A WSi<sub>2</sub>/Si multilayer, with 300 bi-layers and a 2.18-nm d-spacing, is designed for X-ray monochromator application. The multilayer is deposited using direct current magnetron sputtering technology. The reflectivity of the 1st-order Bragg peak measured at <i>E</i>=8.05 keV is 38%, and the angular resolution (Δ<i>θ/θ</i>) is less than 1.0%. Fitting results of the reflectivity curve indicate a layer thickness drift of 1.6%, mainly accounting for the broadening of the Bragg peaks. The layer morphology is further characterized by transmission electron microscopy, and a well-ordered multilayer structure with sharp interfaces is observed from the substrate to the surface. The material combination of WSi<sub>2</sub>/Si is a promising candidate for the fabrication of a high-resolution multilayer monochromator in the hard X-ray region.
© 2012 Chinese Optics Letters
Qiushi Huang, Haochuan Li, Jingtao Zhu, Zhanshan Wang, and Yongjian Tang, "Small d-spacing WSi2/Si multilayers for X-ray monochromators," Chin. Opt. Lett. 10, 123401-123401 (2012)