EMISSION CHARACTERISTICS OF AN AU-GE LIQUID-METAL ION-SOURCE

A liquid metal ion source (LMIS), based on an Au 27 at. % Ge eutectic alloy was investigated and the mass spectrum and angular distributions of different ion species determined. A strong influence of the total emission current and the angle with respect to source axis on the mass spectrum was observed. The process of ion emission from the ion sourc e was simulated and the virtual source size, beam spot size, and the e nergy and angular distributions of the ions estimated. The effect on t he emission characteristics of Coulomb interaction between ions was al so investigated. (C) 1998 Elsevier Science Ltd. All rights reserved.