A unique aspect of the Ionized Cluster Beam (ICB) thin film deposition method is that material is deposited as ionized, accelerated atom clusters. Results of one laboratory suggest that a wide range of beneficial film formation effects can be attributed to the clusters, reported to average 1000 atoms in size. We present two cluster measurement methods here to investigate these claims. In the first, the depositing beam passes through an ionizer, a slit and an electrostatic deflection field. An undeflected neutral deposit and an ionized deflection deposit form on a single crystal silicon substrate. The ratio of atom flux to charge flux in the deflected deposit is equal to the number of atoms per singly charged cluster. In the second method, a low amplitude 10 KHz signal modulates the electrostatic deflection field. The phase shift between the modulation voltage and the measured substrate current yields particle velocity from which mass can be obtained. We have confirmed the presence of small, three atom gold clusters.
