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Title: X-ray diffraction gratings: Precise control of ultra-low blaze angle via anisotropic wet etching

Abstract

Diffraction gratings are used from micron to nanometer wavelengths as dispersing elements in optical instruments. At shorter wavelengths, crystals can be used as diffracting elements, but due to the 3D nature of the interaction with light are wavelength selective rather than wavelength dispersing. There is an urgent need to extend grating technology into the x-ray domain of wavelengths from 1 to 0.1 nm, but this requires the use of gratings that have a faceted surface in which the facet angles are very small, typically less than 1°. Small facet angles are also required in the extreme ultra-violet and soft x-ray energy ranges in free electron laser applications, in order to reduce power density below a critical damage threshold. In this work, we demonstrate a technique based on anisotropic etching of silicon designed to produce very small angle facets with a high degree of perfection.

Authors:
; ; ; ;  [1];  [2]
  1. Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)
  2. University of California, Berkeley, California 94720 (United States)
Publication Date:
OSTI Identifier:
22594383
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANISOTROPY; CONTROL; CRYSTALS; DAMAGE; DIFFRACTION GRATINGS; ELECTRONS; ENERGY RANGE; ETCHING; FREE ELECTRON LASERS; GRATINGS; POWER DENSITY; SILICON; SOFT X RADIATION; SURFACES; THREE-DIMENSIONAL CALCULATIONS; ULTRAVIOLET RADIATION; WAVELENGTHS; X-RAY DIFFRACTION

Citation Formats

Voronov, Dmitriy L., Naulleau, Patrick, Gullikson, Eric M., Fedorov, Alexei V., Padmore, Howard A., and Lum, Paul. X-ray diffraction gratings: Precise control of ultra-low blaze angle via anisotropic wet etching. United States: N. p., 2016. Web. doi:10.1063/1.4960203.
Voronov, Dmitriy L., Naulleau, Patrick, Gullikson, Eric M., Fedorov, Alexei V., Padmore, Howard A., & Lum, Paul. X-ray diffraction gratings: Precise control of ultra-low blaze angle via anisotropic wet etching. United States. doi:10.1063/1.4960203.
Voronov, Dmitriy L., Naulleau, Patrick, Gullikson, Eric M., Fedorov, Alexei V., Padmore, Howard A., and Lum, Paul. 2016. "X-ray diffraction gratings: Precise control of ultra-low blaze angle via anisotropic wet etching". United States. doi:10.1063/1.4960203.
@article{osti_22594383,
title = {X-ray diffraction gratings: Precise control of ultra-low blaze angle via anisotropic wet etching},
author = {Voronov, Dmitriy L. and Naulleau, Patrick and Gullikson, Eric M. and Fedorov, Alexei V. and Padmore, Howard A. and Lum, Paul},
abstractNote = {Diffraction gratings are used from micron to nanometer wavelengths as dispersing elements in optical instruments. At shorter wavelengths, crystals can be used as diffracting elements, but due to the 3D nature of the interaction with light are wavelength selective rather than wavelength dispersing. There is an urgent need to extend grating technology into the x-ray domain of wavelengths from 1 to 0.1 nm, but this requires the use of gratings that have a faceted surface in which the facet angles are very small, typically less than 1°. Small facet angles are also required in the extreme ultra-violet and soft x-ray energy ranges in free electron laser applications, in order to reduce power density below a critical damage threshold. In this work, we demonstrate a technique based on anisotropic etching of silicon designed to produce very small angle facets with a high degree of perfection.},
doi = {10.1063/1.4960203},
journal = {Applied Physics Letters},
number = 4,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
  • Cited by 1
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