Influence of the growth conditions of epitaxial graphene on the film topography and the electron transport properties

In this work we report on temperature-dependent magnetotransport measurements on epitaxial graphene grown on SiC(0001)(0001) under different preparation conditions. We demonstrate that the temperature dependence of the charge carrier density and mobility is correlated to the annealing conditions during the graphitization process. As recently shown, SiC substrates annealed in an Ar atmosphere near atmospheric pressure exhibit continuous monolayer graphene films over 2–3μm wide and more than 50μm long terraces. For these films we determine a constant charge carrier density in the range from 1.4 K up to room temperature and an electron mobility exceeding 3000cm2(Vs)-1 at low temperatures.