Neural RHEED alignment with limited training data during CdTe MBE growth

Bartłomiej Turowski; Jakub J. Meixner; Róża Dziewiątkowska; Wojciech Zaleszczyk; Tomasz Wojciechowski; Valentine V. Volobuev; Marcin M. Wysokiński; Tomasz Wojtowicz

arXiv · 2607.24467

Neural RHEED alignment with limited training data during CdTe MBE growth

Bartłomiej Turowski·Jakub J. Meixner·Róża Dziewiątkowska·Wojciech Zaleszczyk·Tomasz Wojciechowski·Valentine V. Volobuev·Marcin M. Wysokiński·Tomasz Wojtowicz

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Abstract

We introduce a data-efficient neural-vision assisted method to automate crystallographic alignment during molecular beam epitaxy (MBE) growth. Trained on reflection high-energy electron diffraction (RHEED) patterns from only 15 CdTe structures, our model - enabled by physics-aware postprocessing - reliably infers crystallographic directions, replacing manual frame-by-frame inspection. To this end, we design, test, and critically compare neural-network architectures based on 2D and 3D ResNet configurations, both with and without postprocessing that leverages the physical constraints of RHEED image acquisition. Our work delivers (i) a fully trained neural system ready for closed-loop deployment in future CdTe growth experiments and (ii) a generalizable pipeline for new materials where access to diverse RHEED datasets is limited. More broadly, this study represents a step toward AI-driven MBE growth and demonstrates the potential of machine-learning-assisted automation in thin-film synthesis.

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Bartłomiej Turowski, Jakub J. Meixner, Róża Dziewiątkowska, Wojciech Zaleszczyk, Tomasz Wojciechowski, Valentine V. Volobuev, Marcin M. Wysokiński, Tomasz Wojtowicz. 2026-07-27. Neural RHEED alignment with limited training data during CdTe MBE growth. https://arxiv.org/abs/2607.24467

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