Nanosphere lithography (NSL) is a bottom‐up, self‐assembly approach that enables rapid, low‐cost patterning of nanoscale features. The practical application and scalability of NSL relies on the ability to achieve defect‐free nanosphere self‐assembly over large substrate areas. Self‐assembly methods for single‐layer nanosphere templates are typically evaluated using scanning electron microscopy (SEM) imaging, with literature reports focusing on maximum area of continuous nanosphere coverage. An alternative performance metric—namely, the percentage of nanospheres exhibiting perfect hexagonal close‐packing (%HCP)—is uniquely critical to NSL precision and repeatability. To enhance current methods of evaluating nanosphere self‐assembly, this work presents an SEM image analysis approach for rapidly quantifying packing defects in single‐layer nanospheres to determine %HCP. The method uses variations in SEM edge effect brightness to distinguish spheres with perfect packing from those in defect configurations or along edges. Comparison of image analysis program results with manual counting of nanospheres indicates that the program has a high degree of accuracy, with a mean error on the %HCP metric of +8.6% (absolute error). The results suggest that the present strategy offers a promising pathway to rapid evaluation of nanosphere self‐assembly for high‐precision NSL applications such as surface‐enhanced Raman scattering, photovoltaic cells, and nanogap electrodes.

中文翻译：

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使用扫描电子显微镜边缘效应对纳米球光刻填充缺陷进行快速定量

纳米球光刻（NSL）是一种自底向上的自组装方法，可对纳米级特征进行快速，低成本的图案化。NSL的实际应用和可扩展性取决于能否在大面积基板上实现无缺陷的纳米球自组装。单层纳米球模板的自组装方法通常使用扫描电子显微镜（SEM）成像进行评估，文献报道的重点是连续纳米球覆盖的最大面积。另一种性能指标，即表现出完美六边形紧密堆积（％HCP）的纳米球的百分比，对NSL的精度和可重复性至关重要。为了增强当前评估纳米球自组装的方法，这项工作提出了一种SEM图像分析方法，用于快速定量单层纳米球中的填充缺陷以确定％HCP。该方法利用SEM边缘效应亮度的变化来区分具有完美堆积的球体与缺陷构造或沿边缘的球体。图像分析程序结果与手动计数纳米球的比较表明，该程序具有很高的准确性，％HCP度量标准的平均误差为+ 8.6％（绝对误差）。结果表明，目前的策略为快速评估纳米NSL的高精度自组装纳米表面的自组装提供了一个有希望的途径，例如表面增强拉曼散射，光伏电池和纳米间隙电极。该方法利用SEM边缘效应亮度的变化来区分具有完美堆积的球体与缺陷构造或沿边缘的球体。图像分析程序结果与手动计数纳米球的比较表明，该程序具有很高的准确性，％HCP度量标准的平均误差为+ 8.6％（绝对误差）。结果表明，目前的策略为快速评估纳米NSL的高精度自组装纳米表面的自组装提供了一个有希望的途径，例如表面增强拉曼散射，光伏电池和纳米间隙电极。该方法利用SEM边缘效应亮度的变化来区分具有完美堆积的球体与缺陷构造或沿边缘的球体。图像分析程序结果与手动计数纳米球的比较表明，该程序具有很高的准确性，％HCP度量标准的平均误差为+ 8.6％（绝对误差）。结果表明，目前的策略为快速评估高精度NSL应用的纳米球自组装（例如表面增强拉曼散射，光伏电池和纳米间隙电极）提供了有希望的途径。