Applications of Microbeams Produced by Tapered Glass Capillary Optics

Abstract

Production of ion microbeams using tapered glass capillary optics was introduced more than 10 years ago. This technique has drawn attention in terms of both its peculiar transmission features and application to ion beam analysis. The transmission mechanism based on a self-organized charge-up process for keV-energy ions was observed for the first time in an experiment using a multitude of nanometer-sized capillaries in a polymer foil. The same mechanism can be seen for the transmission of keV ions through a single tapered glass capillary. The transmission experiments with keV ions showed a delayed transmission, focusing effects, guiding effects, and formation of microbeams. Experiments using MeV-energy ions always aim at applications of microbeam irradiation for material analysis, surface modification, cell surgery, and so on. In this article, the applications of MeV ion microbeams, including the fabrication method of the glass capillary, are reviewed, as well as the experimental and theoretical studies for the transmission mechanisms of keV/MeV ions.