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arXiv · 2409.07663

Sensitivity of Multislice Electron Ptychography to Point Defects: A Case Study in SiC

Aaditya Bhat·Colin Gilgenbach·Junghwa Kim·Michael Xu·Menglin Zhu·James M. LeBeau
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Abstract

Here, we evaluate multislice electron ptychography as a tool to carry out depth-resolved atomic resolution characterization of point defects, using silicon carbide as a case study. Through multislice electron scattering simulations and multislice ptychographic reconstructions, we investigate the phase contrast arising from individual silicon vacancies, antisite defects, and a wide range of substitutional transition metal dopants (V\textsubscript{Si} to W\textsubscript{Si}) and potential detectability. Simulating defect types, positions, and microscope conditions, we show that isolated point defects can be located within a unit cell along the sample's depth. The influence of electron energy, dose, defocus, and convergence semi-angle is also explored to determine their role in governing defect contrast. These results guide experiments aiming to analyze point defects with multislice electron ptychography.

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Aaditya Bhat, Colin Gilgenbach, Junghwa Kim, Michael Xu, Menglin Zhu, James M. LeBeau. 2024-09-11. Sensitivity of Multislice Electron Ptychography to Point Defects: A Case Study in SiC. https://arxiv.org/abs/2409.07663

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