XpsVariableKinetic

X-ray photoelectron spectroscopy (XPS), also known as ESCA (electron spectroscopy for chemical analysis) is a surface analysis technique which provides both elemental and chemical state information virtually without restriction on the type of material which can be analysed. It is a relatively simple technique where the sample is illuminated with X-rays which have enough energy to eject an electron from the atom. These ejected electrons are known as photoelectrons. The kinetic energy of these emitted electrons is characteristic of the element from which the photoelectron originated. The position and intensity of the peaks in an energy spectrum provide the desired chemical state and quantitative information. The surface sensitivity of XPS is determined by the distance that that photoelectron can travel through the material without losing any kinteic energy. These elastiaclly scattered photoelectrons contribute to the photoelectron peak, whilst photoelectrons that have been inelastically scattered, losing some kinetic energy before leaving the material, will contribute to the spectral background.