| Summary: | 碩士 === 國立臺灣科技大學 === 材料科學與工程系 === 107 === In this thesis, two kinds of 1D materials were being investigated, including the Cu¬3Ge nanowires and Cu3Ge-Ge heterostructure nanowires. First part was the fabrication of the nanowires. The pre-operation of the bulk was to take the powder of copper and germanium separately into the quartz tube with a specific atomic percentage component and do the smelting above the melting point of Cu and Ge under the vacuum by the oxyhydrogen flame gun. Then, it was placed in the furnace tube and heated to 50 °C above the melting point of the material to make the solid diffusion of Cu and Ge at a sufficient temperature and time, cooling down to about 150 °C below the melting point of the material, and the temperature was maintained for 12 hours. The undercooling of the temperature gradient was created to control the grain size and morphology of the material. Scanning Electron Microscope and Energy Dispersive X-ray Spectrometer were used to confirm the initial bulk components, and X-ray Diffraction and Raman spectrum were further used for more accurate quantitative analysis. Take out the bulk and removed the surface oxide of bulk. Using AAO with a pore size of 100 nm as a template, and put it into a heating furnace under vacuum and at 700 °C for 10 minutes to ensure the internal and external temperature of the heating furnace was uniform. Next, under a vacuum state, a hydraulic press was placed to perform pressure casting. The nanowire pressed into the AAO template was placed in H2Cr2O7 for 3.5 hours to completely remove the AAO template. On the other hand, the AAO template with the pressed material was placed in a furnace tube for thermal annealing treatment, and heat treatment was performed at 450 ° C for 1.5 hours and 6 hours, respectively. The purpose was to enable the copper defects of the nanowire to be largely eliminated and to obtain a single crystal nanowire with uniform grain size and grain boundary elimination. Due to the heat treatment, the AAO template will recrystallize, so it is necessary to put the sample into H2Cr2O7 (aq) for 4.5 hours to completely remove the AAO template. The second part is that prepared nanowires are used for preliminary SEM, XRD and Raman spectrum analyses. TEM is used to confirm the growth direction of materials and defects in materials. Finally, the electrical analyses which were used a Focused Ion Beam system to connect the pre-pattern substrate and the nanowires with a platinum to do two points and four points of electrical analyses. Compared the material resistivity between as-prepared and different annealing parameters.
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