Summary: | 碩士 === 國立中央大學 === 材料科學與工程研究所 === 101 === Nanosize templates are a low-cost and promising approach for deposition of low-dimensional nanomaterials or transfer of nanopatterns onto a substrate without using costly lithography equipments. Among them, anodic aluminum oxide (AAO) membrane is one of the most attractive nanopore materials due to its highly ordered structure, high pore density and tunable pore size, which make them potentially for a variety of applications. The pore size and interpore distance of AAO membranes are linearly dependent on the applied voltage during the anodization process. In the conventional constant voltage method, the AAO membranes with a large interpore spacing of 300~500 nm could be obtained using an anodizing voltage of 150~195 V. When applying a high voltage over 180 V, however, the burning phenomenon, which would cause structural damages, usually appears owing to the high current flows concentrated at the some weak areas.
In this study, The AAO membranes were fabricated through an anodization procedure in phosphoric acid (H3PO4) solution. A current-controlled method has been developed for fabrication of AAO membranes with a large pore interval in order to avoid the burning phenomenon. From the experimental results, the average growth rate of AAO membranes could increase up to 6 μm/hr with an applied current density of 6 mA/cm2 and the burning phenomenon could be totally avoided at a relatively high anodizing voltage of 192 V. The effect of current density on the growth rate and burning phenomenon was also investigated.
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