The main advantage of Bragg reflection from a multilayer mirror as a monochromator for hard X-rays, is the higher photon flux density because of the larger spectral bandpass compared with crystal lattice reflection. The main disadvantage lies in the strong modulations of the reflected beam profile. This is a major issue for micro-imaging applications, where multilayer-based monochromators are frequently employed to deliver high photon flux density. A subject of particular interest is the origin of the beam profile modifications, namely the irregular stripe patterns, induced by the reflection on a multilayer. For multilayer coatings in general it is known that the substrate and its surface quality significantly influence the performance of mirrors, as the coating reproduces to a certain degree the roughness and shape of the substrate. This proceedings article reviews recent experiments that indicate potential options for producing wave front-preserving multilayer mirrors, as well as new details on the particular mirrors our group has extensively studied in the past.

Date Published: 17 September 2014
PDF: 7 pages
Proc. SPIE 9207, Advances in X-Ray/EUV Optics and Components IX, 92070V (17 September 2014); doi: 10.1117/12.2060801

Published in SPIE Proceedings Vol. 9207:
Advances in X-Ray/EUV Optics and Components IX
Christian Morawe; Ali M. Khounsary; Shunji Goto, Editor(s)