Development of High‐Performance Multilayer Monochromators

Abstract Multilayer monochromators are crucial optical elements for monochromatizing intense X‐ray beams in applications demanding high photon flux with moderate energy resolution. Achieving high‐performance multilayer monochromators requires optimizing multilayer parameters, using high‐quality substrates, and precisely controlling the deposition process to ensure high reflectivity and eliminate stripe artifacts. This paper presents the design and development, and characterization of double multilayer monochromators (DMM). These coatings are deposited using an optimized mask design to ensure <0.3% sagittal thickness uniformity and employing reactive sputtering in nitrogen gas (N ₂ ) ‐ to enhance multilayer reflectivity. A high reflectivity of 88.7% at 14.0 keV and 85.6% at 22.4 keV is achieved. Furthermore, stripe‐free imaging is achieved in double‐reflection geometry via the use of high‐quality substrates produced using the in‐house ion beam figuring machine. These findings offer valuable insights for developing high‐performance DMMs, paving the way for the next generation of synchrotron optics and instruments.