EPITAXIAL GRAPHENE How silicon leaves the scene

Large and homogeneous layers of graphene are obtained by annealing silicon carbide in a dense noble gas atmosphere that controls the way in which silicon sublimates. Emtsev and co-workers have demonstrated an important step towards this goal for a specific fabrication strategy, graphene epitaxy on silicon carbide (SiC). They began by comparing the electron mobility, a measure of the charge carrier drift velocity in an applied electric field for samples prepared in vacuum and in ambient-pressure argon, patterned into simple test structures. Samples produced by the new process show a nearly twofold improvement over the previous record mobility in Si-face epitaxial graphene. This study prepares for their identification for epitaxial graphene on SiC by reducing roughness and increasing the graphene domain size. The improved properties demonstrated by Emtsev and coworkers provides an additional performance measurement for this technology.