▎ 摘 要
When epitaxial graphene layers are formed on SiC(0001), the first carbon layer (known as the "buffer layer"), while relatively easy to synthesize, does not have the desirable electrical properties of graphene. The conductivity is poor due to a disruption of the graphene pi bands by covalent bonding to the SiC substrate. Here we show that it is possible to restore the graphene pi bands by inserting a thin oxide layer between the buffer layer and SiC substrate using a low temperature, complementary metal-oxide semiconductor-compatible process that does not damage the graphene layer.