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

Two-dimensional (2D) van der Waals (vdW) heterostructures have emerged as a groundbreaking candidate for future integrated circuits due to their tunable band structures, atomically sharp interfaces and seamless compatibility with complementary metal-oxide-semiconductor 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 unveils for the first time the direct epitaxial growth of wafer-scale 2D vdW heterostructures (MoS[Formula: see text]/SnS[Formula: see text]) 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 MoS[Formula: see text] and SnS[Formula: see text] are constrained to below 0.5 cm[Formula: see text] 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 [Formula: see text] 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.