In addition to the impact on quantitative analysis, information about the depth distribution of elements in the near surface region can often be obtained by visual inspection of the background and quantified using appropriate modeling. The spectral background is also critical when peak fitting is used to determine intensities of overlapping peaks, and the model of background used in this process can impact the results. For the determination of peak area intensities, the background is subtracted from overall signal intensity. Determination of peak intensities requires separation of the photoelectron peak signals from the background on which the peaks rest. Quantitative chemical analysis using XPS requires the assessment of the intensities of the photoemission peaks of the elements detected.
Photoelectron and Auger peaks are central to most of the important uses of x-ray photoelectron spectroscopy (XPS), and thus, they receive the most attention in many types of analysis.
