Tom Wirtz oral presentation (PB1-Tue4-1-1)
SIMS performed on the Helium Ion Microscope: new prospects for highest spatial resolution imaging and correlative microscopy
Luxembourg Institute of Science and Technology (LIST), 41, rue du Brill, 4422 Belvaux, Luxembourg
The Helium Ion Microscope (HIM) has become an ideal tool for imaging and nano-patterning . Imaging with helium ions leads to resolutions of 0.5 nm for secondary electron (SE) based imaging, while structures with sub 20 nm feature sizes may be rapidly patterned using Ne. Despite these advantages, the analysis capability of the instrument is currently limited. At beam energies of 35 keV helium or neon ions do not lead to the emission of characteristic X-rays from a sample. While some compositional information can be obtained from back scattered helium, identifying elemental information is more difficult.
In order to add nano-analytical capabilities to the HIM, we have developed a Secondary Ion Mass Spectrometry (SIMS) system specifically designed for the Zeiss ORION NanoFab HIM [2-4]. In SIMS, the typical interaction volume between the impinging ion beam and the sample is around 10 nm in the lateral direction. As the probe size in the HIM is substantially smaller (both for He and Ne), the lateral resolution on the integrated HIM-SIMS is limited only by fundamental considerations and not, as is currently the case on commercial SIMS instruments, the probe size [4,5]. We have demonstrated that our instrument is capable of producing elemental SIMS maps with lateral resolutions down to 12 nm [4-6]. Furthermore, HIM-SIMS opens the way for in-situ correlative imaging combining high resolution SE images with elemental and isotopic ratio maps from SIMS [4,5]. This approach allows SE images of exactly the same zone analysed with SIMS to be acquired easily and rapidly, followed by a fusion between the SE and SIMS data sets.
 G. Hlawacek, A. Gölzhäuser, Helium Ion Microscopy, Springer, 2017
 T. Wirtz et al., Appl. Phys. Lett. 101 (4) (2012) 041601-1-041601-5
 L. Pillatsch et al., Appl. Surf. Sci. 282 (2013) 908-913
 T. Wirtz et al., Helium Ion Microscopy, ed. G. Hlawacek, A. Gölzhäuser, Springer, 2017
 T. Wirtz et al., Nanotechnology 26 (2015) 434001
 P. Gratia et al., J. Am. Chem. Soc. 138 (49) (2016) 15821–15824