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arXiv · 1906.01471

Depth, relaxation and temperature dependence of defect complexes in scanning transmission electron microscopy

Thomas Aarholt·Ymir Frodason·Øystein Prytz
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Abstract

We propose a new analysis approach for scanning transmission electron microscopy (STEM) based on the Voronoi-cell integration method to determine the three-dimensional position of the InZn and VZn defect complex in ZnO. Using state of the art simulation software and hardware, we propose using a method of calculating Michelson Contrast on simulated images to determine the optimal acceptance angles to use in an experimental setting. The effect of defect position, DFT-relaxation and cooling the sample to liquid nitrogen temperatures is investigated. DFT-relaxation is shown to be of consequence to accurately determine the three-dimensional position of the defect. Relaxation is also shown to have a significant impact on neighbouring columns at liquid nitrogen temperatures.

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Thomas Aarholt, Ymir Frodason, Øystein Prytz. 2019-06-04. Depth, relaxation and temperature dependence of defect complexes in scanning transmission electron microscopy. https://arxiv.org/abs/1906.01471

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