本實驗以氧化亞銅奈米顆粒修飾氧化鋅奈米線為基礎，並利用黃光微影技術製作電阻式一氧化氮氣體感測器。先將氧化鋅奈米線經由水溶液法長在經黃光微影做的鈦金屬電極矽基板上，再經由光還原法將氧化亞銅奈米顆粒修飾於氧化鋅奈米線上。為了使氧化鋅和氧化亞銅的結晶性變好，還會進行退火處理。其感測原理是由於一氧化氮為氧化性氣體，吸附在元件表面時會造成導電性下降。藉由偵測電流的變化，則可以計算感測器的響應。　　
　　藉由掃描式電子顯微鏡與穿透式電子顯微鏡觀察氧化鋅奈米線和氧化亞銅奈米顆粒的表面形貌並確認其結構，其中又以10-4 M硫酸銅溶液光還原2小時可以得到最佳的氧化亞銅奈米顆粒修飾濃度，推測有最佳的氣體感測；從螢光光譜圖的分析，能看出修飾過後的氧化鋅奈米線在紫外光放光波段強度下降，綠光波段強度上升，由此推斷氧化亞銅奈米顆粒能有效使電子電洞對的再結合率降低，以及增加氧空缺的數目。
　　在大氣環境下，利用紫外光激活模式進行濃度1 ppm一氧化氮的感測結果中，未修飾的氧化鋅奈米線的響應為的25%，而修飾後氧化鋅奈米線感測元件響應為357%，是未修飾氧化鋅奈米線的14倍。在60 ppb一氧化氮氣體感測中響應也達到8%。另外，我們利用紫外光回復模式進行濃度1 ppm一氧化氮的感測，修飾後氧化鋅奈米線感測元件響應為28%，對60 ppb一氧化氮的響應也有4%。本實驗成功地以簡單的光還原方法製備出響應較好的NO氣體感測器，並顯示對低濃度的一氧化氮感測有很大的潛力。

In this work, nitric oxide (NO) gas sensors based on the ZnO nanowires (NWs) modified with Cu2O nanoparticles (NPs) are reported. The ZnO NWs are grown on Ti electrodes substrates of 300 nm thick created by photolithography using a solution method and then modified with Cu2O NPs by photoreduction. To facilitate crystallization, the ZnO NWs and Cu2O NPs are also subjected to thermal annealing. The sensing principle is due to the fact that NO is an oxidizing gas and the adsorption of gas molecules on the NWs surface causes the NWs conductance to decrease. By monitoring changes in the sensor current, we can calculate the response of the gas sensor.
The results of scanning electron microscopy show the morphologies and structures of nanowires and nanoparticles. The ZnO NWs modified with the best concentration of Cu2O NPs show the best NO gas sensing under the condition of two hours photoreduction with 10-4 M copper sulfate. The ultraviolet emissions of the modified ZnO NWs decrease and the green emissions of the modified ZnO NWs increase in the photoluminescence spectra, revealing that the recombination of electron-hole pairs is reduced and the number of O vacancies (Vo) is increased by Cu2O NPs.
The results of 1 ppm NO gas sensing by using UV activation under ambient environment show the response of the unmodified ZnO NWs sensor is 25%, whereas the response of the Cu2O NPs modified ZnO NWs sensor is 357%, which is 14.28 times as high as that of the unmodified ZnO NWs sensor. A response of 8% has also been achieved at 60 ppb NO. On the other hand, the results of 1 ppm NO gas sensing by using UV recovery show the response of the Cu2O NPs modified ZnO NWs sensor is 28%. A response of 4% has also been achieved at 60 ppb NO. A high-efficiency NO gas sensor is successfully fabricated by a simple photoreduction method, and shows a good potential of the Cu2O NPs modified ZnO NWs for low concentration NO gas sensing.

中文摘要 I
Abstract II
致謝 IV
目錄 V
圖目錄 VIII
表目錄 XII
Chapter 1 緒論 1
1.1 前言 2
1.2 研究動機 3
Chapter 2 文獻回顧 5
2.1 氧化鋅奈米線概論 6
2.1.1 晶體結構 6
2.1.2 成長機制與方法 7
2.1.3 氧空缺本質摻雜形成n-type半導體 10
2.1.4 氧化鋅光學性質 11
2.2 氣體感測原理 13
2.2.1 氧空缺與氣體吸附作用 13
2.2.2 氧化鋅對一氧化氮的反應機制 16
2.3 感測元件紫外光激活回復特性 17
2.4 以複合材料結構提高氣體感測響應 20
2.5光還原法 22
Chapter 3 實驗製程與量測 24
3.1 感測元件製作流程 25
3.1.1定義電極圖樣 25
3.1.2鈦電極蒸鍍 26
3.1.3去除光阻 26
3.1.4 氧化鋅奈米線成長 27
3.1.5 製作氧化亞銅奈米顆粒修飾氧化鋅奈米線 29
3.1.6 元件組裝 30
3.2分析儀器與樣品準備 31
3.2.1掃描式電子顯微鏡 31
3.2.2穿透式電子顯微鏡 31
3.2.3螢光光譜儀 31
3.3一氧化氮氣體感測 32
3.3.1 氣體感測系統架構 32
3.3.2 一氧化氮濃度計算 33
3.3.3 氣體感測操作流程 34
Chapter 4 實驗結果與討論 36
4.1氧化鋅奈米線形貌及光學特性 37
4.1.1表面形貌及結構分析 38
4.1.2光致發光性質 45
4.2 NO氣體的感測結果 50
4.2.1紫外光激活(UV activation)模式 51
4.2.2紫外光回復(UV recovery)模式 63
4.2.3實驗數據與文獻比較 66
Chapter 5 結論 68
參考文獻 71

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