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Title: Reflection Passband Broadening by Aperiodic Designs of EUV/Soft X-ray Multilayers

Abstract

By using three conventional optimization algorithms, we have developed computer programs of layer thickness designing for reflection passband broadening of EUV/soft X-ray multilayers. Three programs with optimization by Simplex, quasi-Newton and Gradient methods were found to be effective to search for aperiodic Mo/Si multilayers of a leveled reflectance of 35% within a wavelength region between 13 nm and 15 nm, though the thickness structures were considerably different. For much shorter wavelengths in the water window, solutions of Cr/Sc multilayers were also found for a leveled 30% reflectance between 3.14 nm and 3.16 nm, and also for a 15% reflectance between 3.13 nm and 3.17 nm. The bandwidth {lambda}/{delta}{lambda} of these designs were improved from 286 of periodic multilayer to 137 and 66, respectively. Two practical design solutions were used to fabricate aperiodic Mo/Si multilayer mirrors by our ion beam sputtering system. The samples show EUV reflectance of more than 15% between 13 nm and 15 nm.

Authors:
 [1]
  1. Research Center for Soft X-ray Microscopy, IMRAM, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan)
Publication Date:
OSTI Identifier:
21049312
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 879; Journal Issue: 1; Conference: 9. international conference on synchrotron radiation instrumentation, Daegu (Korea, Republic of), 28 May - 2 Jun 2006; Other Information: DOI: 10.1063/1.2436355; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALGORITHMS; CHROMIUM; DESIGN; EXTREME ULTRAVIOLET RADIATION; INTERFACES; ION BEAMS; LAYERS; MIRRORS; MOLYBDENUM; OPTICS; OPTIMIZATION; PERIODICITY; REFLECTION; SILICON; SOFT X RADIATION; SPUTTERING; WATER; WAVELENGTHS

Citation Formats

Tsuru, Toshihide. Reflection Passband Broadening by Aperiodic Designs of EUV/Soft X-ray Multilayers. United States: N. p., 2007. Web. doi:10.1063/1.2436355.
Tsuru, Toshihide. Reflection Passband Broadening by Aperiodic Designs of EUV/Soft X-ray Multilayers. United States. doi:10.1063/1.2436355.
Tsuru, Toshihide. Fri . "Reflection Passband Broadening by Aperiodic Designs of EUV/Soft X-ray Multilayers". United States. doi:10.1063/1.2436355.
@article{osti_21049312,
title = {Reflection Passband Broadening by Aperiodic Designs of EUV/Soft X-ray Multilayers},
author = {Tsuru, Toshihide},
abstractNote = {By using three conventional optimization algorithms, we have developed computer programs of layer thickness designing for reflection passband broadening of EUV/soft X-ray multilayers. Three programs with optimization by Simplex, quasi-Newton and Gradient methods were found to be effective to search for aperiodic Mo/Si multilayers of a leveled reflectance of 35% within a wavelength region between 13 nm and 15 nm, though the thickness structures were considerably different. For much shorter wavelengths in the water window, solutions of Cr/Sc multilayers were also found for a leveled 30% reflectance between 3.14 nm and 3.16 nm, and also for a 15% reflectance between 3.13 nm and 3.17 nm. The bandwidth {lambda}/{delta}{lambda} of these designs were improved from 286 of periodic multilayer to 137 and 66, respectively. Two practical design solutions were used to fabricate aperiodic Mo/Si multilayer mirrors by our ion beam sputtering system. The samples show EUV reflectance of more than 15% between 13 nm and 15 nm.},
doi = {10.1063/1.2436355},
journal = {AIP Conference Proceedings},
number = 1,
volume = 879,
place = {United States},
year = {Fri Jan 19 00:00:00 EST 2007},
month = {Fri Jan 19 00:00:00 EST 2007}
}
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  • No abstract prepared.