本研究利用了水熱法在玻璃基板成長氧化鋅奈米線陣列，再使用磁控濺鍍製程沉積鐵酸鉍薄膜，進行兩者靈敏度比較。首先比較不同厚度之氧化鋅種晶層，並探討種晶層對奈米線表現形貌的關係，研究結果發現，隨著種晶層的厚度增加，表面粗糙度會降低，其奈米線的線徑與線長都會降低。再對丙酮與氨水兩種氣體進行氣體感測實驗，然後使用表面改質製程，採用了低溫濺鍍製程沉積鐵酸鉍(BiFeO)薄膜披覆氧化鋅奈米線上增加其感測靈敏度。再利用水熱法成長厚度27、35、42 nm的種晶層之氧化鋅奈米線，並在操作溫度100°C、150°C與200°C下進行丙酮與氨水氣體感測，研究結果顯示，種晶層厚度35 nm所成長的氧化鋅奈米線具有最佳的感測靈敏度(丙酮氣體S =7.2 和氨水氣體S= 3.72) ；接著比較鐵酸鉍薄膜披覆於氧化鋅奈米線與純氧化鋅奈米線兩者的氣體感測靈敏度，結果顯示，有鐵酸鉍薄膜之氧化鋅奈米線感測靈敏度有上升的趨勢(丙酮氣體S =7.41 和氨水氣體S= 4.61)，且氨水氣體的感測靈敏度有隨著操作溫度的上升而增加的趨勢，最後對氨水進行高溫(300°C)與室溫(25°C)之氣體感測，研究結果指出感測響應速度與氨水濃度成正比的關係，尤其是鐵酸鉍薄膜披覆氧化鋅奈米線感測器，其濃度越高，感測響應就越明顯，即使在低濃度(1 ppm)下也有這個結果。

In this study, the ZnO nanowires are prepared on glass substrate by using hydrothermal method, and deposited BiFeO thin film on the ZnO nanowires by sputtering; later, comparing the sensitivity of the pure ZnO nanowires and the ZnO nanowires with BiFeO. Different thickness of ZnO seed layer can be obtained by changing the sputtering deposition power, so with the increase of the thickness of seed layer, the surface roughness is reduced, and its nanowires diameter and length will be reduced. Using a hydrothermal method prepares ZnO nanowires of three kind of thickness 27, 35 and, 45 nm, and conducts gas sensing experiment of acetone and ammonia at 100, 150 and 200 °C, respectively. The seed layer thickness of 35 nm grown ZnO nanowires have the best sensing sensitivity (S = 7.2 for acetone, S = 3.72 for ammonia). After that we adopt the surface modification process to deposit the bismuth ferrites thin film coated on ZnO nanowires to increase gas sensitivity, and we find that the BiFeO thin film on ZnO nanowires of sensing sensitivity has been improved (S = 7.41 for acetone, S = 4.61 for ammonia), and ammonia sensing sensitivity are increased when operating temperature increases. Finally, conduct gas sensing experiment of high-temperature (300 °C) and room temperature (25 °C) ammonia, and the response speed is proportional to the concentrations of ammonia, especially BiFeO thin film coated on ZnO nanowires, With the concentrations increase, the response is also increase, even at low concentrations (1 ppm) also have the same result.

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