Neutralization of an epitaxial graphene grown on a SiC(0001) by means of palladium intercalation.

Pd-intercalated graphene grown on a SiC(0001) substrate was investigated using STM, angle- resolved photoemission spectroscopy, and XPS. Pd atoms deposited at room temperature on a zero layer graphene grown on a SiC(0001) substrate were intercalated between the zero layer graphene and the SiC substrate after the thermal annealing above 700 °C, forming a Pd-intercalated single layer graphene. No charge transfer occurred between the intercalated Pd layer and the graphene, which resulted in the formation of the electrically neutral graphene. The Pd-intercalated graphene remained electrically neutral throughout the annealing temperature range between 700 and 1100 °C. The charge transfer, however, occurred between the intercalated Pd layer and the SiC substrate, which caused a band bending confirmed in the core level spectra measured by XPS. [ABSTRACT FROM AUTHOR]