The emergent two-dimensional (2D) material, tin diselenide (SnSe₂), has garnered significant consideration for its potential in image capturing systems, optical communication, and optoelectronic memory. Nevertheless, SnSe₂-based photodetection faces obstacles, including slow response speed and low normalized detectivity. In this work, photodetectors based on SnS/SnSe₂ and SnSe/SnSe₂ p?n heterostructures have been implemented through a polydimethylsiloxane (PDMS)?assisted transfer method. These photodetectors demonstrate broad-spectrum photoresponse within the 405 to 850 nm wavelength range. The photodetector based on the SnS/SnSe₂ heterostructure exhibits a significant responsivity of 4.99 × 10³ A?W^?1, normalized detectivity of 5.80 × 10¹² cm?Hz^1/2?W^?1, and fast response time of 3.13 ms, respectively, owing to the built-in electric field. Meanwhile, the highest values of responsivity, normalized detectivity, and response time for the photodetector based on the SnSe/SnSe₂ heterostructure are 5.91 × 10³ A?W^?1, 7.03 × 10¹² cm?Hz^1/2?W^?1, and 4.74 ms, respectively. And their photodetection performances transcend those of photodetectors based on individual SnSe₂, SnS, SnSe, and other commonly used 2D materials. Our work has demonstrated an effective strategy to improve the performance of SnSe₂-based photodetectors and paves the way for their future commercialization.

采用金属有机化学气相沉积（MOCVD）工艺在p-GaAs（100）衬底上外延了Ga₂O₃薄膜并制备了n-Ga₂O₃/p-GaAs异质结日盲紫外探测器。通过X射线衍射仪、原子力显微镜、场发射扫描电子显微镜等方法对Ga₂O₃薄膜表面形貌、晶体质量进行了测试与分析。结果表明，Ga₂O₃薄膜呈单一晶向，薄膜表面平整且为Volmer-Weber模式外延。测试表明，n-Ga₂O₃/p-GaAs异质结探测器具有明显的整流特性。器件在5 V反向偏压和紫外光（254 nm）照射下实现了超过3.0×10⁴的光暗电流比、7.0 A/W的响应度、3412%的外量子效率、4.6×10¹³ Jones的探测率。我们利用TCAD软件对器件结构进行仿真，得到了器件内的电场分布和能带结构，并分析了器件的工作原理。该异质结探测器性能较好，制造工艺简单，为Ga₂O₃超灵敏日盲紫外探测器的研制提供了新途径。

近年来，杂化钙钛矿半导体材料由于其带隙可调、吸收系数高、载流子迁移率高、成本低廉等诸多优点，在光电器件领域备受青睐，如太阳能电池、电致发光器件、光电探测器等。其中，钙钛矿单晶薄膜因其无晶界、杂质和缺陷含量低等特点，展现出更为优异的光学、电学特性，成为制备高性能光电器件的理想材料体系。然而，钙钛矿单晶薄膜常采用空间限域法直接生长在空穴传输层上，不可避免地将导致界面缺陷和载流子层间输运等问题，严重制约了钙钛矿单晶薄膜光电探测器的性能。为此，本文通过引入模板剥离法工艺技术，在钙钛矿单晶薄膜两侧分别蒸镀功能层材料，制备了结构为Cu/BCP/C₆₀/MAPbBr₃/MoO₃/Ag的钙钛矿单晶薄膜光电探测器。基于模板剥离法，两侧蒸镀的功能层与钙钛矿单晶薄膜接触紧密，将有效改善载流子的注入和传输；同时，优化的器件结构以及考虑能带匹配等因素可实现高灵敏、响应快速的钙钛矿单晶薄膜光电探测器。改进后器件的开关比高达3.1 × 10³，响应度可达7.15 A/W，探测率为5.39 × 10¹² Jones，外量子效率达到1794%。该工作为进一步改善和提升钙钛矿单晶薄膜光电探测器的探测性能提供了一种可行性技术方案。

近红外光（NIR）探测技术在**、通信和工业应用中发挥着重要的作用，巨大的市场需求带动了NIR光电探测器（PDs）研究的快速发展。具有双光子或多光子泵浦特性的稀土掺杂上转换纳米颗粒（UCNPs）可以将NIR光子转换为可见光子或紫外光子，并被禁带宽度更宽的半导体吸收，进而制备出性能优异的上转换PDs。然而，NIR窄带上转换PDs的实现仍然面临一些困难，例如稀土离子荧光量子效率低、需要高泵浦阈值才能实现可探测的上转换发光。在此，我们利用NaYF₄∶4%Er UCNPs与钙钛矿半导体层相结合，实现了1 550 nm的窄带上转换PDs。通过使用具有局域表面等离子体共振效应的银纳米棒层（Ag NRs）增强了UCNPs的上转换发光，从而降低了上转换PDs的泵浦阈值。基于Ag NRs/NaYF₄∶4%Er UCNPs/MAPbI₃ 复合结构的PDs的最佳响应度（R）和探测率（D^*）分别约为48.5 mA/W和5.7×10⁸ Jones。与纯UNCP/MAPbI₃ PDs相比，R和D^*均提高了一个数量级。我们成功地构建了一种简单的策略来制造出稳定的近红外窄带PDs。

For the measurement of responsivity of an infrared photodetector, the most-used radiation source is a blackbody. In such a measurement system, distance between the blackbody, the photodetector and the aperture diameter are two parameters that contribute most measurement errors. In this work, we describe the configuration of our responsivity measurement system in great detail and present a method to calibrate the distance and aperture diameter. The core of this calibration method is to transfer direct measurements of these two parameters into an extraction procedure by fitting the experiment data to the calculated results. The calibration method is proved experimentally with a commercially extended InGaAs detector at a wide range of blackbody temperature, aperture diameter and distance. Then proof procedures are further extended into a detector fabricated in our laboratory and consistent results were obtained.