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 similar to 70000 cm(2) V-1 s(-1) at room temperature and similar to 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 similar to 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.