Correlation analysis with measurement conditions and peak structures in XPS spectral round-robin tests on MnO powder sample

Abstract

Spectral measurements provide valuable information on the electronic states and crystal structures of materials. In particular, X-ray photoelectron spectroscopy (XPS) can facilitate the analysis of the chemical-bond states of the surfaces of materials. In the analysis of XPS spectra, the spectrum to be measured is typically compared to a reference spectrum measured from a known single-phase sample. Therefore, establishing a reference spectral database is imperative. In this study, round-robin tests (RRT) of XPS spectra are performed to obtain recommended XPS reference spectra and develop appropriate measurement conditions, including preprocessing procedures. Determining the variations in peak structures between equipment- and sample-derived spectral shapes and quantitatively discussing them through RRT of XPS spectra are challenging. Therefore, an analysis method that automatically determines the above-mentioned variations and extracts the sample-derived common spectral structures is developed in this study. This paper presents a new approach to the quantitative analysis of round-robin XPS spectral tests. The required common peak structure, a new definition of the XPS reference spectrum, is obtained. Further, a correlation between the variability of deviations in the spectral data of the RRT and the measurement condition and XPS measurement equipment used is determined. Such a framework is essential for standardizing XPS spectra and expanding the XPS reference spectral database.