Scalable Exfoliation of Large-Area TMD Monolayers and Highly Efficient Stacking of Their Heterostructures

Stacking transition metal dichalcogenide (TMDs) monolayers into van der Waals heterostructures enables interfacial charge transport and interface excitons, deepening our understanding of strong correlations and spin-valley coupling in low-dimensional materials. The exfoliation of large-scale TMD monolayers is crucial for constructing van der Waals heterostructures and for further exploring their unique properties. Extending the gold-assisted mechanical exfoliation method, we develop a polymer-assisted method combined with a novel hemispherical handle (HH) for the high-efficiency, large-area exfoliation, transfer, and stacking of MoS2, WS2, and other TMDs monolayers. The exfoliated monolayers exhibit lateral dimensions ranging from hundreds of micrometers to millimeters, maintaining clean interfaces and preserving structural integrity after transfer and stacking. This work presents an efficient, low-damage strategy for exfoliating and transferring large-area TMDs monolayers, facilitating their integration into optoelectronic devices and advancing related research.