Auger Electron Spectroscopy (AES) is a surface-sensitive analytical technique used to determine the elemental composition of materials. It works by bombarding a sample with high-energy electrons, which causes the emission of Auger electrons from the surface. The energy of these emitted electrons is measured to identify the elements present in the sample. AES is particularly useful for studying thin films and coatings, as it can analyze layers just a few nanometers thick. The technique provides valuable information about the chemical state and distribution of elements, making it important in fields like materials science, semiconductor manufacturing, and surface chemistry.