此篇論文以半導體材料製備出氣體感測器分別針對氫氣、氨氣、甲醛、酒精等生活中常見或是工業中常使用到的揮發性有機化合物(VOCs)進行感測實驗及各項數據分析。元件薄膜所使用的半導體材料為氧化銦錫鋅(ITZO)，透過銀奈米顆粒於薄膜底下可以增加薄膜的感測面積，再結合催化金屬(鈀、鉑、金) 奈米粒子於薄膜表面增加吸附反應以增強感測能力。最後會嘗試將三種不同的氣體感測器整合到同一顆元件上形成一個智慧型雙型態氣體感測陣列。感測器的薄膜均使用射頻磁控濺鍍沉積ITZO材料，奈米金屬顆粒以真空熱蒸鍍法製作，並使用快速熱退火系統進行特性改良。針對不同的氣體感測器由以下簡短進行說明。
在第二章中，薄膜表面的鈀(Pd)奈米粒子對於氫氣有良好的催化反應且奈米顆粒大幅的提高元件表面與氣體的接觸面積，大幅地提高了對於氫氣的感測效率，在最佳溫度225℃下對於1% 的氫氣反應出 64845 的感測倍率，具有142秒響應時間以及6秒的回復時間，最低可以檢測到1 ppm 的氫氣說明了其具備較低的感測極限。
在第三章節中，薄膜表面的鉑(Pt)奈米粒子對於氨氣及氫氣有良好的催化反應且奈米顆粒大幅的提高元件表面與氣體的接觸面積，大幅地提高了對於氨氣的感測效率，在最佳溫度275℃下對於1000 ppm的氨氣反應出 1531 的感測倍率，具有極佳的92秒響應時間以及9秒的回復時間，且在最低檢測濃度30 ppb的氨氣仍具有2.14的感測倍率說明了其具備極低極限的感測能力。
在第四章節中，薄膜表面的金(Au)奈米粒子對於甲醛與酒精有良好的催化反應且奈米顆粒大幅的提高元件表面與氣體的接觸面積，大幅地提高了對於甲醛和酒精的感測效率，在最佳溫度275℃下對於20 ppm的甲醛反應出441的感應倍率，具有良好55秒響應時間以及25秒的回復時間，且在最低檢測濃度50 ppb的甲醛仍具有1.05的感測倍率。
在第五章，將上述三個章節的元件以重新設計過的光罩定義指叉電極圖形整合成一個同時可以量測氫氣、氨氣、酒精的三型態氣體感測器。
在上述元件中皆有著感測能力表現良好的氣體感測器，並具有多項元件優勢：體積小、低製作難度、低製造成本、低反應時間、高感測倍率。

This studied reports the fabrication and characterization of semiconductor‐based gas sensors targeting common volatile organic compounds (VOCs) –hydrogen, ammonia, formaldehyde, and ethanol. Indium tin zinc oxide (ITZO) thin films were deposited by RF magnetron sputtering, with an Ag nanoparticle underlayer to increase effective surface area and catalytic Pd, Pt, or Au nanoparticles atop to enhance adsorption reactions. Sensor performance was evaluated via rapid thermal annealing–modified devices, and an integrated dual‐mode sensor array combining three distinct sensing elements was demonstrated. Detailed sensing experiments and data analyses confirm the enhanced sensitivity and selectivity of the proposed devices.
In Chapter 2, palladium (Pd) nanoparticles on the film surface exhibit excellent catalytic reactions to hydrogen (H2) and significantly increase the surface area of the device in contact with the gas, greatly enhancing the sensing efficiency for H2. Experimentally, sensing response of 64845 was achieved under 1% H2/air gas at 225°C, with a response (recovery) time of 142 s (6 s). The sensor could detect H2 as low as 1 ppm, indicating its low detection limit.
In Chapter 3, the platinum (Pt) nanoparticles on the surface of the film exhibit excellent catalytic reaction towards both ammonia (NH3) and hydrogen (H2), significantly increasing the contact area between the device surface and the gas. This greatly enhances the sensing efficiency for NH3. Experimentally, the sensing response of 1531 was achieved under 1000 ppm NH3/air gas at 275°C, with a response time of 92 s and a recovery time of 9 s. Moreover, even at the lowest detectable concentration of 30 ppb NH3, it still maintains a sensing response of 2.14, demonstrating its extremely low detection limit capability.
In Chapter 4, gold (Au) nanoparticles on the surface of the thin film exhibited good catalytic activity towards both formaldehyde (HCHO) and ethanol (C2H5OH), significantly increased the contact area between the device surface and the gas, leading to a notable improvement in formaldehyde and ethanol sensing efficiency. Experimentally, sensing response of 441 was achieved under 20 ppm HCHO/air gas at 275°C, with a response (recovery) time of 53 s (25 s). Moreover, even at the lowest detectable concentration of 50 ppb NH3, it still maintains a sensing response of 3.13, demonstrating its extremely low detection limit capability.
In Chapter 5, the devices from the aforementioned three chapters are integrated into a single three-mode gas sensor capable of measuring both hydrogen, ammonia, and ethanol gases.
Through redesigning the photomask, the defined interdigitated electrode patterns of the sensors are combined. Each of the mentioned devices exhibits excellent sensing capabilities and possesses several advantages: small size, low fabrication complexity, low manufacturing cost, low response time, and high sensitivity.

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