| AVS 60th International Symposium and Exhibition | |
| Atom Probe Tomography Focus Topic | Wednesday Sessions |
| Session AP+AS+EM+MI+TF-WeM |
| Session: | APT Analysis of Semiconductor, Magnetic, and Oxide Materials |
| Presenter: | D.J. Larson, CAMECA |
| Authors: | D.J. Larson, CAMECA B.P. Geiser, CAMECA T.J. Prosa, CAMECA T.F. Kelly, CAMECA |
| Correspondent: | Click to Email |
In the last decade, the applicability of atom probe tomography (APT) has undergone a revolution [1] due to: 1) improved specimen preparation due to focused ion beam milling, 2) improved field of view due to the advent of a local electrode or other ion optical methods, and 3) reinvention of the use of lasers to induce field evaporation. This combination has created challenges in the area of spatial data reconstruction algorithms for APT for two reasons. Firstly, datasets collected at wider field of view are not accurately reconstructed using small angle approximation algorithms. Secondly, heterogeneous specimens containing multiple phases are more likely to yield, which creates challenges in reconstruction due to the non-hemispherical specimen shapes arising from field evaporation.
The most common algorithm for APT data reconstruction has been used with minimal changes for nearly twenty years [2] and has two main limitations: 1) the field evaporated surface is reconstructed as a hemispherical shape and 2) the atomic volume/depth increment is independent of X or Y. This abstract presents recent advances that have been made on APT data reconstruction, particularly in the areas of algorithm development and field evaporation simulation [3]. Various methods of improving APT reconstruction include: 1) post-reconstruction density correction [4], 2) methods which operate within the limits of the hemispherical projection, both pre- and post-reconstruction [5], and 3) methods which remove the hemispherical limitation, primarily based on simulation [6].
1. T. F. Kelly and D. J. Larson, MRS Bull. 37 (2012) 150
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4. X. Sauvage et al., Acta Mater. 49 (2001) 389, F. Vurpillot, A. Cerezo and D. J. Larson, Surf. Int. Anal. 36 (2004) 552, F. DeGeuser et al., Surf. Int. Anal.39 (2007) 268.
5. D. J. Larson et al., J. Microscopy. 243 (2011) 15, F. Vurpillot et al., Ultramicroscopy 111(8) (2011) 1286, B. Gault et al., Ultramicroscopy 111(11) (2011) 1619, D. J. Larson et al., Micro. Microanal. 17(S2) (2011) 740, M. Moody et al., Micro. Microanal. 17 (2011) 226, D. J. Larson et al., Ultramicroscopy 111(6) (2011) 506, B. P. Geiser et al., Micro. Microanal. (2013) in press,
6. D. J. Larson et al., Micro. Microanal. 18(5) (2012) 953, D. Haley et al., J. Microscopy. 244 (2011) 170.