Transport mechanisms in a puckered graphene-on-lattice

T. Xu, A. Díaz Álvarez, W. Wei, D. Eschimese, S. Eliet, O. Lancry, E. Galopin, F. Vaurette, M. Berthe, D. Desremes, B. Wei, J. Xu, J. F. Lampin, E. Pallecchi, H. Happy, D. Vignaud and B. Grandidier

Nanoscale 10, 7519-7525 (2018)
Understanding the fundamental properties of graphene when its topography is patterned by the use of a compliant substrate is essential to improve the performances of graphene sensors. Here we suspend a graphene monolayer on SiO2 nanopillar arrays to form a puckered graphene-on-lattice and investigate the strain and electrical transport at the nanoscale. Despite a nonuniform strain in the graphene-on-lattice, the resistivity is governed by thermally activated transport and not the strain. We show that the high thermal activation energy results from a low charge carrier density and a periodic change of the chemical potential induced by the interaction of the graphene monolayer with the nanopillars, making the use of graphene-on-lattice attractive to further increase the electrical response of graphene sensors.