Molecular Beam Epitaxy of Highly Crystalline MoSe2 on Hexagonal Boron Nitride
journal contributionposted on 2018-07-09, 17:54 authored by Sock Mui Poh, Xiaoxu Zhao, Sherman Jun Rong Tan, Deyi Fu, Wenwen Fei, Leiqiang Chu, Dan Jiadong, Wu Zhou, Stephen J. Pennycook, Antonio H. Castro Neto, Kian Ping Loh
Molybdenum diselenide (MoSe2) is a promising two-dimensional material for next-generation electronics and optoelectronics. However, its application has been hindered by a lack of large-scale synthesis. Although chemical vapor deposition (CVD) using laboratory furnaces has been applied to grow two-dimensional (2D) MoSe2 cystals, no continuous film over macroscopically large area has been produced due to the lack of uniform control in these systems. Here, we investigate the molecular beam epitaxy (MBE) of 2D MoSe2 on hexagonal boron nitride (hBN) substrate, where highly crystalline MoSe2 film can be grown with electron mobility ∼15 cm2/(V s). Scanning transmission electron microscopy (STEM) shows that MoSe2 grains grown at an optimum temperature of 500 °C are highly oriented and coalesced to form continuous film with predominantly mirror twin boundaries. Our work suggests that van der Waals epitaxy of 2D materials is tolerant of lattice mismatch but is facilitated by substrates with similar symmetry.
Hexagonal Boron Nitride Molybdenum diselenideMolecular Beam EpitaxyCrystalline MoSe 2van der Waals epitaxylaboratory furnacesMoSe 2 grainsboron nitrideMoSe 2next-generation electronicsbeam epitaxyMoSe 2 cystalslattice mismatchuniform controlScanning transmission electron microscopyCVDMBEchemical vapor depositionMoSe 2 film2 D materials