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X-Ray Microanalysis in the STEM

Published online by Cambridge University Press:  02 July 2020

D. B. Williams  and
M. Watanabe
D. B. Williams
Affiliation:
Department of Materials Science and Engineering, Lehigh University, Bethlehem, PA18015, USA
M. Watanabe
Affiliation:
Research Laboratory for High Voltage Electron Microscopy, Kyushu University, Fukuoka 812-8581, Japan
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Extract

Commercial TEM/STEMs are ill designed for quantitative X-ray microanalysis of thin foils. There have been no fundamental advances in their design since the first instruments appeared in the mid- 1970s. These instruments had thermionic sources with useful probe sizes of ∼10 nm, small (∼ 0.1 sr) detector collection angles, illumination systems giving serious levels of stray radiation, substantial hydrocarbon and water-vapor contamination due to the poor vacuum (∼10-5Pa) and sliding o-ring seals on unstable side-entry goniometer stages. The instruments lacked a direct measure of the probe current at the specimen. Often a 60 s accumulation time resulted in enough drift or contamination that the microanalysis was not trustworthy and spatial resolution was compromised. Today's modern TEM/STEMs, apart from replacement of thermionic source with a FEG, are little better.

Dedicated STEMs however, have invariably offered better X-ray performance. The first VG HB 5 DSTEM became available, also in the 1970s, and the X-ray performance improved through to the latest design (the VG HB 603) in the mid-1990s.

Type
The Theory and Practice of Scanning Transmission Electron Microscopy
Information
Microscopy and Microanalysis , Volume 6 , Issue S2: Proceedings: Microscopy & Microanalysis 2000, Microscopy Society of America 58th Annual Meeting, Microbeam Analysis Society 34th Annual Meeting, Microscopical Society of Canada/Societe de Microscopie de Canada 27th Annual Meeting, Philadelphia, Pennsylvania August 13-17, 2000 , August 2000 , pp. 112 - 113
Copyright
Copyright © Microscopy Society of America

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References

1.Lyman, C. E. et al. J. Microsc. 176 (1994) 85.CrossRefGoogle Scholar
2.Carpenter, D. T. et al., Microscopy and Microanalysis 5 (1999) 254.CrossRefGoogle Scholar
3.Watanabe, M. and Williams, D. B., Ultramicroscopy 78 (1999) 89.CrossRefGoogle Scholar
4.Wollman, D. A. et al. J. Microsc. 188 (1997) 196.CrossRefGoogle Scholar
5.Lupini, A. R. and Krivanek, O. L. Electron Microscopy -1998, Cancun (1998) 59.Google Scholar
6.Watanabe, M. et al., Ultramicroscopy 65 (1996) 187.CrossRefGoogle Scholar
7.Boon, G., PhD Thesis Technische Universiteit Eindhoven 2000 (ISBN 90-386-2781-5)Google Scholar
8. Work supported through NSF DMR-9972670Google Scholar