Estudo de propriedades morfológicas, eletrônicas e de magneto transporte em grafeno depositado sobre talco, nitreto de boro e dióxido de silício

• Ano de defesa: 2015
• Autor(a) principal: Edrian Mania
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais
• Palavras-chave em Português: dióxido de silício; mobilidade eletrônica; histerese; Talco; magneto transporte; Física; Grafeno; Histerese; Magneto transporte; Nitreto de boro hexagonal; Mobilidade eletrônica
• Link de acesso: https://hdl.handle.net/1843/BUBD-AA8FF6

Graphene is a two dimensional material composed by carbon atoms arranged in a honeycomb lattice. During the past decade, it has attracted enormous interest due to the relativistic Dirac nature of its charge carriers and its potential for industrial application. For instance, charge carriers in graphene can move for distances over a micrometer without being scattered, and the electronic properties of graphenes with more than one layer are electronically tunable. However, achieve the intrinsic physical properties of graphene is challenging. Charge scattering and surface imperfection at non-flat substrates strongly affect electronic transport of graphene obscuring its intrinsic properties. In this work we investigate electronic properties of graphene devices on silicon substrates and on top of flat substrates like hexagonal boron nitride and talc. Hexagonal boron nitride shows the cleanest charge environment for graphene devices while devices on talc show instability and charge hysteresis which are still not understood. We show analyses based on optical microscopy, atomic force microscope, electronic measurement and magneto transport of graphene devices on these three substrates.