Direct orientational-epitaxy of wafer-scale 2D van der Waals heterostructures of metal dichalcogenides

Abstract 2D van der Waals (vdW) heterostructures emerges as a groundbreaking candidate for future integrated circuits due to their tunable band structures, atomically sharp interfaces, and seamless compatibility with CMOS technologies. Despite their promise, existing synthesis methods, such as mechanical transfer and vapor-phase conversion, struggle to achieve the high-quality, scalable production for practical applications. In response to these longstanding challenges, our study for the first time unveils the direct epitaxial growth of wafer-scale 2D vdW heterostructures (MoS2/SnS2) with exceptional quality and uniformity. This achievement is made possible through fundamentally enhancing the adsorption interactions between intermediates and the underlying material. The heterostructures display pristine, defect-free interfaces, consistent crystal orientation, and wafer-level thickness uniformity. The Raman peak shifts of MoS2 and SnS2 are contained to below 0.5 cm−1 across the entire wafer, with intensity deviations maintained within an impressive 2%, and thickness uniformity surpassing 99.5%. Owing to their exceptional crystallinity and interface quality, the heterostructures demonstrate extraordinary electron and hole transfer capabilities, showcasing a prominent rectification effect and an astounding responsivity of 6.28× 103 A/W, averaged from 30 devices. Our study signifies a pivotal advancement for the integration of 2D materials into semiconductor technologies, paving the way for next-generation integrated circuits.