论文标题
基于图像 - 历史图的二级电子计数以评估SEM中的侦探量子效率
Image-Histogram-based Secondary Electron Counting to Evaluate Detective Quantum Efficiency in SEM
论文作者
论文摘要
扫描电子显微镜是有机和无机材料的纳米级成像的强大工具。表征这些显微镜性能限制的重要指标是侦探量子效率（DQE），它测量了SE检测器检测到的发射二级电子（SES）的分数。但是，测量DQE的通用技术近似于泊松分布的SE发射过程，这可能导致不正确的DQE值。在本文中，我们引入了一种用于测量DQE的技术，其中我们直接使用图像直方图从样品中检测到的二次电子的平均数量。该技术不假定SES的泊松分布，并且可以在更广泛的成像条件下准确测量DQE。作为我们技术的演示，我们将DQE的变化映射为显微镜中工作距离的函数。
Scanning electron microscopy is a powerful tool for nanoscale imaging of organic and inorganic materials. An important metric for characterizing the limits of performance of these microscopes is the Detective Quantum Efficiency (DQE), which measures the fraction of emitted secondary electrons (SEs) that are detected by the SE detector. However, common techniques for measuring DQE approximate the SE emission process to be Poisson distributed, which can lead to incorrect DQE values. In this paper, we introduce a technique for measuring DQE in which we directly count the mean number of secondary electrons detected from a sample using image histograms. This technique does not assume Poisson distribution of SEs and makes it possible to accurately measure DQE for a wider range of imaging conditions. As a demonstration of our technique, we map the variation of DQE as a function of working distance in the microscope.
