Fabrication and performance characteristics of a NiC multilayer grating for hard X-rays

We have fabricated and tested a lamella multilayer grating for the hard X-ray range with a grating period of 0.97 μm and a NiC multilayer period of 4.0 nm. To obtain large size gratings the fabrication process included holographic lithography and ion-beam etching. The reflectivity measurements obtained using a triple-axis diffractometer have shown that the diffraction efficiency and the relative intensities of the diffracted orders strongly depend on the incident angle. A very encouraging result is the possibility to direct practically all diffracted energy to any one first order with total suppression of the other orders.