A comparison of absolute yields of excited neutrals and positive ions from ion-bombarded surfaces

The yields of excited neutral atoms and of positive ions sputtered from Ar⁺ ion-bombarded surfaces of Si and Ni under saturation oxygen coverage have been examined. By determining the transmission of the optical system and of the mass spectrometer used for these measurements, the absolute yields of the excited and ionized species were estimated. The results show that absolute photon yields are lower than the ion yields and their implications on the process of ion and excited atom formation in sputtering are discussed.