Thesis Type: Postgraduate
Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2012
Student: KENAN ELİBOL
Supervisor: SEFER BORA LİŞESİVDİN
Abstract:In this study, the properties of the surface and magnetoconductivity of exfoliated and epitaxially grown graphene samples were investigated. The properties of the surface of graphene samples were investigated by using optical microscope, AFM, and SEM. The Raman spectrum was measured to determine the number of layers which the epitaxial graphene samples have. The graphene devices were fabricated by using optical and e-beam lithography methods for Hall effect and I-V measurements. I-V characteristics of the exfoliated and epitaxially grown graphene samples were measured. To investigate the effect of light on the properties of magnetoconductivity of graphene, under of a fixed magnetic field, Hall effect measurements were carried out under dark and then illumination conditions at the 25-300 K temperature range. To investigate the effects of helium gas and water on Hall measurements of epitaxial graphene, under of a fixed magnetic field, Hall effect measurements were carried out at the 30-300 K temperature range. To better understand the interaction of helium with graphene, DFT calculations were performed.