X-Ray Photoelectron Spectrometer (XPS)

X-ray photoelectron spectroscopy (XPS) is the most used surface analytical technique. For the outermost ten nanometers of a material, it provides semi-quantitative elemental compositions and oxidation state or chemical bonding information. XPS can detect any element except hydrogen and helium with a detection limit of about 0.3 atomic percent. Most materials stable in ultrahigh vacuum can be analyzed with little to no sample preparation. Ion-sputtering depth profiling also allows for data to be collected for up to a couple of microns depth.