TY  - JOUR
AU  - Fatermans, J.
AU  - den Dekker, A. J.
AU  - Müller-Caspary, K.
AU  - Gauquelin, N.
AU  - Verbeeck, J.
AU  - Van Aert, S.
TI  - Atom column detection from simultaneously acquired ABF and ADF STEM images
JO  - Ultramicroscopy
VL  - 219
SN  - 0304-3991
CY  - Amsterdam
PB  - Elsevier Science
M1  - FZJ-2021-02905
SP  - 113046 -
PY  - 2020
AB  - In electron microscopy, the maximum a posteriori (MAP) probability rule has been introduced as a tool to determine the most probable atomic structure from high-resolution annular dark-field (ADF) scanning transmission electron microscopy (STEM) images exhibiting low contrast-to-noise ratio (CNR). Besides ADF imaging, STEM can also be applied in the annular bright-field (ABF) regime. The ABF STEM mode allows to directly visualize light-element atomic columns in the presence of heavy columns. Typically, light-element nanomaterials are sensitive to the electron beam, limiting the incoming electron dose in order to avoid beam damage and leading to images exhibiting low CNR. Therefore, it is of interest to apply the MAP probability rule not only to ADF STEM images, but to ABF STEM images as well. In this work, the methodology of the MAP rule, which combines statistical parameter estimation theory and model-order selection, is extended to be applied to simultaneously acquired ABF and ADF STEM images. For this, an extension of the commonly used parametric models in STEM is proposed. Hereby, the effect of specimen tilt has been taken into account, since small tilts from the crystal zone axis affect, especially, ABF STEM intensities. Using simulations as well as experimental data, it is shown that the proposed methodology can be successfully used to detect light elements in the presence of heavy elements.
LB  - PUB:(DE-HGF)16
C6  - 32927326
UR  - <Go to ISI:>//WOS:000594768500005
DO  - DOI:10.1016/j.ultramic.2020.113046
UR  - https://juser.fz-juelich.de/record/893893
ER  -