超导纳米线三维结构的均匀性研究

Superconducting nanowire single photon detectors are widely used in quantum key distribution, weak light detection, long distance imaging, deep space communications and so on. Superconducting nanowires with thickness of 3-10 nm and width of 50-200 nm are the key components of SNSPD devices. Material uniformity and homogeneity of graphics of nanowires directly determine important parameters of the device such as detection efficiency, dark count rate. Uniform nanowires are also keys of increasing device yield and device consistency, and basis for the preparation of a larger array device and the expansion of device applications areas. Combining COMSOL simulation and a variety of characterizing tools, this project will work on the basis of the front, deeply explore the relationship between the longitudinal dimension of the film crystalline and defects, surface and interface structure, the transverse dimensions of nanowire size and shape and the device performance, from three aspects which are the electro-thermal model, the growth and characterization of thin film materials. Evaluation system of three-dimensional structures of nanowires will be built with graphical software analysis. Using thin film buffer layer, exposure and graphic compensation, to superconducting nanowire uniformity will be comprehensively improved , thus breaking the two major bottleneck of the device size and yield, and providing support for further optimization and development of the SNSPD device.

超导纳米线单光子探测器(SNSPD)在量子密钥分发、微弱光检测、远距离成像、深空通讯等领域均具有重要应用价值。厚度在3-10纳米、宽度在50-200 纳米的超导线条是SNSPD器件的核心。纳米线条的材料均匀性和图形均匀性直接决定了器件的探测效率、暗记数等重要参数，均匀的纳米线条也是提高器件成品率和一致性的关键，是制备更大规模阵列器件、扩展器件应用领域的基础。本项目将在前面的工作基础之上，从电热模型分析、薄膜材料生长及性能表征三方面着手，通过COMSOL软件仿真结合多种表征手段深入探究纵向维度上薄膜的结晶状态和缺陷、表面和界面结构，横向维度上纳米线条尺寸和形状等与器件性能之间的关系。利用图形分析软件建立纳米线条三维结构均匀性评价体系。采用薄膜缓冲层、曝光补偿、图形补偿等措施全方位提高超导纳米线条均匀性，从而突破器件规模和成品率两大瓶颈，为进一步优化器件性能和推进器件的发展提供支撑。

超导纳米线单光子探测器(SNSPD)在量子密钥分发、微弱光检测、远距离成像、深空通讯等领域均具有重要应用价值。厚度在3-10纳米、宽度在50-200 纳米的超导线条是SNSPD器件的核心。纳米线条的材料均匀性和图形均匀性直接决定了器件的探测效率、暗记数等重要参数，均匀的纳米线条也是提高器件成品率和一致性的关键，是制备更大规模阵列器件、扩展器件应用领域的基础。本项目从薄膜材料生长、纳米线优化加工及薄膜及纳米线均匀性分析三方面着手，结合多种表征手段深入探究纵向维度上薄膜的结晶状态和缺陷、表面和界面结构，横向维度上纳米线条尺寸和形状等与器件性能之间的关系。利用元素成像和图形分析手段建立纳米线条结构均匀性评价体系。采用增加靶材面积、添加缓冲层、保护层、图形优化等措施全方位提高超导纳米线条均匀性，有效提升了器件的关键性能，并将高性能器件应用到了测距和成像等领域。这些都为进一步优化器件性能和推进器件的发展提供支撑。