Figure 4: MR of Au|graphene|Au stacks with minimum PMMA residue after annealing.
From: Layer-by-layer assembly of vertically conducting graphene devices
(a) The MR of an Au|monolayer graphene|Au device (sample AT1). The top electrode was fabricated via transferring a gold strip after the PMMA residues on graphene were reduced by annealing. (b) The resistance difference between 1.8 and 300 K (R(1.8 K)−R(300 K)) of sample AT1 shows the deviation from linear magnetic field dependence and the appearance of oscillations at high magnetic field. (c) The SdH oscillations of sample AT1 under 14 T as a function of carrier concentration tuned by back gate voltage. Inset: the filling factor of the SdH oscillations as a function of the valley position in gate voltage. (d) The MR of an Au|two-layer graphene|Au device without any PMMA residues between the graphene layers (sample AT2).
