Direct Growth of Graphene by Molecular Beam Epitaxy for the Formation of Graphene Heterostructures

Abstract

Growth of single- and few-layer macroscopically continuous graphene films on Co3O4(111) by molecular beam epitaxy (MBE) has been characterized using low energy electron diffraction (LEED), Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS). MBE of Co on sapphire(0001) at 750 K followed by annealing in UHV (1000 K) results in ˜3 monolayers (ML) of Co3O4(111) due to O segregation from the bulk. Subsequent MBE of C at 1000 K from a graphite source yields a graphene LEED pattern incommensurate with that of the oxide, indicating graphene electronically decoupled from the oxide, as well as a sp2 C(KVV) Auger lineshape, and π→π* C(1s) XPS satellite. The data strongly suggest the ability to grow graphene on other structurally similar magnetic/magnetoelecric oxides, such as Cr2O3(111)/Si for spintronic applications.

Dependencies are inferred from the claim text.