Optimizing Experimental Conditions for Accurate Quantitative Energy-Dispersive X-ray Analysis of Interfaces at the Atomic Scale
Artikel i vetenskaplig tidskrift, 2021

The invention of silicon drift detectors has resulted in an unprecedented improvement in detection efficiency for energy-dispersive X-ray (EDX) spectroscopy in the scanning transmission electron microscope. The result is numerous beautiful atomic-scale maps, which provide insights into the internal structure of a variety of materials. However, the task still remains to understand exactly where the X-ray signal comes from and how accurately it can be quantified. Unfortunately, when crystals are aligned with a low-order zone axis parallel to the incident beam direction, as is necessary for atomic-resolution imaging, the electron beam channels. When the beam becomes localized in this way, the relationship between the concentration of a particular element and its spectroscopic X-ray signal is generally nonlinear. Here, we discuss the combined effect of both spatial integration and sample tilt for ameliorating the effects of channeling and improving the accuracy of EDX quantification. Both simulations and experimental results will be presented for a perovskite-based oxide interface. We examine how the scattering and spreading of the electron beam can lead to erroneous interpretation of interface compositions, and what approaches can be made to improve our understanding of the underlying atomic structure.

quantification

electron channeling

interfaces

EDX

Författare

Katherine E. MacArthur

Forschungszentrum Jülich

Andrew Yankovich

Chalmers, Fysik, Nano- och biofysik

Armand Béché

Universiteit Antwerpen

Martina Luysberg

Forschungszentrum Jülich

Hamish G. Brown

Lawrence Berkeley National Laboratory

Scott D. Findlay

Monash University

Marc Heggen

Forschungszentrum Jülich

Leslie J. Allen

University of Melbourne

Microscopy and Microanalysis

1431-9276 (ISSN) 1435-8115 (eISSN)

Vol. In Press

Ämneskategorier

Acceleratorfysik och instrumentering

Atom- och molekylfysik och optik

Annan fysik

DOI

10.1017/S1431927621000246

Mer information

Senast uppdaterat

2021-05-06