Tailored Vapor Deposition Unlocks Large-Grain, Wafer-Scale Epitaxial Growth of 2D Magnetic CrCl3

TL;DR

This paper presents a scalable vapor deposition method for large-area, high-quality 2D magnetic CrCl3 films, enabling wafer-scale growth with controlled thickness and transfer capabilities.

Contribution

Developed a tailored physical vapor transport deposition process for wafer-scale growth of 2D magnetic CrCl3 with precise control over film quality and thickness.

Findings

Achieved centimeter-scale, phase-pure CrCl3 films on mica.

Demonstrated control over film thickness from few-layers to tens of nanometers.

Enabled selective-area growth and large-area transfer of 2D CrCl3.

Abstract

Two-dimensional magnetic materials (2D-MM) are an exciting playground for fundamental research, and for spintronics and quantum sensing. However, their large-grain large-area synthesis using scalable vapour deposition methods is still an unsolved challenge. Here, we develop a tailored approach for centimetre-scale growth of semiconducting 2D-MM CrCl3 films on mica substrate, via physical vapour transport deposition. A controlled synthesis protocol, enabled via innovations concerning light management, very-high carrier-gas flow, precursor flux, and oxygen/moisture removal, is critical for wafer-scale growth. Optical, stoichiometric, structural, and magnetic characterization identify crystalline, phase-pure 2D-MM CrCl3. Substrate temperature tunes thickness of films from few-layers to tens of nanometres. Further, selective-area growth and large-area transfer are demonstrated. Substrate-dependent growth features are explained by density functional theory and state-of-the-art machine learning interatomic potential-based atomic-scale simulations. This scalable vapour deposition approach can be applied for growth of several 2D-MM, and low growth temperature (~500 C) will enable creation of hybrid heterostructures.