ABSTRACT
This chapter reviews the different attempts to obtain homogeneous large graphene flakes on silicon carbide (SiC). A special attention is given to quantum Hall effect (QHE), as not only it can serve as a convincing proof of the good quality of graphene layer, but also as the last experimental results demonstrate that graphene can seriously challenge semiconductor for the realization of resistance standards. In GaAs based quantum wells, in which the QHE has been also observed for decades now, the values of the quantum Hall resistances agree to within an uncertainty of only a few hundreds of billion from one device to another. In semiconductor-based heterostructures, like GaAs quantum wells, the transition between the two regimes is typically of the order of 4 K. Despite the remarkable observation of the half-integer QHE in graphene on SiC, the mobility remains modest. However, the mobility also decreases with increasing temperatures, a strong indication that beyond resonant scattering other mechanisms are at work.
