Calculated performance of multilayer Laue lens based on actual layer thickness and coupled wave theory

• Published in: Optical engineering 2021-09, Vol.60 (9), p.094111-094111
• Main Authors: Yue, Shuaipeng, Zhou, Liang, Li, Ming, Liu, Peng, Ji, Bin, Zhu, Jingtao, Chang, Guangcai
• Format: Article
• Language: English
• ISSN: 0091-3286; 1560-2303
• DOI: 10.1117/1.OE.60.9.094111

The multilayer Laue lens (MLL) is a promising optical element with large numerical aperture and aspect ratio in synchrotron radiation facility to focus hard x-ray to 1 nm with ideal structure. We use a new method of combining actual film thickness and the coupled wave theory to calculate focusing performance. Here, a 17.2-μm-MLL with a focal spot size of 17 nm at 10 keV is designed and fabricated by dynamical diffraction theory and direct current magnetron sputtering technology. Based on a new rate calibration and symbol layer insertion method, we calculate d-spacing of multilayer instead of individual layer thickness and change the order of two layers as a symbol so as not to damage zone plate law. The scanning electron microscope image is smoothed and binary transformed to measure the actual thickness of each layer. The full-width at half-maximum of focus spot is 18 nm, which is close to the theoretical result of 17 nm.