High-Mobility, Wet-Transferred Graphene Grown by Chemical Vapor Deposition

We report high room-temperature mobility in single-layer graphene grown by chemical vapor deposition (CVD) after wet transfer on SiO2 and hexagonal boron nitride (hBN) encapsulation. By removing contaminations, trapped at the interfaces between single-crystal graphene and hBN, we achieve mobilities up to ∼70000 cm^2 V^–1 s^–1 at room temperature and ∼120 000 cm^2 V^–1 s^–1 at 9K. These are more than twice those of previous wet-transferred graphene and comparable to samples prepared by dry transfer. We also investigate the combined approach of thermal annealing and encapsulation in polycrystalline graphene, achieving room-temperature mobilities of ∼30 000 cm^2 V^–1 s^–1. These results show that, with appropriate encapsulation and cleaning, room-temperature mobilities well above 10 000 cm^2 V^–1 s^–1 can be obtained in samples grown by CVD and transferred using a conventional, easily scalable PMMA-based wet approach.