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DOE OSTI · 2568370

Revealing Variable Dependences in Hexagonal Boron Nitride Synthesis via Machine Learning

Abstract

Wafer-scale monolayer two-dimensional (2D) materials have been realized by epitaxial chemical vapor deposition (CVD) in recent years. To scale up the synthesis of 2D materials, a systematic analysis of how the growth dynamics depend on the growth parameters is essential to unravel its mechanisms. However, the studies of CVD-grown 2D materials mostly adopted the control variate method and considered each parameter as an independent variable, which is not comprehensive for 2D materials growth optimization. Herein, we synthesized a representative 2D material, monolayer hexagonal boron nitride (hBN), on single-crystalline Cu (111) by epitaxial chemical vapor deposition and varied the growth parameters to regulate the hBN domain sizes. Furthermore, we explored the correlation between two growth parameters and provided the growth windows for large flake sizes by the Gaussian process. Here, this new analysis approach based on machine learning provides a more comprehensive understanding of the growth mechanism for 2D materials.

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BibTeXRIS

Park, Ji-Hoon, Lu, Ang-Yu, Tavakoli, Mohammad Mahdi, Kim, Na Yeon, Chiu, Ming-Hui, Liu, Hongwei, Zhang, Tianyi, Wang, Zhien, Wang, Jiangtao, Martins, Luiz Gustavo Pimenta, Luo, Zhengtang, Chi, Miaofang, Miao, Jianwei, Kong, Jing. 2023-05-17. Revealing Variable Dependences in Hexagonal Boron Nitride Synthesis via Machine Learning. https://doi.org/10.1021/acs.nanolett.2c04624

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36 MATERIALS SCIENCE↗