Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

Presently Focused Ion Beam (FIB) processing is dominated by gallium Liquid Metal Ion Sources (LMIS). But, beside new developments in this field like He/Ne ion microscopes or Xe-FIBs many applications in the µm- or nm range could benefit from ion species other than gallium or noble gases: local ion implantation, ion beam mixing, ion beam synthesis or even Focused Ion Beam Lithography. Therefore Liquid Metal Alloy Ion Sources (LMAIS) represent a promising alternative to expand the remarkable application fields for FIB [1,2]. Simple switching between the certain ion species using an ExB mass filter can be applied to change significantly the physical and chemical nature of the resulting nanostructures -in other words the electrical, optical, magnetic and mechanic properties. This offers a large application potential which can be tuned by choosing a well suited LMAIS. Now nearly half of the elements of the Periodic Table are available in FIB technology. Main properties of a modern LMAIS are long life-time, high brightness and stable ion current. This contribution will cover the physical basics and experimental results of LMAIS, their physical properties (I-V characteristics, energy spread) and questions of the preparation technology using elementary as well as binary and ternary alloys as source material. Furthermore selected applications will be presented to underline the impact of these sources in modern nanotechnology by highly focused ion beams. Recent developments could make these sources feasible for nano patterning issues as an alternative technology more in research than in industry.

References
[1] L. Bischoff: “Application of mass-separated focused ion beams in nano-technology”, Nucl. Instr. Meth. B 266 (2008), 1846. DOI:10.1016/j.nimb.2007.12.008
[2] L. Bischoff, P. Mazarov, L. Bruchhaus, and J. Gierak: „Liquid Metal Alloy Ion Sources - An Alternative for Focused Ion Beam Technology” , Appl. Phys. Rev. 3 (2016) 021101-1-30
[3] L. Bischoff and Ch. Akhmadaliev: “An alloy liquid metal ion source for lithium”, J. Phys. D: Appl. Phys. 41 (2008) 052001. DOI:10.1088/0022-3727/41/5/052001