Quantitative elemental mapping at atomic resolution using X-ray spectroscopy

Abstract

Elemental mapping using energy-dispersive x-ray spectroscopy in scanning transmission electron microscopy, a well-established technique for precision elemental concentration analysis at submicron resolution, was first demonstrated at atomic resolution in 2010. However, to date atomic resolution elemental maps have only been interpreted qualitatively because the elastic and thermal scattering of the electron probe confounds quantitative analysis. Accounting for this scattering, we present absolute scale quantitative comparisons between experiment and quantum mechanical calculations for both energy dispersive x-ray and electron energy-loss spectroscopy using off-axis reference measurements. The relative merits of removing the scattering effects from the experimental data against comparison with direct simulations are explored. © 2014 American Physical Society.