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Probing the dielectric response of the interfacial buffer layer in epitaxial graphene via optical spectroscopy.

ABSTRACT: Monolayer epitaxial graphene (EG) is a suitable candidate for a variety of electronic applications. One advantage of EG growth on the Si face of SiC is that it develops as a single crystal, as does the layer below, referred to as the interfacial buffer layer (IBL), whose properties include an electronic band gap. Though much research has been conducted to learn about the electrical properties of the IBL, not nearly as much work has been reported on the optical properties of the IBL. In this work, we combine measurements from Mueller matrix ellipsometry, differential reflectance contrast, atomic force microscopy, and Raman spectroscopy, as well as calculations from Kramers-Kronig analyses and density functional theory (DFT), to determine the dielectric function of the IBL within the energy range of 1 eV to 8.5 eV.

SUBMITTER: Hill HM

PROVIDER: S-EPMC5846628 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Probing the dielectric response of the interfacial buffer layer in epitaxial graphene via optical spectroscopy.

Hill Heather M HM Rigosi Albert F AF Chowdhury Sugata S Yang Yanfei Y Nguyen Nhan V NV Tavazza Francesca F Elmquist Randolph E RE Newell David B DB Hight Walker Angela R AR

Physical review. B 20171128 19

Monolayer epitaxial graphene (EG) is a suitable candidate for a variety of electronic applications. One advantage of EG growth on the Si face of SiC is that it develops as a single crystal, as does the layer below, referred to as the interfacial buffer layer (IBL), whose properties include an electronic band gap. Though much research has been conducted to learn about the electrical properties of the IBL, not nearly as much work has been reported on the optical properties of the IBL. In this work ...[more]

PMID: 29541699

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