ELECTRON-EMISSION FROM SLOW NE9+ IONS IMPINGING ON AN AL SURFACE

Low-energy electrons emitted during the interaction of Ne9+ ions with an Al surface were measured. The projectile energy was 4.5 keV while t he observation angle was varied between 10 degrees and 75 degrees. The election measurements are reliable at energies as low as a few eV. Th e experimental data are compared with calculations for the secondary e lectron emission caused by Auger transitions below the surface based o n transport equation formalism and a simulation for electrons emitted due to autoionization above the surface following the classical over-t he-barrier model. This comparison is a first attempt to study the diff erent electron emission processes produced by the interaction of Ne9with Al especially for low electron energies. (C) 1998 Elsevier Scienc e B.V.