| dc.description.abstract | There are two parts in this study, the first part is bowl-liked surface synthesis on single crystalline Si. Large area vertically-aligned ZnO and Al-doped ZnO (AZO) nanowires were successfully synthesized by hydrothermal method on glass and Si substrates in the second part. The morphologies, crystal structures, compositions, properties, and growth kinetics of the ZnO and AZO nanowires have been systematically investigated by SEM, TEM, SAED, XRD, UV-vis and EDS analyses.
Single crystalline Si was sandblasted through sandblast machine, and bowl-liked surface was manufactured successfully through wet etching. From dektak analysis, the surface roughness become larger with increasing the time of etching. The roughness will become smaller when the bowls become too large. The low reflectance was also analysised through UV-Vis.
From TEM and XRD analysis, all the ZnO and AZO nanowires synthesized were single crystalline with a hexagonal structure and their growth direction was parallel to [0001]. In addition, the lengths of the ZnO and AZO nanowires were found to increase linearly with reaction time at 65-80 0C. By measuring the growth rate at different reaction temperatures, the activation energies for the linear growth of ZnO, AZO (2%Al), AZO (5%Al) and AZO(10%Al) nanowire arrays were derived to be about 35.1、48.6、55.6、59 kJ/mol, respectively. The resistances of AZO film and AZO nanowires were measured to decrease with the exposure time of UV light. On the other hand, an abnormal surface wettability were found in the ZnO-based samples. The water contact angles of the ZnO-based tended to increase with increasing the storage days. In this study, we also demonstrate the wettability of ZnO and AZO nanowires can be modulated by annealing in vacuum and in oxygen atmosphere. | en_US |