Non-destructive compositional depth profile analysis by hard x-ray photoelectron spectroscopy

The photoemission spectroscopies play a preponderant role in the study of the electronic and compositional properties of solids. However, in standard laboratory conditions the reduced escape depth, added to low photon flux of conventional sources, make inaccessible depth profile information in a non-destructive way. In particular, the buried interfaces are not accessible for the great majority of the surface science non-destructive chemical, compositional and electronic techniques. An effective way to overcome this drawback is increasing the probing depth by analyzing electrons with a higher kinetic energy, i.e., extending the XPS to the Hard X-ray regime. Hard X-ray PhotoElectron Spectroscopy (HAXPES) is becoming an extremely powerful tool for chemical, compositional and electronic characterization of bulk and buried interfaces. A potential application of HAXPES is the determination of nondestructive compositional depth profiles in the tens nanometers scale. A methodology based on HAXPES and X-Ray Diffraction is presented through this manuscript for the determination of non-destructive compositional depth profiles.