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arXiv · 1903.09101

Scanning Probe State Recognition With Multi-Class Neural Network Ensembles

Abstract

One of the largest obstacles facing scanning probe microscopy is the constant need to correct flaws in the scanning probe in situ. This is currently a manual, time-consuming process that would benefit greatly from automation. Here we introduce a convolutional neural network protocol that enables automated recognition of a variety of desirable and undesirable scanning probe tip states on both metal and non-metal surfaces. By combining the best performing models into majority voting ensembles, we find that the desirable states of H:Si(100) can be distinguished with a mean precision of 0.89 and an average receiver-operator-characteristic curve area of 0.95. More generally, high and low-quality tips can be distinguished with a mean precision of 0.96 and near perfect area-under-curve of 0.98. With trivial modifications, we also successfully automatically identify undesirable, non-surface-specific states on surfaces of Au(111) and Cu(111). In these cases we find mean precisions of 0.95 and 0.75 and area-under-curves of 0.98 and 0.94, respectively.

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O. Gordon, P. D'Hondt, L. Knijff, S. Freeney, F. Junqueira, P. Moriarty, I. Swart. 2019-03-21. Scanning Probe State Recognition With Multi-Class Neural Network Ensembles. https://doi.org/10.1063/1.5099590

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