The integration of wafer-scale two-dimensional (2D) materials, such as graphene, onto device wafers remains a significant challenge for practical applications due to persistent issues of transfer-induced defects, including polymer-residue contamination and film cracks. Here, we demonstrate a van der Waals assembly technique that achieves a damage-free transfer of graphene by simultaneously modulating interfacial hydrophobicity and electrostatic charge distribution. This approach eliminates the need for polymer carriers, thereby preserving the intrinsic properties of graphene. The electrostatic conformal adhesion between copper-grown graphene and the target substrates ensures surface cleanliness and structural integrity. The intercalation of the etchant solution at the graphene-substrate interface is effectively prevented by the hydrophobic interface, which ensures direct interfacial contact and maintains the structural integrity. The transferred graphene films exhibited 99.7 ± 0.3% coverage, subnanometer root-mean-square roughness of 0.697 nm, and room-temperature field-effect mobility up to 6651 cm2·V–1·s–1. This technique is applicable to various substrates, including SiO2/Si, polyethylene terephthalate (PET), polyvinyl chloride (PVC), quartz, and sapphire, and is compatible with standard semiconductor manufacturing processes. Consequently, this transfer approach provides a scalable pathway for the fabrication of graphene-based devices.
Zhang et al. (Thu,) studied this question.