Focused ion beam microscopy has a number of advantages over electron microscopy, such as decreased penetration depth, smaller interaction volume, and the possibility of reaction-based imaging.  However, ion sources of appropriate species with sufficiently low emittance, high brightness, and narrow energy spread are difficult to realize.  A magneto-optical trap ion source (MOTIS) has the promise of producing high quality beams of low-mass ionic species that are well suited for microscopy without sample damage from sputtering [1].  The MOTIS uses photoionized laser-cooled neutral atoms to create a low emittance, high brightness, narrow-energy-spread beam of ions whose calculated ion optical properties are comparable to or better than those of liquid metal ion sources.  The MOTIS paradigm can be extended to create ion sources from any atomic species that can be laser-cooled, e.g., Li, Na, K, Rb, Cs, Fr, Mg, Ca, Sr, He, Ne, Ar, Kr, Xe, Al, Ag, Cr, Er, Cd, Hg, and Yb.  This flexibility would allow the atomic species of the source to be tailored to the specific application: microscopy with light ions, milling with heavy ions, and nanoscale implantation of a variety of elements. We report on the construction and performance of a MOTIS-technology-based lithium ion source.

 [1] J. L. Hanssen, S. B. Hill, J. Orloff, and J. J. McClelland, Nano Letters 8, 2844 (2008).