Morphology Control of Epitaxial Monolayer Transition Metal Dichalcogenides

Abstract

To advance fundamental understanding, and ultimate application, of transition-metal dichalcogenide (TMD) monolayers, it is essential to develop capabilities for the synthesis of high-quality single-layer samples. Molecular beam epitaxy (MBE), a leading technique for the fabrication of the highest-quality epitaxial films of conventional semiconductors has, however, typically yielded only small grain sizes and sub-optimal morphologies when applied to the van der Waals growth of monolayer TMDs. Here, we present a systematic study on the influence of adatom mobility, growth rate, and metal:chalcogen flux on the growth of NbSe2, VSe2 and TiSe2 using MBE. Through this, we identify the key drivers and influence of the adatom kinetics that control the epitaxial growth of TMDs, realising four distinct morphologies of the as-grown compounds. We use this to determine optimised growth conditions for the fabrication of high-quality monolayers, ultimately realising the largest grain sizes of monolayer TMDs that have been achieved to date via MBE growth.

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• Unique gap structure and symmetry of the charge density wave in single-layer VSe${}_2$
• Spin-valley locking in the normal state of a transition-metal dichalocogenide superconductor
• Absence of ferromagnetism in VSe${}_2$ caused by its charge density wave phase
• Orbital- and $k_z$-selective hybridisation of Se 4p and Ti 3d states in the charge density wave phase of TiSe${}_2$
• Experimental and Theoretical Electronic Structure and Symmetry Effects in Ultrathin NbSe2 Films

Cited by in corpus (13)

• Machine-learning-assisted analysis of transition metal dichalcogenide thin-film growth
• Refractive uses of layered and two-dimensional materials for integrated photonics
• Orbital-selective Band Hybridisation at the Charge Density Wave Transition in Monolayer TiTe${}_2$
• Metastable polymorphic phases in monolayer TaTe2
• Molecular Beam Epitaxy of a 2D material nearly lattice matched to a 3D substrate: $NiT{e}_2$ on $GaAs$
• Charge-Density Waves vs. Superconductivity: Some Results and Future Perspectives
• From ferromagnetic semiconductor to anti-ferromagnetic metal in epitaxial Cr${}_x$Te${}_y$ monolayers
• Persistence of charge ordering instability to Coulomb engineering in the excitonic insulator candidate TiSe${}_2$
• Reversal of charge transfer doping on the negative electronic compressibility surface of MoS2
• Harnessing ultrafast optical pulses for 3D microfabrication by selective tweezing and immobilization of colloidal particles in an integrated system
• Effect of manganese incorporation on the excitonic recombination dynamics in monolayer MoS${}_2$
• Substrate pre-sputtering for layer-by-layer van der Waals epitaxy of 2D materials
• Resonant interlayer coupling in NbSe${}_2$-graphite epitaxial moir{é} superlattices