Mo/Be multilayers are promising optical elements for extreme ultraviolet (EUV) lithography and space optics. Experimentally derived optical constants are necessary for accurate and reliable design of beryllium-containing optical coatings. We report optical constants of beryllium derived from synchrotron radiation-based reflectivity data of Mo/Be multilayers. Results are in good agreement with available data in the literature obtained from the well-known absorption measurements of beryllium thin films or foils. We demonstrate synchrotron based at-wavelength reflectometry as an accurate and non-destructive technique for deriving EUV optical constants for materials that are difficult or unstable to make thin foils for absorption measurements.

中文翻译：

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由Mo / Be多层在90至134 eV光谱范围内测定的铍薄层的光学常数

Mo / Be多层膜是用于极紫外（EUV）光刻和太空光学的有前途的光学元件。实验得出的光学常数对于含铍光学涂层的准确可靠设计是必需的。我们报告了铍的光学常数，该常数来自基于Mo / Be多层膜的基于同步辐射的反射率数据。结果与从铍薄膜或箔的众所周知的吸收测量获得的文献中可获得的数据高度吻合。我们证明了基于同步加速器的波长反射法是一种精确且无损的技术，可用于为难以或不稳定地制成用于吸收测量的薄箔的材料推导EUV光学常数。