摘要

　　本研究於不同表面性質之鋁箔片基材及具不同中介層之矽基鋁膜上進行陽極化，觀察基材性質對鋁陽極化行為之影響，並利用不導電中介層之矽基氧化鋁模板電鍍，比較其與傳統模板輔助電鍍之差異。

　　本文共分四部分，包括：（1）表面拋光前處理對製備規則奈米孔陣列多孔氧化鋁之影響，（2）長時間陽極化之多孔氧化鋁成長行為，（3）中介層對矽基鋁膜陽極化行為之影響，以及（4）未加導電中介層之矽基氧化鋁模板上鎳金屬電鍍行為。

　　鋁基材經機械拋光，陽極化所得多孔氧化鋁孔洞形狀及排列均不規則，延長陽極化時間並未能得到大面積規則奈米孔陣列之多孔氧化鋁。電化學拋光後，鋁基材表面粗糙度為5nm以下。將具不同表面微結構之鋁金屬基材於相同條件下陽極化，可得規則奈米孔陣列面積約4～6 m2之多孔質氧化鋁，顯示基材表面粗糙度降至數個奈米時，多孔質氧化鋁之特徵由陽極化條件決定。

　　無論基材電化學拋光與否，陽極化電流僅於低溫下呈現穩定下降且氧化鋁呈現穩定成長。提升溫度導致陽極電流於陽極化後期呈上升趨勢且於氧化鋁/電解液界面產生缺陷。改變陽極化溫度並未能於機械拋光基材上製備大面積規則奈米孔之多孔氧化鋁模板。以電化學拋光基材於低溫下陽極化，規則奈米孔陣列面積與氧化鋁厚度於陽極化過程中均呈增加趨勢。溫度升高時，規則奈米孔陣列於陽極化中發生規則-不規則轉變，而氧化鋁有剝落現象。

　　對矽基鋁薄膜而言，當中介層為Si及Ti時，陽極化後期出現一電流回復現象，氧化鋁孔洞底部於Al-Si及Al-Ti界面處產生額外孔洞及斜向孔洞，孔洞底部由半球形轉變為拱形。當中介層為SiO2時，基材於鋁膜完全氧化後電流則趨近於零，孔洞底部僅有斜向孔洞。以Au為中界層，鋁膜完全氧化後，因Au界面產生水解反應，導致電流急速上升。並破壞Au中介層上因水解反應所產生之圖案。此外，水解反應降低氧化鋁模板在基材上之附著性，導致模板與基材分離。

　　以未加導電中介層之矽基氧化鋁模板電鍍金屬鎳時，氧化鋁模板於高過電位下因介電崩潰而帶電，鎳金屬在氧化鋁膜板表面沉積。矽基多孔氧化鋁模板於電鍍初期所得鎳金屬顆粒平均密度高於矽晶片所得者，顯示金屬於矽基多孔氧化鋁模板上較易成核。過電位較低時，鎳金屬僅於氧化鋁/電解液界面形成一含鎳奈米點之連續鎳金屬層。而過電位較高時，沉積物可填滿氧化鋁奈米孔，形成一含鎳金屬奈米線之連續鎳金屬層。在高過電位所得到之鎳奈米結構含實心多晶、單晶奈米線及鎳奈米管。奈米管之生成顯示即使於高過電位下，沉積仍由氧化鋁模板表面開始，亦可能生成單晶奈米線。

Abstract

　In this study, one step anodization was carried out on both the Al foils with different surface features resulted from different polishing conditions and the Si-based Al films containing different interlayers to investigate the effect of substrate parameters on the anodization behaviors.

　This study is divided into four parts, including (1) the effect of polishing pretreatment on the fabrication of ordered nanopore arrays on aluminum foils by anodization, (2) growth characteristics of oxide during prolonged anodization of aluminum in preparing ordered nanopore arrays, (3) anodization behavior of Al film on Si substrate with different interlayers, and (4) the electrodeposition behavior of Ni on silicon-based porous anodic alumina templates without a conductive interlayer.

　When the non-electropolished Al substrate is anodized, only limited-sized ordered domains could be obtained even prolonging the anodization duration. After electropolishing, the average surface roughness is below 5nm for all the Al foils. Nearly perfect hexagonal close-packed ordered pore arrays with domain size of about 4~6μm2 could be obtained on the electropolished Al substrate even with different surface features, indicating that the characteristics of porous anodic alumina are determined by the anodization parameters when the average surface roughness is reduced to several nanometers.

　At a low anodization temperature, the continuous decrease of oxidation current in the whole anodizing process is attributed to the stable oxide growth. A continuous increase of the oxidation current with fluctuation is observed in a prolonged period of anodization at high temperatures; at the same time, some cracks are formed at the oxide/electrolyte interface. A highly ordered pore configuration obtained on the electropolished Al foil for longer anodization time could only be maintained at a low temperature. When anodizing at a high temperature, the ordered pore arrangement of the oxide obtained initially on the electropolished Al foil is found to become disordered in the prolonged anodization. The total film thickness increases in the beginning and decreases in the prolonged period due to the spalling of the oxide when the anodization is conducted at a high temperature.

　For the preparation of nanoporous template on the Si-based Al film containing Si and Ti interlayer, an immediate recovery of current occurs on the Al-Si interlayer after the Al film is completely consumed. The pore bottom becomes arched due to the additional dissolution under the pore base and the oblique dissolution beside the pore base. When the interlayer is SiO2, the current approaches zero when the Al film is consumed completely, only the oblique pore is formed in the pore base. For the Si-based PAA template containing Au interlayer, the hydrolysis reaction would destroy the patterns formed on the Au interlayer and lead to the separation between the PAA and the substrate.

　Through the electrical breakdown of the template, Ni nanodots, nanowires and nanotubes could be obtained by only changing the electrodeposition voltage on the same substrate. At a less negative voltage, a Ni layer containing only nanodots is formed at the oxide/electrolyte interface. The electrodeposition still occurs on the pore wall instead of the underlying substrate, leading to the formation of some Ni nanotubes at a more negative voltage. Besides, single-crystalline Ni nanowires could also be formed even when the electrodeposition voltage is as negative as -40V, indicating that the formation of single-crystalline metallic nanowires under a large overpotential is possible.

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