ABSTRACTAtoms are gas discharge sputtered from a solid target. They are condensed to form clusters using the gas aggregation technique. An intense beam of clusters of all solid materials can be obtained. Up to 80 % of the clusters can be ionised without using additional electron impact ionisation. Total deposition rates vary between 1 and 1000 Å per second depending on cluster diameter, which can be varied between 3 and 500 nm. Thin films of Al, Cu, and Mo have been produced so far. For non accelerated beams a weakly adhering mostly coulored deposit is obtained. Accelerating the cluster ions this changes to a strongly adhering film, having a shiny metallic appearance, and a very sharp and plane surface as seen in an electron microscope. The advantages compared to Kyoto ICB-method are: easy control of the cluster size, no electron impact ionisation, high degree of ionisation, and sputtering is used instead of thermal evaporation, which allows the use of high melting point materials.
Electron-impact ionisation of Wq+ ions with 1 ⩽ q ⩽ 19
