The Fabrication And Transport Properties Of Metallic Nanostructures

In this dissertation, the growth conditions for high quality metal thin film, the fabrication of nanocontact structure and their transport properties were investigated.Firstly, Thermal evaporation system was chosen to deposit metal thin film. A series of Au, Ag film samples were deposited with different conditions. The as-grown films were characterized by atom force microscope. The films with high quality can be obtained by adjusting the total pressure, growth speed, buffer layers, substrates and film thickness.Secondly, the fabrication processes of permalloy nanocontact structures were investigated by different deposition and fabrication methods and characterized by the SEM, AFM and EDAX. The film deposited by magnetic sputtering has high quality surface morphology but poor composition consistency with the target material compared with that for the film deposited by the thermal evaporation method. The high quality nanocontact structure with perfect surface morphology can be fabricated by lift-off process for the film deposited by thermal evaporation. However, to the film deposited by magnetic sputtering, an etching process is needed to form the nanocontacts.Finally, the transport properties of nanocontacts were measured by Kelvin method. The resistance of metallic nanocontact structure increases with increasing the current, and the change of resistance decreases with the increase of the nanocontact's width, which can be attributed to the heating effect.