Fabrication and characterization of a Mo/Si multilayer monochromator with a narrow spectral bandwidth in the xuv domain

A new kind of xuv multilayer monochromator with a narrow spectral bandwidth is introduced. This monochromator is based on a Mo/Si multilayer mirror etched according to the profile of a lamellar grating. The fabrication of such a device involving multilayer deposition, UV lithography and reactive ion etching is presented. The monochromator has been characterized by means of the synchrotron radiation around the Si-L edge (100 eV). A reduction of the bandwidth has been observed with respect to the unpatterned mirror by a factor close to 3.