隨著工業快速發展，對環境造成的汙染日趨嚴重，因此，氣體感測器的研發越顯重要。此篇論文分別採用氧化銦鎵鋅及氧化銦鋁鋅研製出具有低成本、高靈敏度及良好穩定性的氣體感測器。本研究經由濺鍍氧化銦鎵鋅和氧化銦鋁鋅感測薄膜並透過熱蒸鍍三種不同的奈米金屬粒子（鈀、金、鉑）修飾而形成的感測元件。奈米金屬粒子顯著地提高了溢出效應、表面積/體積比和催化反應性。
首先，第一種元件利用濺鍍氧化銦鎵鋅薄膜結合金奈米粒子製備出電阻式乙醇氣體感測器。此元件展現出極佳的感測響應，在攝氏250度下，通入濃度為2400 ppm的乙醇氣體，感測響應為465.4，同時也具有極低的感測極限，可以檢測到濃度僅有100 ppb的乙醇氣體，本元件還具有不錯的感測速度及良好的選擇性。
接著，第二種元件將感測層改為濺鍍氧化銦鋁鋅薄膜，並利用熱蒸鍍鈀奈米粒子製備出電阻式氫氣感測器。此元件顯示出優異的氫氣感測特性，在攝氏250度下，通入濃度為1%的氫氣，感測響應為9.6 × 105，最低可以檢測到濃度1 ppm的氫氣。
然後，第三種元件延續第二種元件的基礎，將熱蒸鍍沉積鈀奈米粒子改成金奈米粒子，從而製備出電阻式甲醛感測器。此元件展現出優異的甲醛感測特性，在攝氏275度下，通入濃度為20 ppm的甲醛，感測響應為29850，最低可以檢測到濃度200 ppb的甲醛。
最後，第四種及第五種元件結合了氧化銦鋁鋅薄膜和鉑奈米粒子的氨氣和氫氣感測器分別在不同的退火溫度下被製造。氨氣感測器在攝氏300度下，通入濃度為1000 ppm的氨氣，感測響應為112，同時也具有不錯的感測極限，可以檢測到濃度1 ppm的氨氣，而氫氣感測器在攝氏250度下，通入濃度為1%的氫氣，感測響應為32147，最低可以檢測到濃度10 ppm的氫氣。
本論文分別研製了五種不同的氣體感測器。五種元件皆展示了相當優異的感測能力，同時還具有製造容易和結構簡單等優點。根據實驗結果，在氧化物薄膜添加特定的金屬奈米粒子可以顯著提高感測能力，造成更高的表面積和體積比讓更多的氣體分子吸附，並且加強溢出效應催化氧離子吸附在金屬氧化物薄膜上。

With the flourishing development of industrialization, environmental pollution is becoming more and more serious. Thus, the research of gas sensors becomes increasingly important. In this thesis, indium aluminum zinc oxide (IAZO) and indium gallium zinc oxide (IGZO) are employed to fabricate gas sensors with good stability, low cost, and high sensitivity. The devices of this thesis synthesized by a radio frequency sputtered metal oxide thin film and rapid thermal evaporated three different metal nanoparticles (Pd, Au, Pt), are researched and fabricated herein. The employed metal nanoparticles considerably improve the surface area/volume ratio, catalytic reactivity, and spill-over effect.
First of all, a gaseous ethanol sensor synthesized by a radio frequency (RF) sputtered amorphous (a)-IGZO thin film and rapid thermal evaporated Au nanoparticles (NPs) is fabricated. The device exhibits an outstanding sensing response value of 465.4 under 2400 ppm concentration of gaseous ethanol and a very low detecting level of 100 ppb C2H5OH/air at 250℃. The device has not only good sensing speed but also excellent selectivity.
Then, a hydrogen sensor based on an RF-sputtered a-IAZO thin film decorated with evaporated Pd NPs is fabricated. The device exhibits excellent hydrogen sensing characteristics. The very high hydrogen sensing response value of 9.6 × 105 under 1% concentration of hydrogen and a lower detecting level of 1 ppm H2/air were found at 250℃.
Afterward, a formaldehyde sensor combined with an a-IAZO thin film and Au nanoparticles is fabricated. The device exhibits excellent formaldehyde sensing characteristics. The very high formaldehyde sensing response value of 29850 under 20 ppm concentration of formaldehyde and a lower detecting level of 200 ppb HCHO/air were found at 275℃.
Finally, ammonia and hydrogen sensors combined with an a-IAZO thin film and Pt nanoparticles are fabricated at different annealing temperatures. The ammonia sensor exhibits the high SR value of 112 under 1000 ppm concentration of ammonia with a low detecting level of 1 ppm NH3/air at 300℃, and the hydrogen sensor exhibits the high SR value of 32147 under 1% concentration of hydrogen with a low detecting level of 10 ppm H2/air at 250℃.
Moreover, five gas sensors with different structures are researched and fabricated in this thesis, and they also exhibit the benefits of an uncomplicated structure and comparatively simple fabrication process. From the experimental result, the thermal evaporated Au, Pd, and Pt nanoparticles can considerably enhance sensing performance because the higher surface area/volume ratio can obtain more adsorption of gas molecules and the spill-over effect can catalyze the sorption of oxygen ions on the metal oxide support.

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