Abstract. Background: The secondary electron yield (SEY) of materials is important for topics as nanoparticle photoresists and extreme ultraviolet (EUV) optics contamination. Aim: Experimentally measure SEY and secondary electron energy distributions for Ru, Sn, and Hf oxide. Approach: The SEY and energy distribution resulting from 65 to 112 eV EUV radiation are measured for thin-film oxides or films with native oxide. Results: The total SEY can be explained by EUV absorption in the topmost nanometer of (native) oxide of the investigated materials. Conclusions: Although the relative SEY of Ru and Sn is well-explained by the difference in EUV absorption properties, the SEY of HfO2 is almost a factor 2 higher than expected. Based on the energy distribution of secondary electrons, this may be related to a lower barrier for secondary electron emission.

中文翻译：

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Ru、Sn 和 Hf 氧化物薄膜的极紫外二次电子产率测量

摘要。背景：材料的二次电子产率 (SEY) 对于纳米粒子光刻胶和极紫外 (EUV) 光学污染等主题很重要。目的：通过实验测量 Ru、Sn 和 Hf 氧化物的 SEY 和二次电子能量分布。方法：测量薄膜氧化物或具有天然氧化物的薄膜的 SEY 和 65 至 112 eV EUV 辐射产生的能量分布。结果：总 SEY 可以通过研究材料的（天然）氧化物的最顶层纳米的 EUV 吸收来解释。结论：虽然 Ru 和 Sn 的相对 SEY 可以通过 EUV 吸收特性的差异得到很好的解释，但 HfO2 的 SEY 几乎比预期的高 2 倍。基于二次电子的能量分布，这可能与二次电子发射的较低势垒有关。