The growth of inch-scale high-quality graphene on insulating substrates is desirable for electronic and optoelectronic applications, but remains challenging due to the lack of metal catalysis. Here we demonstrate the wafer-scale synthesis of adlayer-free ultra-flat single-crystal monolayer graphene on sapphire substrates. We converted polycrystalline Cu foil placed on Al2O3(0001) into single-crystal Cu(111) film via annealing, and then achieved epitaxial growth of graphene at the interface between Cu(111) and Al2O3(0001) by multi-cycle plasma etching-assisted–chemical vapour deposition. Immersion in liquid nitrogen followed by rapid heating causes the Cu(111) film to bulge and peel off easily, while the graphene film remains on the sapphire substrate without degradation. Field-effect transistors fabricated on as-grown graphene exhibited good electronic transport properties with high carrier mobilities. This work breaks a bottleneck of synthesizing wafer-scale single-crystal monolayer graphene on insulating substrates and could contribute to next-generation graphene-based nanodevices.
KAUST Repository Item: Exported on 2022-01-25
Acknowledged KAUST grant number(s): OSR-2016-CRG5-2996, OSR-2018-CRG7-3717
Acknowledgements: We thank A. Chen for providing suggestions on device fabrication. We thank F. Laquai and Y. Gao for help with UV–vis spectrum measurements, and N. Wehbe for help with D-SIMS measurements. We thank D. Luo and M. Wang for comments. X.Z. acknowledges the support from KAUST, under award numbers OSR-2018-CRG7-3717 and OSR-2016-CRG5-2996, and R.S.R. acknowledges the support from IBS-R-019-D.
- Mechanics of Materials
- Materials Science(all)
- Mechanical Engineering
- Condensed Matter Physics