On the temperature dependence of the electric characteristics and mass spectra of liquid metal alloy ion sources

This paper reports on an extensive study of the characteristics of AuGeSi and CoNd liquid metal alloy ion sources (Focused Ion Beams From Liquid Metal Ion Sources, Research Studies Press, Taunton, Somerset, UK, 1991). Such characteristics include current–voltage curves and ion beam mass spectra. A careful investigation has been undertaken where the emitter temperature is the main variable experimental parameter. Theoretical models, or theoretical attempts in certain cases, tend to support the experimental results. The experimental results, in conjunction with existing theories, suggest that simply for reasons of self-consistency two mechanisms must be operative for the production of doubly-charged ions from the AuGeSi source: direct field-evaporation and post-ionisation.