Fabricating Quasi-Free-Standing Graphene on a SiC(0001) Surface by Steerable Intercalation of Iron

Abstract

Graphene has been granted with appealing attributes for new-generation electronics due to its unique electronic properties. However, the interaction between graphene and the supporting substrate substantially limits its technological application. Here, we demonstrate the transformation of epitaxial monolayer graphene on SiC(0001) into decoupled bilayer graphene using steerable iron intercalation manipulated by thermal annealing. By means of Raman scattering and photoemission measurements, we have performed an in-depth investigation of the intercalation procedure and shown the quasifree-standing nature of the decoupled bilayer graphene afterward, as characterized by its unique structural and electronic properties. The intercalation of Fe atoms can be manipulated through temperature-driven processes after adsorption on top of the graphene layer, and this substantially modifies the interfacial interaction between the buffer layer and SiC substrate and, correspondingly, the doping level of the pristine graphene, ultimately resulting in the decoupling of buffer layer from the substrate. Although the decoupling of epitaxial graphene grown on silicon carbide has previously been a critical issue, our study highlights a feasible approach for producing high-quality quasi-free-standing graphene on SiC in a well-controlled manner, and for tuning the intrinsic electronic properties of lateral graphene/SiC lateral structure by ferromagnetic element intercalation.

Raman study of the substrate influence on graphene synthesis using a solid carbon source via rapid thermal annealing

“…These properties mean that graphene could be used in many technological fields including transparent electrodes, field emitters, biosensors, and batteries, to cite but a few examples. Many techniques exist for producing graphene including chemical vapor deposition, chemical reduction of graphene oxide, exfoliation, epitaxial growth on SiC or metal substrates, and physical vapor deposition methods including pulsed laser deposition (PLD) . Whatever the synthesis route chosen, many experimental factors affect the graphene nanoarchitecture and properties.…”

Energetics of Cu adsorption and intercalation at graphite step edges

“…The 2D materials also offer the opportunity to tune properties via intercalation, and such opportunity has been, and continues to be, heavily explored [2,3,4,5,6,7]. Intercalation can also be used as a means to promote exfoliation of layered materials or to decouple an as-grown layer from the substrate, hence facilitating production of 2D materials [8,9,10,11,12,13,14]. The most heavily-investigated system in this regard is supported graphene [6,5,4,2].…”

Long-range ordered and atomic-scale control of graphene hybridization by photocycloaddition

“…using an inVia Raman spectrometer (Renishaw, U.K.) with incident wavelength of 532 nm. Angle resolved photoemission spectroscopy (ARPES) measurements 39 were carried out at the Dreamline (BL09U) in Shanghai Synchrotron Radiation Facility using a VG-Scienta DA30 electron analyser with a base pressure of 5 × 10 -11 mbar and the sample kept at 5 K. The photon energy was set at 70 eV and calibrated by measuring the Fermi level of the metal sample plate. The angular resolution was 0.2°; the energy resolution was 5 meV.…”