An optimized design of the XIL beam splitter grating combining advanced silicon etching with silicon oxidation technology

作者：Zhu Weizhong^*; Wu Yanqing; Shi Peixiong; Guo Zhi; Tai Renzhong; Xu Hongjie

来源：Nuclear Techniques, 2008, 31(6): 415-419.

In this paper, diffraction efficiency of SiO2 gratings was calculated based on the rigorous coupled-wave analysis, with normal incidence of a 13.4 nm (92.5 eV) EUV light on a grating of 140 nm period. It was found that the maximal first order diffraction efficiency of the SiO2 grating was much higher than the Si grating, and higher than the Cr/Si3N4 compound gratings currently used at PSI. A new method, which combines advanced silicon etching with silicon oxidation technology, was employed to make the SiO2 nano-grating with high aspect ratio. This method, for making the beam splitter grating especially, solves the problem of direct SiO2 etching and will be used for the soft X-ray interference lithography endstation at SSRF.

• 出版日期2008