Resumo: Neste trabalho as propriedades morfológicas, estruturais, eletrônicas e ópticas dos materiais bidimensionais (2D) diseleneto de tungstênio (WSe2), disulfeto de tungstênio (WS2) e o nitreto de boro hexagonal (h-BN) foram investigadas por microscopia de força atômica, microscopia de varredura de tunelamento, espectroscopia Raman e fotoluminescência. As amostras de WSe2 foram preparadas a partir do bulk pelo método de exfoliação mecânica enquanto que as amostras de WS2 e h-BN foram preparadas a partir de flakes suspensos em solução usando os métodos de drop-casting e de spin-coating. Para observar a emissão de luz relacionada a defeitos pontuais, algumas amostras foram submetidas a tratamentos térmicos. Monocamadas de WSe2 sobre SiO2/Si 300 nm foram localizadas através de microscopia óptica. As monocamadas foram confirmadas por medidas de AFM, Raman e fotoluminescência....Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital Ver menos

Abstract: In this work the morphological, structural, electronic and optical properties of the twodimensional (2D) materials tungsten diselenide (WSe2), tungsten disulphide (WS2) and hexagonal boron nitride (h-BN) were investigated by atomic force microscopy, scanning tunneling microscopy, Raman and photoluminescence spectroscopy. The WSe2 samples were prepared from bulk material by the mechanical exfoliation method while the WS2 and h-BN samples were prepared from flakes in solution using drop-casting and spin-coating methods. In order to observe the light emission related to point defects, some samples were subjected to thermal annealing treatments. Monolayers of WSe2 on SiO2/Si 300 nm were located by optical microscopy. The monolayers were confirmed by AFM, Raman and photoluminescence measurements...Note: The complete abstract is available with the full electronic document Ver menos