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Title: Aperiodic Mo/Si multilayers for hard x-rays

Abstract

In this work we have developed aperiodic Molybdenum/Silicon (Mo/Si) multilayers (MLs) to reflect 16.25 keV photons at a grazing angle of incidence of 0.6° ± 0.05°. To the best of our knowledge this is the first time this material system has been used to fabricate aperiodic MLs for hard x-rays. At these energies new hurdles arise. First of all a large number of bilayers is required to reach saturation. This poses a challenge from the manufacturing point of view, as thickness control of each ML period becomes paramount. The latter is not well defined a priori, due to the thickness of the interfacial silicide layers which has been observed to vary as a function of Mo and Si thickness. Additionally an amorphous-to-crystalline transition for Mo must be avoided in order maintain reasonably low roughness at the interfaces. This transition is well within the range of thicknesses pertinent to this study. Despite these difficulties our data demonstrates that we achieved reasonably flat ML response across the angular acceptance of ± 0.05°, with an experimentally confirmed average reflectivity of 28%. Such a ML prescription is well suited for applications in the field of hard x-ray imaging of highly diverging sources.

Authors:
 [1];  [1];  [2];  [1];  [1];  [1];  [1];  [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  2. Rigaku Innovative Technologies, Inc., Auburn Hills, MI (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1393341
Report Number(s):
LLNL-JRNL-691813
Journal ID: ISSN 1094-4087; OPEXFF
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Optics Express
Additional Journal Information:
Journal Volume: 24; Journal Issue: 16; Journal ID: ISSN 1094-4087
Publisher:
Optical Society of America (OSA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 42 ENGINEERING

Citation Formats

Pardini, Tom, Alameda, Jennifer, Platonov, Yuriy, Robinson, Jeff, Soufli, Regina, Spiller, Eberhard, Walton, Chris, and Hau-Riege, Stefan P. Aperiodic Mo/Si multilayers for hard x-rays. United States: N. p., 2016. Web. doi:10.1364/OE.24.018642.
Pardini, Tom, Alameda, Jennifer, Platonov, Yuriy, Robinson, Jeff, Soufli, Regina, Spiller, Eberhard, Walton, Chris, & Hau-Riege, Stefan P. Aperiodic Mo/Si multilayers for hard x-rays. United States. doi:10.1364/OE.24.018642.
Pardini, Tom, Alameda, Jennifer, Platonov, Yuriy, Robinson, Jeff, Soufli, Regina, Spiller, Eberhard, Walton, Chris, and Hau-Riege, Stefan P. Thu . "Aperiodic Mo/Si multilayers for hard x-rays". United States. doi:10.1364/OE.24.018642. https://www.osti.gov/servlets/purl/1393341.
@article{osti_1393341,
title = {Aperiodic Mo/Si multilayers for hard x-rays},
author = {Pardini, Tom and Alameda, Jennifer and Platonov, Yuriy and Robinson, Jeff and Soufli, Regina and Spiller, Eberhard and Walton, Chris and Hau-Riege, Stefan P.},
abstractNote = {In this work we have developed aperiodic Molybdenum/Silicon (Mo/Si) multilayers (MLs) to reflect 16.25 keV photons at a grazing angle of incidence of 0.6° ± 0.05°. To the best of our knowledge this is the first time this material system has been used to fabricate aperiodic MLs for hard x-rays. At these energies new hurdles arise. First of all a large number of bilayers is required to reach saturation. This poses a challenge from the manufacturing point of view, as thickness control of each ML period becomes paramount. The latter is not well defined a priori, due to the thickness of the interfacial silicide layers which has been observed to vary as a function of Mo and Si thickness. Additionally an amorphous-to-crystalline transition for Mo must be avoided in order maintain reasonably low roughness at the interfaces. This transition is well within the range of thicknesses pertinent to this study. Despite these difficulties our data demonstrates that we achieved reasonably flat ML response across the angular acceptance of ± 0.05°, with an experimentally confirmed average reflectivity of 28%. Such a ML prescription is well suited for applications in the field of hard x-ray imaging of highly diverging sources.},
doi = {10.1364/OE.24.018642},
journal = {Optics Express},
number = 16,
volume = 24,
place = {United States},
year = {Thu Aug 04 00:00:00 EDT 2016},
month = {Thu Aug 04 00:00:00 EDT 2016}
}

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