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研究生:陳柏霖
研究生(外文):Chen, Po-Lin
論文名稱:利用陽極氧化鋁模板製備奈米級二氧化鈦有害氣體感測元件之研究
論文名稱(外文):The Study of Fabrication of Nano Titanium Dioxide Harmful Gas Sensor by Template of Anodic Aluminum Oxide
指導教授:郭金國郭金國引用關係
指導教授(外文):Kuo, Chin-Guo
學位類別:碩士
校院名稱:國立臺灣師範大學
系所名稱:工業教育學系
學門:教育學門
學類:專業科目教育學類
論文出版年:2021
畢業學年度:109
語文別:中文
論文頁數:82
中文關鍵詞:陽極氧化鋁二氧化鈦氣體感測元件甲醛一氧化碳
外文關鍵詞:AAOTiO2Gas sensorFormaldehydeCarbon monoxide
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本研究旨在製備出奈米級二氧化鈦氣體感測元件來感測有害氣體,在陽極氧化鋁(Anodic Aluminum Oxide, AAO)模板濺鍍白金(platinum, Pt)作為導電極,再以蒸鍍鋁(Aluminum, Al)作為薄膜支撐的底座,經由濕式蝕刻的方法去除AAO的阻障層以及擴孔處理,最終以原子層沉積法將二氧化鈦(Titanium Dioxide, TiO2)沉積於製備好的模板中形成奈米結構。製作的過程中探討不同製程參數所形成的二氧化鈦奈米結構的表面形貌與晶體結構,其性質以掃瞄式電子顯微鏡(Scanning Electron Microscopy, SEM)、能量色散X射線光譜(Energy-dispersive X-ray Spectroscopy, EDS)檢測。製作完成之奈米級有害氣體感測元件,以氣體感測設備來量測甲醛(Formaldehyde, CH2O)、一氧化碳(Carbon monoxide, CO)氣體之反應靈敏度,實驗結果顯示奈米級二氧化鈦有害氣體感測元件,以溫度和氣體濃度的實驗參數搭配。在室溫(25˚C)下感測CH2O靈敏度最高為37.1%;感測CO靈敏度最高為24.0%。然而在加熱的狀態下,感測CH2O在0.5 ppm、500˚C時其靈敏度最高為63.2%;感測CO在600 ppm、500˚C時其靈敏度最高為90.2%。
In this study, a metal oxide semiconductor gas sensor was fabricated to detect harmful gases. A metal oxide semiconductor was a nano titanium dioxide (TiO2) produced by atomic layer deposition (ALD) in anodic aluminum oxide (AAO) template. An anodic aluminum oxide was suitable for producing nanotube or nanowire process. It had high porosity, good regularity and good array. In producing process of sensor, sputter platinum (Pt) on the AAO as layer of conductive, then thermal vapor aluminum (Al) as the base to support the film. The barrier layer of AAO is removed by wet etching and the hole expansion is processed. Finally, TiO2 was deposited on the prepared template by atomic layer deposition to form a nano structure. Using this sensor to detect formaldehyde (CH2O) and carbon monoxide (CO) at the different concentration and temperature. The experimental results show that the highest sensitivity for detecting CH2O and CO at the room temperature (25˚C) were respectively 37.1% and 24.0%. The highest sensitivity for detecting CH2O and CO at the heat situation were respectively 63.2%, 0.5 ppm at 500˚C and 90.2%, 600 ppm at 500˚C.
第一章 緒論 1
1.1 前言 1
1.2 研究動機與目的 5
1.3 研究流程與架構 6
第二章 文獻回顧 9
2.1 有害氣體的概述 9
2.1.1 甲醛的危害及其檢測方法 13
2.1.2 一氧化碳氣體的危害及其檢測方法 17
2.2 氣體感測器 21
2.2.1 氣體感測器的種類 21
2.2.1.1 金屬氧化物半導體式氣體感測器 21
2.2.1.2 紅外線式氣體感測器 24
2.2.1.3 光纖氣體感測器 24
2.2.1.4 觸媒燃燒式氣體感測器 25
2.2.1.5 氣體感測器的特性比較 26
2.2.2 金屬氧化物氣體感測材料種類 27
2.3 陽極氧化鋁 27
2.3.1 陽極氧化鋁生長機制 28
2.3.2 陽極氧化鋁模板的製作參數 30
2.3.3 陽極氧化鋁模板的特性 33
2.4 二氧化鈦 34
2.4.1 二氧化鈦概述 34
2.4.2 二氧化鈦奈米結構製作方法 36
第三章 實驗方法 39
3.1 實驗流程 39
3.2 奈米級陽極氧化鋁模板的製作 41
3.2.1 實驗步驟 41
3.3 製備感測元件導電層 43
3.3.1 實驗步驟 43
3.4 濕式蝕刻 45
3.4.1 實驗步驟 45
3.5 以原子層沉積法製備奈米級二氧化鈦 47
3.5.1 實驗步驟 47
3.6 氣體量測 49
3.6.1 實驗步驟 50
3.7 儀器分析 51
3.7.1 掃描式電子顯微鏡 51
3.7.2 EDS元素成分分析 52
3.7.3 氣體量測 52
第四章 實驗結果與討論 55
4.1 製備陽極氧化鋁模板過程之SEM觀察 55
4.1.1 陽極氧化鋁之SEM形貌結果 55
4.1.2 去除阻障層之SEM形貌結果 56
4.1.3 ALD法沉積TiO2之SEM形貌結果 58
4.2 EDS元素成分分析 59
4.3 有害氣體量測 61
第五章 結論 73
參考文獻 75
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