| AVS 66th International Symposium & Exhibition | |
| Advanced Ion Microscopy and Ion Beam Nano-engineering Focus Topic | Thursday Sessions |
| Session HI+NS-ThA |
| Session: | Emerging Ion Sources, Optics, and Applications |
| Presenter: | Jabez McClelland, National Institute of Standards and Technology (NIST) |
| Authors: | J.J. McClelland, National Institute of Standards and Technology (NIST) J.R. Gardner, National Institute of Standards and Technology (NIST) W.R. McGehee, National Institute of Standards and Technology (NIST) A. Schwarzkopf, zeroK NanoTech Corp. B.J. Knuffman, zeroK NanoTech Corp. A.V. Steele, zeroK NanoTech Corp. |
| Correspondent: | Click to Email |
Ionization of laser-cooled atoms has emerged as a new approach to creating high brightness ion sources for applications such as focused ion beam (FIB) microscopy, milling, and secondary-ion mass spectrometry (SIMS). Conventional sources, such as the Ga liquid metal ion source (LMIS) or the gas field ionization source (GFIS), attain brightness by emitting from a very sharp tip. In contrast, cold atom sources attain high brightness through reducing the transverse velocity spread of the ions. With the ultracold, microkelvin-range temperatures achievable with laser cooling, the corresponding velocity spread can lead to a brightness significantly higher than typical LMIS values. Moreover, the phase-space shape of the emittance of the source – narrow in velocity, wide in space – brings new opportunities for ion optical design. For example, high currents can be obtained without the high current density present in sharp tip sources. This can result in reduced Coulomb effects, such as increased emittance and broadened energy spread (Boersch effect). Other advantages of this type of source include insensitivity to contamination, access to new ionic species, inherent isotopic purity, and fine control over emission, down to the single ion level. To date, sources have been demonstrated with Cr,1 Li,2 Rb,3 and Cs4,5 ions, realizing novel species and nanometer-scale spot sizes. In this talk I will review progress in the field and discuss recent developments in Li ion sources and applications.
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