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Improvements in the X-Ray Analytical Capabilities of a Scanning Transmission Electron Microscope by Spherical-Aberration Correction

Published online by Cambridge University Press:  11 October 2006

M. Watanabe ,
D.W. Ackland ,
A. Burrows ,
C.J. Kiely ,
D.B. Williams ,
O.L. Krivanek ,
N. Dellby ,
M.F. Murfitt  and
Z. Szilagyi
M. Watanabe
Affiliation:
Department of Materials Science and Engineering/Center for Advanced Materials and Nanotechnology, Lehigh University, Bethlehem, PA 18015, USA
D.W. Ackland
Affiliation:
Department of Materials Science and Engineering/Center for Advanced Materials and Nanotechnology, Lehigh University, Bethlehem, PA 18015, USA
A. Burrows
Affiliation:
Department of Materials Science and Engineering/Center for Advanced Materials and Nanotechnology, Lehigh University, Bethlehem, PA 18015, USA
C.J. Kiely
Affiliation:
Department of Materials Science and Engineering/Center for Advanced Materials and Nanotechnology, Lehigh University, Bethlehem, PA 18015, USA
D.B. Williams
Affiliation:
Department of Materials Science and Engineering/Center for Advanced Materials and Nanotechnology, Lehigh University, Bethlehem, PA 18015, USA
O.L. Krivanek
Affiliation:
NION Co., Kirkland, WA 98033, USA
N. Dellby
Affiliation:
NION Co., Kirkland, WA 98033, USA
M.F. Murfitt
Affiliation:
NION Co., Kirkland, WA 98033, USA
Z. Szilagyi
Affiliation:
NION Co., Kirkland, WA 98033, USA
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Abstract

A Nion spherical-aberration (Cs) corrector was recently installed on Lehigh University's 300-keV cold field-emission gun (FEG) Vacuum Generators HB 603 dedicated scanning transmission electron microscope (STEM), optimized for X-ray analysis of thin specimens. In this article, the impact of the Cs-corrector on X-ray analysis is theoretically evaluated, in terms of expected improvements in spatial resolution and analytical sensitivity, and the calculations are compared with initial experimental results. Finally, the possibilities of atomic-column X-ray analysis in a Cs-corrected STEM are discussed.

Keywords

spherical-aberration corrector (Cs-corrector)probe formationspatial resolutionminimum mass fractionminimum detectable massquantitative thin-film X-ray analysisζ(zeta)-factor methodgrain-boundary segregation
Type
Research Article
Information
Microscopy and Microanalysis , Volume 12 , Issue 6: Special Issue: Frontiers of Electron Microscopy in Materials Science , December 2006 , pp. 515 - 526
Copyright
© 2006 Microscopy Society of America

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References

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