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PubMed · 8652886

Energy-filtered high-resolution electron microscopy and composition-sensitive imaging.

Z L Wang
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Abstract

Energy-filtered electron imaging is one of the future directions of high-resolution electron microscopy (HREM). In this paper, characteristics and applications of energy-selected HREM are illustrated. Image contrast can be dramatically improved with the use of an energy filter. High-resolution chemical-sensitive imaging using ionization edge loss electrons is demonstrated in studies on Ni/Ti and A1/Ti multilayer thin films. It has been shown that the spatial resolution of energy-selected ionization edge electron images is dominated by the signal-to-noise ratio. Experimental parameters which may be selected to improve the signal-to-noise ratio are discussed. It is pointed out that since the width of the energy-selecting window is small, the energy-filtered ionization edge electron image is sensitive to the specimen composition, but the calculation of the specimen composition based on the energy-filtered images relies on the integrated ionization cross-sections which are largely determined by the solid state effects. Therefore, the energy-filtered ionization image should be referred as composition-sensitive image rather than compositional image.

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Z L Wang. 1996-02-15. Energy-filtered high-resolution electron microscopy and composition-sensitive imaging.. https://doi.org/10.1002/(sici)1097-0029(19960215)33%3A3%3C279%3A%3Aaid-jemt5%3E3.0.co%3B2-l

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