Quest for high brightness, monochromatic noble gas ion sources

Focused ion-beam (FIB) machines are key tools for state-of-the art sample preparation in electron microscopy, for characterization and repair in material sciences, for the semiconductor industry and for nanotechnology in general. Liquid-metal ion sources (LMIS) are widely used in FIB machines because they meet the minimum ion source requirements such as source brightness and reliability. However, in FIB machines, noble gas ion sources are favorable for sputtering, beam-induced etching and deposition, because the implanted ions do not change the electrical behavior of the substrate significantly. There are several efforts by various researchers to develop noble gas ion sources that can be used in FIB machines instead of LMIS. The gas ion sources could not meet the minimum ion source requirements. Therefore, LMIS are still a popular choice among FIB machine users. This review article takes a critical look at the reported efforts in the literature to develop noble gas ion sources for FIB machines. (c) 2005 American Vacuum Society.