X-Ray Photoelectron Spectroscopy (XPS)

Abstract

As seen in figure 1, photoejection of a core electron (instead of radiationless secondary electron emission in AES, fig. 3) occurs in XPS. The kinetic energy of the photoejected core electrons is defined as KE = hv BE + phi, where hv is the energy of the incoming x-ray photons, BE is the binding energy of the photoejected electrons, and phi is the spectrometer work function. The binding energy (BE) of the core electrons allows for specific elemental characterization of samples as the electronic structure of each element is unique. Auger electron emission occurs readily in XPS as they are mutually exclusive processes, meaning that the individual probabilities of each process occurring must sum to one.