Hyun Je Cho1,2,Jong Yun Choi1,2,Heonsu Ahn1,2,Geonho Mun1,2,Jaeyoung Kim2,Hyunjin Jung2,Moon-Ho Jo1,2
POSTECH1,Institute for Basic Science2
Hyun Je Cho1,2,Jong Yun Choi1,2,Heonsu Ahn1,2,Geonho Mun1,2,Jaeyoung Kim2,Hyunjin Jung2,Moon-Ho Jo1,2
POSTECH1,Institute for Basic Science2
We report single crystalline monolayer tungsten disulfide (WS<sub>2</sub>) growth on high miscut angle c-plane sapphire substrate. Unlike other step-edge-guided growth, we use high miscut angle substrate to initiate uni-directional nucleation. Since the high miscut angle substrate containing high portion of step-edge, terrace nucleation had succesively suppressed, leading to high quality single crystalline monolayer film can be acquired. Single crystalline texture is verified by microscopies and transmission electron microscope studies. Moreover, low energy electron diffraction measurements at different points perfectly exhibit 3-fold symmetry without any angle deviation. We also synthesize monolayer WS<sub>2</sub> nanoribbon by controlling the anisotropic growth. Finally, we show electronic and optoelectronic properties of our single crystal WS<sub>2</sub> film and WS<sub>2</sub> nanoribbon. Our method not only offers a universal and scalable growth strategy to produce TMDC single crystals for future electronics, but also gives perfect platform for studying large scale moiré physics.<br/><br/>References<br/>1. L. Wang et al. Epitaxial growth of a 100-square-centimetre single-crystal hexagonal boron nitride monolayer on copper. Nature 570, 91 (2019)<br/>2. K. V. Bets et al. How the complementarity at vicinal steps enables growth of 2D monocrystals. Nano Lett. 19, 2027–2031 (2019).