電阻切換特性與陽極氧化鋁奈米孔徑關係之研究

陽極氧化鋁(Anodic Aluminum Oxide)，簡稱AAO，為一種具有規則排列的蜂巢狀多孔洞級材料。其擁有均勻筆直的通道結構，直徑最小可達到奈米等級，以及高介電係數的性質，使其在奈米材料製作的領域以及生物科學、電子、化學等其他領域都有很大的發展。本論文旨在探討AAO孔徑大小與其電阻切換間之關聯性。我們先在孔徑大小不同的AAO模板上下使用電子束蒸鍍機(E-beam Evaporator)分別鍍上100 nm的二氧化矽(SiO2)後，再使用小型真空蒸鍍機在其中一面蒸鍍底電極鋁(Al)，最後在另外一側利用金屬遮罩蒸鍍點狀金屬鋁作為頂電極，形成Al/ SiO2/ AAO/ SiO2/ Al的結構。此處使用上、下層SiO2是為了防止在蒸鍍電極過程中金屬進入AAO孔洞而影響所量測電性的正確性。我們使用Agilent4156B半導體參數分析儀對AAO元件進行電流-電壓(I-V)特性的量測。我們發現，以AAO為材料主動層之元件具有雙極性之電阻切換特性。對相同電極面積大小的AAO元件，通過元件之電流密度隨著孔徑大小增加而增加，其高阻態電阻(RHRS)及低阻態電阻(RLRS)亦隨著孔徑大小增加而減少。我們將在本論文中探討這些特性的原因。

關鍵字

陽極氧化鋁；奈米孔洞；奈米模板；電阻切換

並列摘要

Anodic aluminum oxide (abbreviated as AAO) is a material that has regular high density array with honeycomb-shape pores. The AAO has high dielectric constants and its pores have diameters in the range of a few to several hundred nanometers, forming straight hollow channels in AAO. These unique properties make AAO find a lot of applications in nanomaterials fabrication, bioscience, electronic and chemistry areas. The main theme of this thesis is to investigate the correlation between the resistive switching characteristics of AAO and its pore size. At first, we deposited a 100nm-thick silicon dioxide (SiO2) layers on top of the AAO template by e-gun evaporation. An aluminum (Al) back gate layer was then deposited on the bottom SiO2 by using a thermal evaporator. Finally, an Al layer was deposited onto the top SiO2 layer through a metal mask, also by thermal evaporation. The completed device has a structure of Al/SiO2/AAO/SiO2/Al. The top and bottom SiO2 layers used here are to prevent possible metal penetration into the hollow pore channels during metallization. Electrical characterization of the AAO devices was carried out by using the Agilent 4156B semiconductor parameter analyzer to measure their current-voltage (I-V) characteristics. It is found that the devices using AAO as active layer exhibit bipolar resistive switching. It is also noticed that, for the AAO devices with the same top electrode area, the current density flowing through the devices increases while the resistance of high-resistance state (RHRS) and resistance of low-resistance state (RLRS) decrease with increasing pore size. We will discuss the root causes of these characteristics in this thesis.