Optimization of high-performance multilayer monochromator at the Diamond Light Source

Multilayer monochromators offer substantial advantages over traditional crystal-based monochromators. By integrating a multilayer structure, these monochromators can efficiently deliver a high photon flux density and speed up the data acquisition processes, thereby significantly enhancing synchrotron-based experiments. This study focuses on advancing the development of multilayer optics used for the monochromator upgrade of the KMX I24 beamline at the Diamond Light Source. The multilayer monochromator is designed to operate optimally at energies of 12.4 keV and 22.4 keV to maximize the flux. Two multilayer systems including NiV/B4C and Ru/B4C are fabricated using the newly developed Multilayer Deposition System at the Diamond Light Source under the optimized condition. Results indicate that replacing Ni with NiV improves the sputtering stability and interface roughness, while reactive sputtering of Ru/B4C enhances the interface quality of the multilayer. A reflectivity of 92.8% and 89.2% is achieved at 8.048 keV for a 150-bilayer of NiV/B4C and a 70-bilayer of Ru/B4C, respectively.