Quantitative Evaluation of the Chemical State of Copper Oxide in XPS Depth Profiling Data by Simultaneous Analysis with Photoelectron and Auger Electron Peaks

Abstract

Quantitative surface analysis of the chemical state of copper materials is important for understanding the bonding process between copper and different materials. X-ray photoelectron spectroscopy (XPS) is expected to be able to distinguish between 0- to 2-valent copper compounds based on the positions of photoelectron and Auger electron peaks. However, quantitative component analysis of multiphase copper compounds using XPS has been difficult because the difference in chemical shifts between copper with different valences is small and the fine structure of the XPS spectrum varies depending on the copper compound type even for the same valence. In this study, we applied a recently developed technique to simultaneously analyze both Auger and photoelectron peaks automatically and comprehensively in the case of the depth profiling of naturally oxidized copper, and to establish a quantitative evaluation method for the chemical state of copper compounds.