Quantitative analysis of overlapping XPS peaks by spectrum reconstruction: determination of the thickness and composition of thin iron oxide films

Abstract

The composition and thickness of thin iron oxide films on polycrystalline pure iron were evaluated from Fe 2p spectra as measured by x‐ray photoelectron spectroscopy. To this end the experimental spectra were reconstructed from reference spectra of the constituents Fe0, Fe2+ and Fe3+. The background contributions in the spectra owing to inelastic scattering of signal electrons were calculated from the depth distributions of these constituents and their reference spectra. In the reconstruction procedure the film thickness and the concentrations of Fe2+ and Fe3+ in the oxide film were used as fit parameters. The values obtained for the oxide film thickness were compared with thickness values determined from the intensity of the corresponding O 1s spectra and with thickness values resulting from ellipsometric analysis. The sensitivity of the reconstruction procedure with regard to film thickness and film composition was tested. © 1998 John Wiley & Sons, Ltd.

Analysis of XPS spectra of Fe2+ and Fe3+ ions in oxide materials

“…The quantitative analysis of the oxidation states of iron in the thin films has been carried out by Graat and Somers [3,4] using Tougaard's inelastic scattering theory. They measured the XPS Fe 2p spectra of the pure components Fe 0 from sputter-cleaned iron metal, Fe 2+ from sputter-cleaned FeO powder and Fe 3+ from Fe 2 O 3 powder.…”

“…It has been shown in previous studies that the peak positions of Fe 2p 1/2 and Fe 2p 3/2 depend on the ionic states of Fe [2][3][4][5][6][7]. The positions of the satellite peaks for the Fe 2p 1/2 and Fe 2p 3/2 peaks are also very sensitive to the oxidation states and these peaks have been used for qualitatively determining the ionic states of iron.…”

Natural Oxidation of thin Fe Films on V Buffer Layer

“…It has been shown in previous studies [1,[9][10][11][12][13][14][15] that the peak positions of Fe 2p 1/2 and Fe 2p 3/2 depend on the ionic states of Fe. The positions of the satellite peaks for the Fe 2p 1/2 and Fe 2p 3/2 peaks are also very sensitive to the oxidation states and these peaks have been used for qualitatively determining the ionic states of iron.…”

Effect of the presence of alloying elements in interstitial-free and low-carbon steels on their surface composition after annealing in reducing atmospheres (dew point=−30 °C)

“…The Fe2p 3/2 spectra show two very intense components at binding energies of 709.7 and 711.0 eV, which may be associated with the presence of iron in the form of Fe 2ϩ and Fe 3ϩ , respectively. [41,42,43] The intensity of the component associated with Fe 0 (706.7 eV) is practically negligible. Figures 4(a) through (c) show the Fe2p 3/2 highresolution XPS spectra obtained on the surface of the LC steels after cold rolling.…”