detectivity of 8.8×1011 Jones and a high signal-to-noise ratio (SNR) beyond 3×104. These performance metrics not only are one order of magnitude superior to pure In2Se3 device, but also demonstrate the unique advantage of detecting weak signals. In addition, this heterostructure photodetector array can further be constructed on flexible polyimide (PI) substrate. These flexible devices also demonstrate effective light detection capability and the photoresponse remains unchanged even after 200 cycles of bending. These findings pave a way toward the development of next-generation large area and high integration optoelectronic technologies.