Auger electron angular distributions from surfaces: Direct comparison with isoenergetic photoelectrons

Angular distribution patterns of Auger electrons and of photoekctrons 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 3p3/2 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.