臺灣博碩士論文加值系統

在過去幾年中，由於簡單性，可靠性，成本效益和批量生產可行性，各種金屬氧化物半導體(MOS)感測器已被廣泛研究並用於量測。三氧化鎢(WO3)是用於氧化物半導體的氣體感測器並且用於商業裝置研究最多的材料之一。它在檢測氫氣，甲醛和一氧化氮方面具有良好的性能。基於三氧化鎢(WO3)的氣體感測器由於其結構簡單，成本低，可靠性好以及相對於其他氣體感測器裝置易於製造而引起了極大關注。此外，本研究還將通過X射線繞射儀(XRD)，掃描電子顯微鏡(SEM)，能量色散X射線光譜儀(EDS)和原子力分析顯微鏡(AFM)來分析三氧化鎢(WO3)氣體感測器的元件結構，表面形貌和元素組成。

Over the past several years, various metal oxide semiconductor (MOS) sensors have been extensively studied and used for detection because of the simplicity, reliability, cost-effectiveness, and mass-production availability. Tungsten trioxide (WO3) is one of the most investigated materials for semiconducting oxide gas sensors and used in commercial devices. It offers a good performance in the detection of H2, HCHO, and NO. Tungsten trioxide (WO3)-based gas sensor have attracted significant attention of the researchers due to their simple structure, low cost, good reliability and easy fabrication process respect to other gas sensor devices. In addition, this study will analyze the device structure, surface morphology and elemental composition of WO3 based gas sensors by X-ray diffractometer (XRD), scanning electron microscope (SEM), energy dispersion X-ray spectrometer (EDS), and atomic force microscope (AFM).

Table List
Figure Captions
Chapter 1 Introduction
1.1 Introduction of Gas Sensors 1
1.2 Tungstn Trioxide (WO3) 2
1.3 Sensing Mechanisms 3
1.3.1 Hydrogen Sensing Mechanism 3
1.3.2 Formaldehyde Sensing Mechanism 4
1.3.3 Nitric Oxide Sensing Mechanism 4
Chapter 2 Gas Sensors Based on Thermal Evaporated-Pd Nanoparticles (NPs)
2.1 Introduction 5
2.2 Experimental Processes 6
2.2.1 Device Fabrication 6
2.2.2 Thermal Evaporated-Pd Nanoparticles 7
2.2.3 Sensing Measurement 7
2.2.4 Analytical Equipment 8
2.3 Experimental Results and Discussion 9
2.3.1 Hydrogen Sensing Characteristics 9
2.3.2 Structural and Morphological Characteristics 12
2.4 Summary 13
Chapter 3 Gas Sensors Based on Thermal Evaporated-Au Nanoparticles (NPs)
3.1 Introduction 14
3.2 Experimental Processes 15
3.2.1 Device Fabrication 15
3.2.2 Thermal Evaporated-Au Nanoparticles 16
3.2.3 Sensing Measurement 16
3.2.4 Analytical Equipment 17
3.3 Experimental Results and Discussion 17
3.3.1 Formaldehyde Sensing Characteristics 17
3.3.2 Structural and Morphological Characteristics 20
3.4 Summary 21
Chapter 4 Gas Sensors Based on Thermal Evaporated-Ag Nanoparticles (NPs)
4.1 Introduction 22
4.2 Experimental Processes 22
4.2.1 Device Fabrication 22
4.2.2 Thermal Evaporated-Ag Nanoparticles 23
4.2.3 Sensing Measurement 23
4.2.4 Analytical Equipment 24
4.3 Experimental Results and Discussion 24
4.3.1 Nitric Oxide Sensing Characteristics 24
4.3.2 Structural and Morphological Characteristics 27
4.4 Summary 28
Chapter 5 Conclusion and Prospect
5.1 Conclusion 29
5.2 Prospect 29
Reference 31

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