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To develop high quality dispersion optics in the X-ray region, the sliced multilayer transmission grating is examined. Dynamical diffraction theory is used to calculate the diffraction property of this volume grating. A WSi_2/Si multilayer with a d-spacing of 14.3 nm and bi-layer number of 300 is deposited on a superpolished silicon substrate by direct current magnetron sputtering technology. To make the transmission grating, the multilayer is sliced and thinned in the cross-section direction to a depth of 23-25 μm. The diffraction efficiency of the grating is measured at E = 8.05 keV, and the 1st-order efficiency is 19%. The sliced multilayer grating with large aspect ratio and nanometer period can be used for high efficiency and high dispersion optics in the X-ray region.

A linear zone plate named multilayer laue lens (MLL) is fabricated using a depth-graded multilayer structure. The lens shows considerable potential in focusing an X-ray beam into a nanometer scale with high efficiency. In this letter, a depth-graded multilayer consisting of 324 alternating WSi_2 and Si layers with a total thickness of 7.9 µm is deposited based on the thickness sequence according to the demands of the zone plate law. Subsequently, the multilayer sample is sliced and thinned to an ideal depth along the cross-section direction using raw abrasives and diamond lapping. Finally, the cross-section is polished by a chemical mechanical polishing (CMP) technique to remove the damages and improve the surface smoothness. The final depth of the MLL is approximately 7 µm with an achieved aspect ratio greater than 400. Results of scanning electron microscopy (SEM) and atomic force microscopy (AFM) indicate that interfaces are sharp, and the multilayer structure remains undamaged after the thinning and polishing processes. The surface roughness achieved is 0.33 nm.

Aperiodic molybdenum/silicon (Mo/Si) multilayer designed as a broadband reflective mirror with mean reflectivity of 10% over a wide wavelength range of 12.5-28.5 nm at incidence angle of 5? is developed using a numerical optimized method. The multilayer is prepared using direct current magnetron sputtering technology. The reflectivity is measured using synchrotron radiation. The measured mean reflectivity is 7.0% in the design wavelength range of 12.5-28.5 nm. This multilayer broadband reflective mirror can be used in extreme ultraviolet measurements and will greatly simplify the experimental arrangements.