Wafer-Scale and Deterministic Patterned Growth of Monolayer MoS2 via Vapor-Liquid-Solid Method

TL;DR

This paper presents a vapor-liquid-solid (VLS) method for wafer-scale, deterministic growth of monolayer MoS2, achieving uniform, continuous, and patterned 2D TMDC layers with high reproducibility.

Contribution

The study introduces a VLS growth technique for MoS2 that enables wafer-scale uniformity, continuous films, and site-controlled patterning, advancing scalable 2D material synthesis.

Findings

4-inch-wafer-scale uniform MoS2 growth on SiO2/Si

2-inch-wafer-scale continuous MoS2 film on sapphire

Site-controlled patterning of MoS2 flakes and films

Abstract

Vapor transportation is the core process in growing transition-metal dichalcogenides (TMDCs) by chemical vapor deposition (CVD). One inevitable problem is the spatial inhomogeneity of the vapors. The non-stoichiometric supply of transition-metal precursors and chalcogen leads to poor control in products' location, morphology, crystallinity, uniformity and batch to batch reproducibility. While vapor-liquid-solid (VLS) growth involves molten precursors at the growth temperatures higher than their melting points. The liquid sodium molybdate can precipitate solid MoS2 monolayers when saturated with sulfur vapor. Taking advantage of the VLS growth, we achieved three kinds of important achievements: (a) 4-inch-wafer-scale uniform growth of MoS2 flakes on SiO2/Si substrates, (b) 2-inch-wafer-scale growth of continuous MoS2 film with a grain size exceeding 100 um on sapphire substrates, and (c) pattern (site-controlled) growth of MoS2 flakes and film. We clarified that the VLS growth thus pave the new way for the high-efficient, scalable synthesis of two-dimensional TMDC monolayers.