Optimal ADF STEM imaging parameters for tilt-robust image quantification

K E MacArthur; A J D'Alfonso; D Ozkaya; L J Allen; P D Nellist

doi:10.1016/j.ultramic.2015.04.010

Optimal ADF STEM imaging parameters for tilt-robust image quantification

Ultramicroscopy. 2015 Sep:156:1-8. doi: 10.1016/j.ultramic.2015.04.010. Epub 2015 Apr 28.

Authors

K E MacArthur¹, A J D'Alfonso², D Ozkaya³, L J Allen², P D Nellist⁴

Affiliations

¹ Department of Materials, University of Oxford, Parks Road OX1 3PH, UK. Electronic address: katherine.macarthur@materials.ox.ac.uk.
² School of Physics, University of Melbourne, Parkville, Victoria 2010, Australia.
³ Johnson Matthey Technology Centre, Blounts Court Road, Sonning Common, Reading RG4 9NH, UK.
⁴ Department of Materials, University of Oxford, Parks Road OX1 3PH, UK.

PMID: 25957734
DOI: 10.1016/j.ultramic.2015.04.010

Abstract

An approach towards experiment design and optimisation is proposed for achieving improved accuracy of ADF STEM quantification. In particular, improved robustness to small sample mis-tilts can be achieved by optimising detector collection and probe convergence angles. A decrease in cross section is seen for tilted samples due to the reduction in channelling, resulting in a quantification error, if this is not taken into account. At a smaller detector collection angle the increased contribution from elastic scattering, which initially increases with tilt, can be used to offset the decrease in the TDS signal.

Keywords: Electron channelling; Quantitative ADF; Sample tilt.

Publication types

Research Support, Non-U.S. Gov't