Li Hailan, Chen Yuexing, Li Chuanhao, Li Kanghua, Su Zhenghua, Luo Jingting, Zheng Zhuanghao, Liang Guangxing, Chen Shuo
Institute of Thin Film Physics and Applications, Shenzhen Key Laboratory of Advanced Thin Films and Applications, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, State Key Laboratory of Radio Frequency Heterogeneous Integration, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
Wuhan National Laboratory for Optoelectronics (WNLO) and School of Optical and Electronic Information (SOEI), Huazhong University of Science and Technology, Wuhan, 430074, China.
Small. 2025 Sep 10:e06749. doi: 10.1002/smll.202506749.
Antimony selenide (SbSe), a narrow-bandgap semiconductor with strong light absorption, exhibits photoresponse up to ≈1050 nm due to its intrinsic 1.15 eV bandgap. To extend detection into the near-infrared (NIR, 700-1350 nm), Bi-alloyed (BiSb)Se is developed via vacuum sputtering and postselenization. Bi incorporation redshifts the absorption edge to 1350 nm, thereby broadening the photodetection window. At its peak external quantum efficiency of 905 nm, the (BiSb)Se device achieves a responsivity of 1.01 A W and detectivity of 9.77 × 10 Jones, surpassing the undoped counterpart, which shows 0.17 A W and 8.87 × 10 Jones. Importantly, at 1310 nm, the (BiSb)Se device maintains a detectable photocurrent with a responsivity of 0.27 µA W and detectivity of 4.63 × 10 Jones, confirming the extended spectral response. Under 1064 nm pulsed excitation, it exhibits rise and decay times of 10 and 63 ns, respectively-nearly tenfold faster than the undoped version. These improvements result from Bi-induced bandgap modulation, which optimizes band alignment, suppresses interfacial trap states, and promotes anisotropic carrier transport along the quasi-one-dimensional ribbon structure. This work demonstrates a scalable and low-toxicity approach for achieving extended and fast NIR detection, well-suited for future multispectral imaging and biomedical sensing.
硒化锑（SbSe）是一种具有强光吸收能力的窄带隙半导体，由于其固有1.15电子伏特的带隙，其光响应可达约1050纳米。为了将检测范围扩展到近红外（NIR，700 - 1350纳米），通过真空溅射和后硒化工艺制备了铋合金化的（BiSb）Se。铋的掺入使吸收边缘红移至1350纳米，从而拓宽了光电探测窗口。在其905纳米的峰值外量子效率下，（BiSb）Se器件实现了1.01安/瓦的响应度和9.77×10琼斯的探测率，超过了未掺杂的同类器件，后者的响应度为0.17安/瓦，探测率为8.87×10琼斯。重要的是，在1310纳米处，（BiSb）Se器件保持可检测的光电流，响应度为0.27微安/瓦，探测率为4.63×10琼斯，证实了其扩展的光谱响应。在1064纳米脉冲激发下，它的上升和衰减时间分别为10纳秒和63纳秒，比未掺杂版本快近十倍。这些改进源于铋诱导的带隙调制，该调制优化了能带排列，抑制了界面陷阱态，并促进了沿准一维带状结构的各向异性载流子传输。这项工作展示了一种可扩展且低毒性的方法来实现扩展和快速的近红外检测，非常适合未来的多光谱成像和生物医学传感。
