Correspondence Analysis for Quantification in Electron Energy Loss Spectroscopy and Imaging

Abstract:

Electron energy loss spectroscopy (EELS) is a technique to investigate the physical properties of material. Using this technique it is possible to detect the presence of a specific element in a specimen. When used in combination with an electron microscope, energy filtered images may be obtained, which in principle may be used to quantify the local element concentration. This involves a process of background correction, conventionally performed assuming a specific parametric behavior of the spectral intensity as a function of electron energy loss. In this article a parameter-free method is described for background correction based on the formalism of correspondence analysis. Such a method may be used in parts of the spectrum where the functional dependence of the spectral intensity is unknown. Use of this method for element detection has been suggested before. This article reports simulation experiments suggesting its suitability for quantitative determination of element distributions and element concentrations.

Keywords

Electron Microscopy - Electron Energy Loss Spectroscopy - Correspondence Analysis - Image Sequences

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