在1991年時，Iijima以電弧放電法製備出奈米碳管之後，奈米科技越來越受到重視。奈米技術對於半導體以及光電產業帶來了重大的影響，尤其是一維奈米材料的場發射特性應用最受到重視，其場發射特性可用來製作場發射顯示器(FED)。除此之外，奈米線的奈米級尖端非常適合用來當作STM、AFM的探針。
在研究中我們使用陽極氧化鋁(AAO)來成長氧化鎢奈米線，利用氧化鋁來控制氧化鎢奈米線的密度，進一步降低電場屏障效應所帶來的影響，成功的提升氧化鎢奈米線的場發射特性。藉由濺鍍沉積純鎢薄膜於孔洞大小100 nm以及200 nm孔徑AAO表面，並且將AAO孔洞填滿，之後在氮氣氛圍下進行650oC ~ 800oC、30分鐘的熱退火。由SEM可以看出在800oC時具有最佳長寬比的奈米線，經由場發射量測結果可以發現，在800oC時，以100 nm以及200 nm孔徑 AAO所成長的氧化鎢奈米線其啟動電場分別為1.7 V/m以及2.3 V/m @J=1A，並可以發現由於100 nm 孔徑AAO具有比200 nm孔徑 AAO更適合的奈米線密度，所以具備有更好的場發射特性。
此外我們也利用AAO高密度且孔洞均勻規則的特性，以電鍍法可以以低成本的方式製備大面積的鎳奈米線，並利用AAO作為Sapcer，且以100 nm以及200 nm孔徑AAO來研究在不同長度之下其場發射特性的變化，結果顯示以兩種尺寸所成長的鎳奈米線，在長度逐漸增加的情況下，其啟動電場呈現先下降後上升的情況。這表示在較低長度之下，增加奈米線的長度有助於提升其場發射特性，但是到了一定長度之後，此時繼續的增加奈米線的長度將使得電場屏障效應增加，導致場發射特性隨著長度的增加而衰減。
此外也利用NaOH溶液蝕刻去除AAO，結果顯示，在移除AAO後的場發射特性有很明顯的提升。在電鍍100 nm直徑鎳奈米線一小時的條件下，移除前啟動電場為6.3 V/m @J=1A/cm2，而其場發射電流密度在20V/m外加電場強度時僅約65A/cm2，但是移除AAO之後，其啟動電場可以降至4.8 V/m @ J=1A/cm2，而且其場發射電流密度在8 V/m外加電場強度時將可大幅提升至200 uA以上。

Nanoscale materials such as nanotubes, nanowires, nanobelts, and nanorods, etc., have attracted lots of attention since the carbon nanotube was fabricated by arc discharge method in 1991. These nanoscale materials, especially, one dimension nanowires, have much potential in field emission applications such as field emission display (FED), single-electron transistors (SETs) and so on.
In this study, the field-emission properties of nanowires produced using anodic porous anodic aluminum oxide (AAO) templates are reported. Tungsten oxide (WOx) nanowires for field emitters based on a pore-space confinement of AAO templates is reported. The WOx nanowires were grown inside the pores of AAO templates by a simple thermal annealing process of sputter-deposited W films. The lower field-screening effect of the WOx nanowires is achieved because the density of WOx nanowires could be controlled by using AAO templates. Experimental results show that good field emission characteristics with an enhancement factor of around 3358, and a turn-on field intensity of 1.7 V/m were obtained at 800oC.
In addition, the Ni nanowires were fabricated in AAO templates by electrodeposition method. The field emission characteristics of the Ni nanowires with different length were grown in different diameter (100 and 200 nm) of AAO templates. The field emission characteristics of the Ni nanowires are discussed with different diameter and different length. The results show that the best field emission characteristic is measured with an enhancement factor of around 2118, and a turn-on field intensity of 6.3 V/m were obtained.

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