Generation of Ion Nano-Beams with a Gas Field Ion Source

Abstract

With the advent of the super-tip gas field ion source very favourable conditions for generating ion nano-beams have been provided. The basic physical principles for this kind of source are described As a consequence of a very small source emittance of ε ~ 10 -24 m 2 sr ultrabright rare gas ion beams of about 10 16 A/m 2 .sr can be produced. As a further consequence, very narrow probe sizes are obtainable, of d p < 1 nm, with spatial resolutions far below the classical limits of light-optics and even below the novel stimulated-emission-depletion microscopy [STED (microscopy) = stimulated emission depletion (microscopy)] Th. A. Klar, S. W. Hell, Opt. Lett. 24 (1999) 954-956]. Various ion-nanobeam applications are envisaged.