Theories and technologies of extreme ultraviolet

soft X-ray and X-ray regions have made great progress since 1970s

and multilayer mirrors have found wide applications in astronomy

microscopy

material science

synchrotron radiation applications

and plasma diagnostics for their high-reflectivity and good stability

however

they have a poor spectral resolution for X-ray fluorescent measurement and synchrotron radiation monochromator. The spectral resolution of the multilayer must be improved for some high spectral resolution measurements. The spectral resolution can be improved by etching the multilayer into a multilayer grating at different etching ratios by the average density calculation method. W/C multilayers were fabricated by magnetron sputtering and the multilayer gratings were made by normal optical lithography. The results measured by grazing-angle X-ray diffraction show that the multilayer structure in an etched multilayer grating has not been destroyed and the spectral resolution has been improved

which demonstrates that methods proposed for making etched multilayer gratings are suitable for further research.