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Title: Novel Preparation Methods for the Fabrication of Thin-Film EXAFS Samples

Abstract

Thin-film EXAFS samples have been fabricated using semiconductor-processing and wet-chemical etching techniques to eliminate artifacts associated with transmission and fluorescence measurements. Examples include crystalline GexSi1-x alloys, amorphous GaAs and Cu and Au nanocrystals in SiO2. In general, thin films of several microns thickness were first formed on bulk substrates then EXAFS samples were fabricated by separating the thin film and substrate. For transmission measurements, thin films were stacked together to yield the optimum absorption while sample inhomogeneity, non-uniformity and non-continuity were readily eliminated. For fluorescence measurements, scattering/diffraction from the substrate was eliminated and stacking the thin films together increased the areal concentration of the absorber. The use of such techniques to fabricate EXAFS samples yielded a significant increase in accessible photo-electron wave number range and hence more accurate structural parameter determinations.

Authors:
; ; ;  [1];  [2]
  1. Department of Electronic Materials Engineering, Australian National University, Canberra (Australia)
  2. Australian Synchrotron Research Program, Australian Nuclear Science and Technology Organisation, Menai (Australia)
Publication Date:
OSTI Identifier:
21054776
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 882; Journal Issue: 1; Conference: XAFS13: 13. international conference on X-ray absorption fine structure, Stanford, CA (United States), 9-14 Jul 2006; Other Information: DOI: 10.1063/1.2644701; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION SPECTRA; ABSORPTION SPECTROSCOPY; AMORPHOUS STATE; ELECTRONS; ETCHING; FABRICATION; FINE STRUCTURE; FLUORESCENCE; GALLIUM ARSENIDES; GERMANIUM ALLOYS; NANOSTRUCTURES; SEMICONDUCTOR MATERIALS; SILICON ALLOYS; SILVER; SUBSTRATES; THIN FILMS; X-RAY SPECTRA; X-RAY SPECTROSCOPY

Citation Formats

Ridgway, M. C., Glover, C. J., Kluth, P., Johannessen, B., and Foran, G. J.. Novel Preparation Methods for the Fabrication of Thin-Film EXAFS Samples. United States: N. p., 2007. Web. doi:10.1063/1.2644701.
Ridgway, M. C., Glover, C. J., Kluth, P., Johannessen, B., & Foran, G. J.. Novel Preparation Methods for the Fabrication of Thin-Film EXAFS Samples. United States. doi:10.1063/1.2644701.
Ridgway, M. C., Glover, C. J., Kluth, P., Johannessen, B., and Foran, G. J.. Fri . "Novel Preparation Methods for the Fabrication of Thin-Film EXAFS Samples". United States. doi:10.1063/1.2644701.
@article{osti_21054776,
title = {Novel Preparation Methods for the Fabrication of Thin-Film EXAFS Samples},
author = {Ridgway, M. C. and Glover, C. J. and Kluth, P. and Johannessen, B. and Foran, G. J.},
abstractNote = {Thin-film EXAFS samples have been fabricated using semiconductor-processing and wet-chemical etching techniques to eliminate artifacts associated with transmission and fluorescence measurements. Examples include crystalline GexSi1-x alloys, amorphous GaAs and Cu and Au nanocrystals in SiO2. In general, thin films of several microns thickness were first formed on bulk substrates then EXAFS samples were fabricated by separating the thin film and substrate. For transmission measurements, thin films were stacked together to yield the optimum absorption while sample inhomogeneity, non-uniformity and non-continuity were readily eliminated. For fluorescence measurements, scattering/diffraction from the substrate was eliminated and stacking the thin films together increased the areal concentration of the absorber. The use of such techniques to fabricate EXAFS samples yielded a significant increase in accessible photo-electron wave number range and hence more accurate structural parameter determinations.},
doi = {10.1063/1.2644701},
journal = {AIP Conference Proceedings},
number = 1,
volume = 882,
place = {United States},
year = {Fri Feb 02 00:00:00 EST 2007},
month = {Fri Feb 02 00:00:00 EST 2007}
}
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