Quantitative atomic resolution elemental mapping via absolute-scale energy dispersive X-ray spectroscopy.
Quantitative agreement on an absolute scale is demonstrated between experiment and simulation for two-dimensional, atomic-resolution elemental mapping via energy dispersive X-ray spectroscopy. This requires all experimental parameters to be carefully characterized. The agreement is good, but some discrepancies remain. The most likely contributing factors are identified and discussed. Previous predictions that increasing the probe forming aperture helps to suppress the channelling enhancement in the average signal are confirmed experimentally. It is emphasized that simple column-by-column analysis requires a choice of sample thickness that compromises between being thick enough to yield a good signal-to-noise ratio while being thin enough that the overwhelming majority of the EDX signal derives from the column on which the probe is placed, despite strong electron scattering effects.
School of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia.
Z
Z
Chen
Monash Centre for Electron Microscopy, Monash University, Clayton, Victoria 3800, Australia; Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia.
M
M
Weyland
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695, USA.
X
X
Sang
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695, USA.
W
W
Xu
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695, USA.
J H
JH
Dycus
Department of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695, USA.
J M
JM
LeBeau
School of Physics, University of Melbourne, Parkville, Victoria 3010, Australia.
A J
AJ
D'Alfonso
School of Physics, University of Melbourne, Parkville, Victoria 3010, Australia.
L J
LJ
Allen
School of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia. Electronic address: scott.findlay@monash.edu.
S D
SD
Findlay
Atomic-resolution mapping; Elemental quantification; Energy dispersive X-ray (EDX) spectroscopy; Scanning transmission electron microscopy (STEM)