X-ray Photoelectron Spectroscopy (XPS)

XPS analysis is a surface-sensitive quantitative spectroscopic technique that typically measures the top 0-10 nm of a sample surface. Elements from Lithium (Li) upwards in the periodic table can be measured.

Measurements are carried out with a Thermo K-Alpha XPS. For the measurements, the sample has to be placed in ultra-high vacuum.

XPS technique can be used to measure elemental composition of surface. The atomic concentrations of the sample are determined. This information is then used to derive the empirical formula of pure materials. It can be used to determine the chemical states of each element in the material. Line profiling and mapping across the top surface can also be realized.