Immobilized Precursor Particle Driven Growth of Centimeter-Sized MoTe2 Monolayer

Molybdenum ditelluride (MoTe 2 ) has attracted ever-growing attention in recent years due to its novel characteristics in spintronics and phase-engineering, and an efficient and convenient method to achieve large-area high-quality film is an essential step toward electronic applications. However, the growth of large-area monolayer MoTe 2 is challenging. Here, for the first time, we achieve the growth of a centimeter-sized monoclinic MoTe 2 monolayer and manifest the mechanism of immobilized precursor particle driven growth. Microscopic characterizations reveal an obvious trend of immobilized precursor particles being consumed by the monolayer and continuing to provide a source for the growth of the monolayer. Time-of-flight secondary ion mass spectrometry verifies the attachment of hydroxide ions on the surface of the MoTe 2 monolayer, thereby realizing the inhibition of crystal growth along the [001] zone axis and the continuous growth of the MoTe 2 monolayer. The first-principles DFT calculations prove the mechanism of immobilized precursor particles and the absorption of hydroxide ions on the MoTe 2 monolayer. The as-grown MoTe 2 monolayer exhibits a surface roughness of 0.19 nm and average conductivity of 1.5 × 10 –5 S/m, which prove the smoothness and uniformity of the MoTe 2 monolayer. Temperature-dependent electrical measurements together with the transfer characteristic curves further demonstrate the typical semimetallic properties of monoclinic MoTe 2 . Our research elaborates the microscopic process of immobilized precursor particles to grow large-area MoTe 2 monolayer and provides a new thinking about the growth of many other two-dimensional materials.