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arXiv · 2203.00985

Boron nitride on SiC(0001)

You-Ron Lin·Markus Franke·Shayan Parhizkar·Miriam Raths·Victor Wen-zhe Yu·Tien-Lin Lee·Serguei Soubatch·Volker Blum·F. Stefan Tautz·Christian Kumpf·François C. Bocquet
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Abstract

In the field of van der Waals heterostructures, the twist angle between stacked two-dimensional (2D) layers has been identified to be of utmost importance for the properties of the heterostructures. In this context, we previously reported the growth of a single layer of unconventionally oriented epitaxial graphene that forms in a surfactant atmosphere [F. C. Bocquet, et al., Phys. Rev. Lett. 125, 106102 (2020)]. The resulting G-R0$^\circ$ layer is aligned with the SiC lattice, and hence represents an important milestone towards high quality twisted bilayer graphene (tBLG), a frequently investigated model system in this field. Here, we focus on the surface structures obtained in the same surfactant atmosphere, but at lower preparation temperatures at which a boron nitride template layer forms on SiC(0001). In a comprehensive study based on complementary experimental and theoretical techniques, we find -- in contrast to the literature -- that this template layer is a hexagonal B$_x$N$_y$ layer, but not high-quality hBN. It is aligned with the SiC lattice and gradually replaced by low-quality graphene in the 0$^\circ$ orientation of the B$_x$N$_y$ template layer upon annealing.

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You-Ron Lin, Markus Franke, Shayan Parhizkar, Miriam Raths, Victor Wen-zhe Yu, Tien-Lin Lee, Serguei Soubatch, Volker Blum, F. Stefan Tautz, Christian Kumpf, François C. Bocquet. 2022-03-02. Boron nitride on SiC(0001). https://doi.org/10.1103/physrevmaterials.6.064002

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