Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9818086 | Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms | 2005 | 5 Pages |
Abstract
We present results of a study of He+ neutralisation on clean and oxygen covered Al(1 1 1). For clean Al(1 1 1) we find a small ion fraction which rapidly increases with increasing ion energy attaining about (0.4 ± 0.1)% at 4 keV. The overall behaviour is quite different from that observed on previously studied Ag surfaces and is attributed to reionisation processes, a conclusion supported by measurements using He atoms. When O2 is adsorbed onto Al(1 1 1) at room temperature, we observe a rapid increase in the ion fraction, which attains a broad plateau for exposures higher than about 50 L. Experiments with incident He atoms lead to an ion fraction that is smaller, indicating that in this case a substantial fraction of ions is due to survival of incident ions. We attribute these changes to a decrease of the Auger neutralisation rates on the oxidic surface.
Related Topics
Physical Sciences and Engineering
Materials Science
Surfaces, Coatings and Films
Authors
T. Kravchuk, V.A. Esaulov, A. Hoffman, R.C. Monreal,