Droplet emission from liquid metal ion sources and their disintegration

In recent years there have been several attempts to explain cluster emission from liquid metal ion sources. Droplet disintegration is widely considered as the main mechanism for cluster formation. Since the disintegration process is a critical part of cluster formation, it needs detailed description. Most authors consider ion-induced Rayleigh break-up as the most likely mechanism for droplet disintegration. In this paper we attempt to provide additional understanding of droplet break-up. It can be shown that for low currents considerable disintegration occurs before the accumulated charge reaches the Rayleigh limit. We show that the mechanism for droplet break-up depends on the ion current.