本文利用射頻磁控濺鍍系統去沈積氧化銦鎵薄膜當作感測層，透過不同的銦摻雜和不同的通氧量去探討對薄膜的影響，然後將其應用在紫外光感測器和乙醇氣體感測器。
首先，我們以共靶與單靶的方式去沈積氧化銦鎵薄膜，為了探討不同銦摻雜和不同通氧量對薄膜的影響，穿透被用來分析薄膜的光學特性，AFM，EDS，以及XPS被用來分析薄膜的物理及化學特性。由穿透分析得知銦摻雜越多，能帶就越小，導電性也會增加。由AFM得知通氧量越多粗糙度數值越低，薄膜表面越平滑品質更好。由EDS得知氧化銦靶材功率提高，銦鎵比提高，銦的摻雜變多。由XPS得知銦摻雜變多的時候氧空缺變多，通氧量變多的時候氧空缺變少。
接著製備共靶式的氧化銦鎵紫外光感測器，氧化鎵的靶材功率固定在80W，調變氧化銦的靶材功率分別為20W，30W，40W，以及80W。純氧化鎵的暗電流過小不易量測，純氧化銦及80W/80W的暗電流都過大超過機台的量測範圍(100mA)。經過一系列的測量得知，當摻雜銦變多的時候1.暗電流會上升、2.靈敏度上升，在30W/80W的時候達到最大值5.20x103、3.光響應也上升，在40W/80W的時候達到最大值1.72x102 A/W、4.響應恢復時間則會上升。過多的銦摻雜則會造成1.暗電流過大、2.靈敏度下降、3.響應恢復時間下降。
接著製備共靶式的氧化銦鎵乙醇氣體感測器，氧化鎵的靶材功率固定在80W，調變氧化銦的靶材功率分別為40W，60W，以及80W。所有元件的響應都隨著溫度提高而上升，達到最佳溫度然後下降。當銦摻雜變多的時候1.阻值變小、2.響應變大，在60W/80W 300℃下量側達到最大值80.6%。當銦摻雜過多的時候，電流過大響應變小。響應恢復時間在最佳參數60W/80W 300℃量側下為8s/28s。
最後由於單靶比共靶有著更簡單的製程及更好的穩定性，我們也製備了單靶式的氧化銦鎵乙醇氣體感測器。使用IGO (4:6)及IGO (6:4)，分別在通氧量0%，4%，及10%的環境下製備。IGO (4:6)的元件由於鎵摻雜太多，阻值過大，不能量到完整的數據，所以後來也量測銦摻雜較多的IGO (6:4)。IGO (6:4)所有元件的響應也都隨著溫度提高而上升，達到最佳溫度然後下降。響應也隨著通氧量變多而上升，在10% 260℃的量測下達到最大值89.2%，響應恢復時間在最佳參數下也有7s/44s。兩種最佳參數元件也有好的重複性及氣體選擇性。

In this study, an RF magnetron sputtering system was used to deposit indium gallium oxide (IGO) thin films as the sensing layer. The influence of different indium doping and oxygen flow rates on the film properties was investigated. Subsequently, the IGO thin films were applied in ultraviolet (UV) photodetectors and ethanol gas sensors.
First, we deposited indium gallium oxide (IGO) thin films using both co-sputtering and single-target methods. To investigate the effects of different indium doping levels and oxygen flow rates on the films, various analytical techniques were employed. Transmittance analysis was conducted to study the optical properties of the films, while AFM (Atomic Force Microscopy), EDS (Energy-Dispersive X-ray Spectroscopy), and XPS (X-ray Photoelectron Spectroscopy) were used to analyze the physical and chemical characteristics of the films.
Transmittance analysis revealed that increasing indium doping led to a decrease in the bandgap and an increase in conductivity. AFM analysis showed that higher oxygen flow rates resulted in lower roughness values, indicating smoother and higher-quality film surfaces. EDS analysis indicated that increasing the power of the indium oxide target resulted in a higher indium-to-gallium ratio, leading to higher indium doping. XPS analysis revealed that higher indium doping led to an increase in oxygen vacancies, while higher oxygen flow rates resulted in a decrease in oxygen vacancies.
Next, we fabricated co-sputtered indium gallium oxide (IGO) ultraviolet (UV) photodetectors. The power of the gallium oxide target was fixed at 80W, while the power of the indium oxide target was varied at 20W, 30W, 40W, and 80W. The dark current of pure gallium oxide was too low to measure accurately, while pure indium oxide and 80W/80W exhibited dark currents exceeding the measurement range of the equipment (100mA). Through a series of measurements, the following observations were made: As the indium doping increased: 1. the dark current increased. 2. The sensitivity of the photodetector increased, reaching its maximum value of 5.20x103 at 30W/80W. 3. The responsivity increased, peaking at 1.72x102 A/W at 40W/80W. 4. The response recovery time increased. Excessive indium doping resulted in the following effects: 1. The dark current became excessively high. 2. The sensitivity decreased. 3. The response recovery time decreased.
Next, co-sputtered indium gallium oxide (IGO) ethanol gas sensors were fabricated, with the power of the gallium oxide target fixed at 80W and the power of the indium oxide target varied at 40W, 60W, and 80W. The response of all devices increased with increasing temperature, reaching an optimum temperature, and then decreasing. When the indium doping increased, the following effects were observed: 1. The resistance decreased. 2. The response increased, reaching its maximum value of 80.6% at 60W/80W and 300°C. However, when the indium doping exceeded a certain level, the current became too high, resulting in a decrease in the response. The response recovery time for the optimal parameters of 60W/80W and 300°C was 8s/28s.
Finally, to simplify the fabrication process and improve stability, we also prepared single-target indium gallium oxide (IGO) ethanol gas sensors. Two targets, IGO (4:6) and IGO (6:4), were prepared under different oxygen flow rates of 0%, 4%, and 10%. However, the IGO (4:6) devices, due to excessive gallium doping, had high resistance and incomplete data acquisition. Therefore, the measurements were focused on the IGO (6:4) devices with higher indium doping. For the IGO (6:4) devices, the response increased with increasing temperature, reached an optimum temperature, and then decreased. Additionally, the response increased with higher oxygen flow rates, reaching its maximum value of 89.2% at 10% oxygen flow rate and 260°C. The response recovery time for the optimal parameters was 7s/44s. Both sets of optimal parameter devices exhibited good repeatability and gas selectivity.

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