本論文利用直流磁控濺鍍系統鍍製150及300 nm厚的鎢薄膜至Al2O3基板上並配合紅外線加熱爐在環境溫度700°C下進行退火製程，並討論退火恆溫時間為30、45、60、75及90分鐘對一維WOx奈米線產生的平均長度及組成相態的影響，利用XRD、SEM及HRTEM進行WOx組成相態、結構及形貌的分析，最後則是討論W18O49與WO3氣體感測器在NO2環境下的感測能力。研究中發現厚度為150 nm的鎢薄膜在環境溫度700°C下恆溫60及90分鐘之WOx組成相態分別為W18O49及WO3。 W18O49繞射角度為23.454°，主要沿著 (010) 晶面成長；WO3繞射角度為23.120°、23.586°及24.380°，分別對應 (002)、(020) 及 (200) 晶面，其結果皆與HRTEM結果相符合。對NO2氣體感測能力分析，本論文分別探討一維W18O49及WO3奈米線氣體感測器在最佳工作溫度下 (150°C) 改變不同濃度NO2 (10、20、50及100 ppm) 之感測特性。實驗發現一維W18O49及WO3奈米線氣體感測在最佳工作溫度下 (150°C) 皆會隨著NO2濃度的增加使靈敏度呈線性成長。W18O49分別在NO2濃度為10、20、50及100 ppm下的靈敏度為1.436、1.671、1.816及1.973； 則是1.462、1.726、1.970及2.365。

In this study, tungsten films (150 and 300 nm thick) by DC magnetron sputtering were made, and annealing treatment at 700°C environment was used to discuss the influence of annealing duration (30, 45, 60, 75 and 90 mins) on the morphology, phase and microstructure. Finally, we compared one-dimension W18O49 nanowires with one-dimension WO3 nanowires on NO2 gas sensing ability. During this research, W18O49 and WO3 were made as 150 nm thick films by annealing for 60 and 90 mins at 700°C environment, respectively. One-dimension W18O49 and WO3 nanowires were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). For the XRD, the W18O49 with strongest diffraction peaks appears at 2θ=23.454°, phase with (010) growth plan; WO3 with strongest diffraction peaks appears at 2θ=23.120°, 23.586°, 24.380°, phase with (002), (020), (200) growth plane. The results were the same as HRTEM. In gas sensing ability, this research focused on the different NO2 concentrations (10, 20, 50 and 100 ppm) at a working temperature of 150°C. W18O49 and WO3 gas sensing performance were dependent on NO2 concentrations. W18O49 sensing ability on different NO2 concentrations (10, 20, 50 and 100 ppm) were 1.436, 1.671, 1.816 and 1.973, respectively. WO3 sensing ability on different NO2 concentrations (10, 20, 50 and 100 ppm) were 1.462, 1.726, 1.970 and 2.365, respectively.

第一章 緒論 1
1-1：前言 1
1-2：研究動機與目的 2
1-3：本文架構 4
第二章 文獻回顧 5
2-1： 晶體結構及半導體特性 5
2-2：金屬氧化物氣體感測原理 6
2-3： 氣體感測器相關研究 8
第三章 實驗方法 31
3-1：直流磁控濺鍍製程 32
3-2：退火製程 34
3-3：檢測結構形貌及材料分析之儀器設備 37
3-4：氣體感測量測設備 38
第四章 結果與討論 42
4-1：直流磁控濺鍍製程 43
4-2：退火製程 44
4-3：材料分析 52
4-4：氣體感測特性分析 55
第五章 結論及未來展望 69
5-1：結論 69
5-2：未來展望 71
參考文獻 72

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