Auger Electron Angular Distributions from Surfaces: Direct Comparison with Isoenergetic Photoelectrons

Angular distribution patterns of Auger electrons and of photoelectrons from a Cu (001) surface were measured at the same electron kinetic energy. These measurements reveal that the low kinetic energy angular distributions for Cu Auger electrons and Cu 3 p 3/2 photoelectrons differ substantially. This direct comparison between the photoelectron and Auger electron angular distributions demonstrates that, in some circumstances, the Auger process produces a complicated source wave whose nature must be explored before Auger angular distributions can be used for surface structure analysis.