Chemical State Quantification of X-ray Auger Electron Spectrum with Top-Hat Filtering

Abstract

The chemical state quantification of elements, especially transition metals and their compounds from X-ray Auger electron spectrum, is generally difficult due to the complexity of spectra resulting from peak asymmetries and overlapped binding energies. Moreover, background shape which contains information on surface contamination and roughness affects comparability of spectral fitting data on the element of interest. To promote practical use of spectral fitting for the chemical state quantification, the top-hat filtering (THF) was applied to Cu LMM Auger electron spectra. It was found that the THF suppressed the difference of background shapes derived from surface contamination and that oxidation states of Cu was quantified plausibly by least square fitting of standard spectra. Thus, it is suggested that the combination of the THF and least square fitting is a practical method for the chemical state quantification of X-ray Auger electron spectrum.