Modern science is dependent on imaging on the nanoscale, often achieved through processes that detect secondary electrons created by a highly focused incident charged particle beam. Multiple types of measurement noise limit the ultimate trade-off between the image quality and the incident particle dose, which can preclude useful imaging of dose-sensitive samples. Existing methods to improve image quality do not fundamentally mitigate the noise sources. Furthermore, barriers to assigning a physically meaningful scale make the images qualitative. Here, we introduce ion count-aided microscopy (ICAM), which is a quantitative imaging technique that uses statistically principled estimation of the secondary electron yield. With a readily implemented change in data collection, ICAM substantially reduces source shot noise. In helium ion microscopy, we demonstrate 3 × dose reduction and a good match between these empirical results and theoretical performance predictions. ICAM facilitates imaging of fragile samples and may make imaging with heavier particles more attractive.

中文翻译：

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使用离子计数辅助显微镜进行散粒噪声抑制的二次电子成像


现代科学依赖于纳米级成像，通常通过检测高度聚焦的入射带电粒子束产生的二次电子的过程来实现。多种类型的测量噪声限制了图像质量和入射粒子剂量之间的最终权衡，这可能妨碍对剂量敏感样品的有用成像。现有的提高图像质量的方法并不能从根本上减轻噪声源。此外，分配具有物理意义的尺度的障碍使图像定性。在这里，我们介绍离子计数辅助显微镜（ICAM），这是一种定量成像技术，利用统计原理估计二次电子产率。通过轻松实施数据收集方面的更改，ICAM 显着降低了源散粒噪声。在氦离子显微镜中，我们证明了 3 ×剂量减少以及这些经验结果与理论性能预测之间的良好匹配。 ICAM 有助于对易碎样品进行成像，并且可能使较重颗粒的成像更具吸引力。