CLUSTER ION EMISSION IN THE INTERACTION OF SLOW HIGHLY-CHARGED IONS WITH SURFACES

Cluster ion emission from a variety of surfaces upon impact of highly charged ions is investigated by time-of-flight secondary ion mass spec trometry. The yield of cluster ions as a function of cluster size for SiO2 and C-84 surface follow a power law decline with exponent approac hing the -2 limit of the ''equilibrium': and ''shock wave'' cluster em ission models. While the decline of the cluster ion emission with clus ter size is an exponential decay for highly oriented pyrolytic graphit e upon Th70+ impact, the decline is more gradual than for Cs1+ impact, such that at C-16 the relative cluster yield is 1000 times higher.