Automated peak fitting of XPS spectrum using information criteria

Abstract

We developed and implemented a fully automated method to perform X-ray photoelectron spectroscopy (XPS) spectral analysis based on the active Shirley method and information criteria. Our method searched many initial fitting models by changing the degree of smoothing, and obtained many fitting models after peak parameter optimization. The goodness of those models was evaluated using the Bayesian information criterion (BIC). As a result of applying this algorithm to measured XPS spectra, we found that using the BIC, a simple model with reasonably good agreement and a small number of peaks was selected. The model selected by the BIC was close to the results of peak fitting performed by XPS analysis experts.