Investigation of swift heavy ion irradiated graphitic surfaces and novel graphene based devices

Tailoring materials with atomic scale defects have been studied over decades. In recent years, It had been understood that making a functional electronic device with extremely small size (several tens of nanometers) by use of novel materials such as graphene requires introducing defects. One way of achieving this goal is swift heavy ion (SHI) irradiation. In the first part of the study, we investigated defect formation on swift heavy ion (uranium and lead) irradiated graphitic surfaces by means of Scanning Tunneling Microscopy with a focus on HOPG and dislocated graphene layers on HOPG (moiré zones). Our results showed that structures that form on HOPG surfaces due to SHI irradiation in perpendicular geometry have a variety of shapes and sizes rather than just being hillock like. Moreover, comet-like structures were observed on HOPG surfaces due to SHI irradiation under 80o incidence angle with respect to surface normal. Obtaining atomic resolution on the tail section of the comet-like structures proved that SHI does not damage the surface layers while it is traversing in the bulk of the crystal. On the other hand SHI Irradiation of moiré zones under 80o incidence angle and SHI irradiation of moiré zones under grazing incidence (87.5o) did neither show destruction of the graphene layer generating the moiré pattern, nor any unzipping of the graphene as shown to happen on SHI irradiation of graphene crystals on dielectric substrates. Rather, the defects forming as a result of these lead and uranium irradiations were comet-like both on pristine HOPG samples as well as on moiré domains. Furthermore, irradiation of moiré zones with perpendicular geometry has been studied. It was observed that moiré zones may remain unharmed or they may locally destroyed upon SHI irradiation due to electronic changes in the bulk or moiré zone itself. We also studied tribological properties of SHI irradiated HOPG surfaces by means of Friction Force Microscopy (FFM). Our FFM measurements showed complementary results to our STM measurements. We observed that the head sections of the comet like structures appeared on simultaneously measured topography and friction maps. Intriguingly, tail sections of the comet-like structures appeared on friction maps, although they could not have been observed on topography maps. In some cases tails sections showed less friction compared to pristine HOPG surface. Our results showed that friction between two surfaces can also be a function of the bulk material. In the second part of the thesis, we demonstrated transparent heating element made out from Chemical Vapor Deposition (CVD) grown graphene on copper substrates. We used wet transfer method to transfer graphene on glass and quartz substrates for producing transparent heating element and modified transfer process for our purposes. Excitingly, our transparent heating elements can go up to high temperatures (310o C) with very low power consumption (27.2 Watt). We also studied heating properties of graphene samples grown by various growth paremeters. We observed that our graphene samples have monolayer background with multilayer zones. Also we observed silicon-oxide impurities may form on the CVD grown graphene and they can be transferred on any substrate. Changing growth parameters causes differences in the impurity concentration as well as monolayer and multilayer zone concentration which results in differences in heating properties of the graphene based heating elements.