CLUSTER ION SOURCES

Clusters from gases as well as from metal vapors can be obtained from an expanding nozzle flow with the appropriate set of flow field conditions, characterized by a condensation scaling parameter GAMMA*. Cluster ion beams are characterized by a low specific charge. Accelerated cluster ion beams allow formation of energetic particle beams in the interesting range of 0.01-10 keV/atom, and the specific characteristics of cluster ion beams have led to new applications in science and technology. In this paper a status report on clusters and cluster ions from nozzle sources is given. As example the construction and results of a source for high-intensity silver cluster beams to be used for thin film formation are described.