Introduction Graphene is a sp 2 bonded sheet of carbon atoms with honeycomb symmetry that shows non-dispersive transport characteristics. In graphene, electrons move as relativistic Dirac particles with a velocity ∼10× higher than in a conventional semiconductor. Carrier mobilities more than 100 000 cm 2 /V•s [1,2] and saturation velocities of about 5 × 10 7 cm −2 s −1 have been reported [3]. These properties in addition to a high current density up to 10 9 A/cm 2 and high thermal conductivity up to 5000 W m −1 K −1 [4] make it extremely appealing for applications in electronics. The two-dimensional nature of graphene enables tight control of the carrier density using the field effect [5], and permits the use of conventional semiconductor processing techniques. It is worth noting that most of these extraordinary properties are related to pristine graphene [6] under slightly idealized conditions such as graphene exfoliated from highly oriented pyrolitic graphite (HOPG), suspending the sheets between metal leads, or using an ultra flat and inert substrate as BN. In research and technology, graphene is used in more complex structures, and at conditions that are determined by the targeted applications. For instance, electrical transport is subject to a variety of scattering events [7-12]. The type of scattering mechanism that dominates in a specific sample could be derived from the magnitude of the carrier mobility (µ), and its dependence on temperature (T) and carrier density (n) [13]. Therefore, mobilities greater than 100 000 cm 2 /V•s are known to indicate scattering that is dominated by acoustic phonons, where µ AC ∼ 1/n [1,2,9]. This is typical for graphene when the substrate is removed and it is heated in order for the adsorbates to volatilize. Long-range Coulomb scattering results in mobilities of the order of 1000-10 000 cm 2 /V•s that are independent of carrier density, n [8,10,11]. It is related with charge impurities on graphene or more likely at the supporting insulator substrate. Neutral defects become significant in either highly defective samples or at high carrier densities and mobility dominated by short-range scatter, µ SR ∼ 1/n [7,11,14,15]. In most of the electronic applications graphene is supported by a dielectric substrate (typically SiO 2 or high-k dielectrics) or by semi-insulating SiC. In this cases the values of the electron mean free path l gr and mobility observed in Invited review Device applications of epitaxial graphene on silicon carbide M. Beshkova a, *

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Understanding the interaction between noble metals (NMs) and epitaxial graphene is essential for the design and fabrication of novel devices. Within this framework, a combined experimental and theoretical investigation of the effect of vapor‐deposited NM (silver [Ag] and gold [Au]) nanostructures on the vibrational and electronic properties of monolayer epitaxial graphene (MLG) on 4H‐SiC is presented. Large sets of Raman scattering data are analyzed using supervised classification and statistical methods. This analysis enables identification of the specific Raman fingerprints of Au‐ and Ag‐decorated MLG originating from different dispersion interactions and charge transfer at the metal nanostructure/MLG interface. It is found that Raman scattering spectra of Au‐decorated MLG feature a set of allowed phonon modes similar to those in pristine MLG, whereas the stronger Ag physisorption triggers an activation of defect‐related phonon modes and electron doping of MLG. A principal component analysis (PCA) and linear discriminant analysis (LDA) are leveraged to highlight the features in phonon dispersion of MLG that emanate from the NM deposition process and to robustly classify large‐scale Raman spectra of metal‐decorated graphene. The present results can be advantageous for designing highly selective sensor arrays on MLG patches decorated with different metals.