Highly efficient blazed grating with multilayer coating for tender X-ray energies.

Area of Science:

• X-ray optics
• Diffraction gratings
• Multilayer coatings

Background:

• Blazed gratings with multilayer coatings are crucial for suppressing stray and higher-order light in grating monochromators.
• Effective performance is needed for photon energies in the 1-5 keV range.

Purpose of the Study:

• To develop and characterize a blazed grating with a multilayer coating for enhanced performance in X-ray monochromators.
• To optimize the grating for high efficiency and suppression of unwanted light orders.

Main Methods:

• Fabrication of a blazed 2000 lines/mm grating with a 20-period Cr/C multilayer coating.
• Adaptation of multilayer d-spacing (7.3 nm) to line distance (500 nm) and blaze angle (0.84°).
• Measurement of grating efficiency and witness multilayer reflectance.

Main Results:

• Measured efficiency of 35% at 2 keV and a maximum efficiency of 55% at 4 keV.
• Demonstrated strong suppression of higher orders.
• Achieved highest efficiency in the 1.5-3 keV photon energy range.

Conclusions:

• Blazed multilayer gratings are highly effective for stray and higher-order light suppression in the 1-5 keV range.
• These gratings are a favorable dispersing element for low X-ray energy applications.
• The developed grating shows significant potential for X-ray monochromator applications.