本論文致力研製多種不同樣貌的氧化鋅奈米結構及其材料特性分析，利用低成本且易操作的水熱法成功生長金屬氧化物，並且摻雜不同的金屬離子於材料之中，優化感測元件的性能。本研究製作的感測器元件整合了微機電系統技術，使其實用性大幅提升。
我們使用高密度多孔狀的氧化鋅奈米片狀結構，成長於鋁薄膜上並整合微機電加熱技術製作臭氧氣體感測器。藉由改變鋁薄膜的厚度使得新穎的氧化鋅奈米結構改變高度，而臭氧感測器於300°C操作溫度下，響應值可達96.1%，並且在150°C仍有53.4%的表現。
本論文的第二部分研究則是，我們以銀摻雜氧化鋅奈米花結構作為一氧化氮氣體感測器元件，以紫外光優化其性能，得到了成功摻雜銀離子於氧化鋅奈米結構之內並改變其樣貌及特性的結論。
另考量實際應用層面，應用於大氣環境及人體時，感測器將會面臨到大量的水分子干擾，基於上述考量，我們利用氧化鋁摻雜氧化鋅奈米花狀結構並與金奈離子結合後應用於乙醇感測器，此感測器在不同相對濕度下皆有良好的精準度及響應。
論文最後一部分的研究結果顯示，將鋁摻雜氧化鋅奈米片狀結構的pH感測器，整合微流道系統，將能優化性能與提升實用性。此pH感測器有別於傳統的感測器，僅需極少量待測液體樣本，對於靈敏度、長時間使用性能和量測範圍等各方面向皆有卓越之表現，更符合實際的生物環境應用。

In the dissertation, various sensors based on the different morphology and properties of the Zinc Oxide (ZnO) nanostructure have been synthesized and discussed. The metal oxide has been fabricated by the low-cost and convenient hydrothermal method and optimized the sensing properties by metal ion doping. Furthermore, the MEMs technology has been integrated into the sensors, leading the application much more practical.
Firstly, an ozone (O3) sensor based on high-density porous zinc oxide (ZnO) nanosheets (NSs) has been synthesized on an aluminum (Al) film, and the sensor integrates with microelectromechanical systems (MEMS) technology. The height of this new ZnO nanostructure can be controlled by using different thicknesses of an Al seed layer ranging from 25 nm to 100 nm. This work resulted in a low temperature, hydrothermally grown novel porous ZnO NSs ozone gas sensor that measured O3 responses of 96.1% at 300 °C and 53.4% at 150°C.
Secondly, an ultraviolet-enhanced (UV-enhanced) nitric oxide (NO) sensor based on silver-doped zinc oxide (ZnO) nanoflowers is developed using a low-cost hydrothermal method. The results indicate that silver (Ag) ions were doped into the ZnO nanostructure successfully, thus changing the morphology.
Thirdly, Aluminum oxide-doped (Al2O3-doped) cactus-like ZnO nanoflowers with gold (Au) nanoparticles (NP) are grown on an aluminum (Al) substrate using a hydrothermal method to detect ethanol sensing in atmospheres with various degrees of relative humidity (RH). The novel cactus-like ZnO nanoflowers are sufficiently sensitive to ethanol in an atmosphere with high humidity to allow effective and accurate analysis of the amount of alcohol in breath.
Finally, a flexible and stable pH sensor based on aluminum-doped zinc oxide nanosheet (Al-doped ZnO NS) was developed by a low-cost hydrothermal method. The results obtained from this study indicated that Al ions could be doped successfully into the ZnO nanostructure, which could change the morphology and improve the pH-sensing properties. The benefits of Al-doped ZnO nanosheet, pH sensor were recognized as high sensitivity, good long-term usage, good flexible property and requirement of small amount of test liquid, which could make the sensors as viable candidates for practical applications.

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