For quantitative electron microscopy the comparison of measured and simulated data is essential. Monte Carlo (MC) simulations are well established to calculate the high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) intensities on a non-atomic scale. In this work we focus on the importance of the screening parameter in differential screened Rutherford cross-sections for MC simulations and on the contribution of the screening parameter to the atomic-number dependence of the HAADF-STEM intensity at electron energies ≤ 30 keV. Materials investigated were chosen to cover a wide range of atomic numbers Z to study the Z dependence of the screening parameter. Comparison of measured and simulated HAADF-STEM intensities with different screening parameters known from the literature were tested and failed to generally describe the experimental data. Hence, the screening parameter was adapted to obtain the best match between experimental and MC-simulated HAADF-STEM intensities. The Z dependence of the HAADF-STEM intensity was derived.

中文翻译：

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低电子能量下的微分电子散射截面：屏蔽参数的影响

对于定量电子显微镜，测量数据和模拟数据的比较是必不可少的。蒙特卡罗 (MC) 模拟已经很好地建立了计算非原子尺度上的高角度环形暗场扫描透射电子显微镜 (HAADF-STEM) 强度。在这项工作中，我们关注微分筛选卢瑟福横截面中筛选参数对 MC 模拟的重要性，以及筛选参数对电子能量 ≤ 30 keV 时 HAADF-STEM 强度的原子序数依赖性的贡献。选择所研究的材料以涵盖广泛的原子序数 Z 以研究筛选参数的 Z 依赖性。测试了测量和模拟的 HAADF-STEM 强度与文献中已知的不同筛选参数的比较，但未能普遍描述实验数据。因此，筛选参数被调整以获得实验和 MC 模拟的 HAADF-STEM 强度之间的最佳匹配。导出了 HAADF-STEM 强度的 Z 依赖性。