Silicon-based photodetectors as the main force in visible and near-infrared detection devices have been deeply embedded in modern technology and human society, but due to the characteristics of silicon itself, its response wavelength is generally less than 1100 nm. It is an interesting study to combine the state-of-art silicon processing with emerging infrared-sensitive Lead sulfide colloidal quantum dots (PbS-CQDs) to produce a photodetector that can detect infrared light. Here, we demonstrated a silicon-compatible photodetector that could be integrated on-chip, and also sensitive to infrared light which is owing to a PbS-CQDs absorption layer with tunable bandgap. The device exhibit extremely high gain which reaches maximum detectivity [Formula: see text], fast response 211/558 μs, and extremely high external quantum efficiency [Formula: see text], which is owing to new architecture and reasonable ligand exchange options. The performance of the device originates from the new architecture, that is, using the photovoltaic voltage generated by the surface of PbS-CQDs to change the width of the depletion layer to achieve detection. Besides, the performance improvement of devices comes from the addition of PbS-CQDs (Ethanedithiol treated) layer, which effectively reduces the fall time and makes the device expected to work at higher frequencies. Our work paves the way for the realization of cost-efficient high-performance silicon compatible infrared optoelectronic devices.

中文翻译：

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具有高灵敏度和快速响应的硅基 PbS-CQDs 红外光电探测器

硅基光电探测器作为可见光和近红外探测装置的主力军，已经深入现代科技和人类社会，但由于硅本身的特性，其响应波长一般小于1100nm。将最先进的硅加工与新兴的红外敏感硫化铅胶体量子点 (PbS-CQD) 相结合，生产出可以检测红外光的光电探测器是一项有趣的研究。在这里，我们展示了一种硅兼容光电探测器，它可以集成在芯片上，并且由于具有可调带隙的 PbS-CQDs 吸收层而对红外光敏感。该器件具有极高的增益，可达到最大探测率[公式：见正文]，快速响应 211/558 μs，以及极高的外部量子效率 [公式：见正文]，这是由于新的架构和合理的配体交换选项。该器件的性能源于新架构，即利用PbS-CQDs表面产生的光伏电压改变耗尽层的宽度来实现检测。此外，器件的性能提升来自于添加 PbS-CQDs（乙二硫醇处理）层，有效地减少了下降时间，使器件有望在更高的频率下工作。我们的工作为实现具有成本效益的高性能硅兼容红外光电器件铺平了道路。利用PbS-CQDs表面产生的光伏电压改变耗尽层的宽度来实现检测。此外，器件的性能提升来自于添加 PbS-CQDs（乙二硫醇处理）层，有效地减少了下降时间，使器件有望在更高的频率下工作。我们的工作为实现具有成本效益的高性能硅兼容红外光电器件铺平了道路。利用PbS-CQDs表面产生的光伏电压改变耗尽层的宽度来实现检测。此外，器件的性能提升来自于添加 PbS-CQDs（乙二硫醇处理）层，有效地减少了下降时间，使器件有望在更高的频率下工作。我们的工作为实现具有成本效益的高性能硅兼容红外光电器件铺平了道路。