Kinetic energies of excited atoms ejected from ion-bombarded surfaces

The decay of photon yield from sputtered excited atoms as a function of the perpendicular distance from an ion-bombarded surface has been measured for four particular transitions using an intensified silicon intensifier target (ISIT) detector and an optical multichannel analyzer (OMA) with 512 channels. This experimental approach has resulted in greatly improved spatial resolution than previous attempts, making it possible to examine in detail the decay from departing atoms close to the target surface, thereby circumventing to some extent the long-lived cascade contribution. The kinetic energies derived are compared with previous measurements and their implication to the excitation process in sputtering is discussed.