Abstract
The thesis includes four parts. In the first two parts, the researches mainly focus on the properties of ITO nanowires. The applications of ITO/(ZnO-HfO2) core-shell nanowires are discussed in the third and fourth parts. For the properties of ITO nanowires, different sizes of Au nanoparticles were used to synthesize the nanowires with well controlled diameters. It is found that the resistivity is influenced by different diameters of ITO NWs controlled by different sizes of Au NPs. Competition of conductive factors such as Sn ions and oxygen vacancy confirmed by the X-ray photoemission spectra (XPS) analyses were investigated and discussed at different diameters of ITO NWs. In the secondary part of the thesis, the screen effect of ITO NWs was discussed. By selective area growth of ITO nanowires patterned by grid, the length and the density of ITO NWs can be controlled, diminishing the screen effect so as to enhance field emission properties, namely less the threshold filed. In the third part of thesis, the ITO/ZnO and ITO/HfO2/ZnO core-shell nanowires were synthesized by atomic layer deposition (ALD), which are found to enhance the field-emission property. The distribution of nanocrystals and oxygen deficient states were investigated and characterized by TEM and X-ray photoemission spectra (XPS). In the final part of the thesis, ITO/HfO2 core-shell nanowires were applied for resistive change memory (RRAM). Interesting, the electrical performance of ITO/HfO2 core-shell nanowire shows can be improved, compared with thin film device. Finally, complementary resistive switching (CRS) was demonstrated, making fabrication of future high-density resistive memory devices possible.