论文标题
SIC（0001）上的硝酸硼
Boron nitride on SiC(0001)
论文作者
论文摘要
在范德华异质结构的场中，已经确定堆叠的二维（2D）层之间的扭角对于异质结构的性质至关重要。在这种情况下，我们先前报道了在表面活性剂大气中形成的单一非常规外部石墨烯的单层生长[F. C. Bocquet等人，物理。莱特牧师。 125，106102（2020）]。所得的G-R0 $^\ Circ $ layer与SIC晶格一致，因此代表了朝着高质量扭曲双层石墨烯（TBLG）的重要里程碑，这是该领域经常研究的模型系统。在这里，我们专注于在同一表面活性剂大气中获得的表面结构，但在较低的制备温度下，氮化硼模板层在SIC（0001）上形成。在一项基于互补实验和理论技术的全面研究中，我们发现与文献相比，该模板层是六角形b $ _x $ n $ _y $ lays，但不是高质量的HBN。它与SIC晶格一致，并在退火时逐渐取代B $ _X $ n $ _y $ template层的0 $^\ circ $方向。
In the field of van der Waals heterostructures, the twist angle between stacked two-dimensional (2D) layers has been identified to be of utmost importance for the properties of the heterostructures. In this context, we previously reported the growth of a single layer of unconventionally oriented epitaxial graphene that forms in a surfactant atmosphere [F. C. Bocquet, et al., Phys. Rev. Lett. 125, 106102 (2020)]. The resulting G-R0$^\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.
