Question

How can you differentiate Auger Peaks from photoelectron peaks in an XPS spectrum? Explain the theory.

Answer 1

In XPS spectra, both photoelectron and Auger elecron peaks are present. To distinguish between them we can use different source energies and compare them. The photoelectron Kinetic energy depends upon the nature of source while the Auger electron Kinetic energy is independent of nature of source. When we change the source, we change the excitation energy. This will produce peaks. These peaks will be such that some of them are shifted and some of them are not. The Auger peaks move to different Binding Energy whereas the photoelectron peaks remain at same Binding Energy.