Electrical Properties of GaAs Nanowires Grown on Graphene/SiC Hybrid Substrates

Resumo

The electrical properties of GaAs nanowires grown on a 6H-SiC (0001) substrate covered with graphene single layers and bilayers are studied. The nanowires are grown by molecular-beam epitaxy, with gold as a catalyst. The electrical properties are studied by measuring and analyzing the current–voltage characteristics of single nanowires vertically grown on a substrate. Numerical simulation of the experimental current–voltage curves revealed the presence of a ~0.6-V-high Schottky barrier between the nanowires and graphene. The appearance of the barrier is due to the formation of excess arsenic at the nanowire/graphene interface.