本研究利用複合奈米結構提升三氧化鎢奈米柱一氧化氮氣體感測器特性，其目的為應用於醫療檢測呼氣一氧化氮濃度(Fraction of exhaled nitric oxide, FeNO)，以三氧化鎢奈米柱作為基礎，將透過兩種不同的奈米結構對一氧化氮氣體感測器之響應特性進行優化。第一部分為微圖案化結構之晶種層，透過旋塗奈米球的方式製作奈米球模板，以最佳旋塗參數，利用氧電漿蝕刻奈米球改變微圖案化結構尺寸，並於其上沉積二氧化矽後，再將奈米求去除，接續沉積三氧化鎢完成為微圖案化晶種層，使用此微圖案化晶種層的目的是使三氧化鎢奈米柱於水熱法成長時產生交疊，形成更多同質接面以提升氣體響應度。以第一段轉速500 rpm旋轉60秒及第二段轉速1250 rpm旋轉10秒旋塗直徑為800 nm之奈米球，並於45 oC烘烤5分鐘，可形成緊密且單層之奈米球模板，在氧電漿蝕刻時間為6分鐘之奈米球模板所製備出的微圖案化結構使三氧化鎢奈米柱具有最多交疊，最佳微圖案化三氧化鎢奈米柱一氧化氮氣體感測器於操作溫度為140 oC，一氧化氮氣體濃度為1 ppm時，相較於平面式晶種層之氣體響應度可從2297.3%提升至6249.4%。
第二部分為沉積p型金屬氧化物奈米顆粒於n型三氧化鎢奈米柱表面形成異質接面，沉積不同材料之p型金屬氧化物奈米顆粒及沉積不同含量p型金屬氧化物奈米顆粒皆會影響氣體響應特性，利用穿透式電子顯微鏡觀察奈米顆粒尺寸大小並利用能量散射光譜儀分析其含量，當沉積鎳含量為0.83 at.%之氧化鎳奈米顆粒修飾於微圖案化三氧化鎢奈米柱氣體感測器時，在一氧化氮氣體濃度為1 ppm的環境下，其最佳操作溫度為127.5 oC，且響應度可達到7183.6%，響應時間為49秒，回復時間為92秒。
最後於穩定性的測試中，通入濃度為1 ppm之一氧化氮氣體，操作溫度為127.5 oC，在相對濕度(Relative humidity, RH)由50%提升至90%的條件下，其氣體響應特性僅減少8.1%；在一氧化氮氣體濃度為1 ppb環境下，響應度可達到48.8%；且在檢測不同氣體的量測下，其他氣體具有的最高響應度也只佔一氧化氮氣體響應度的8.8%。結果顯示，複合奈米結構三氧化鎢奈米柱一氧化氮氣體感測器除了能有效提升氣體響應度及靈敏度外，能於高濕度及低濃度的環境中保有響應特性及良好的氣體選擇性，滿足應用於醫療檢測呼氣一氧化氮的環境要求。

This study used the composite nanostructures to enhance the performance of nitric oxide (NO) gas sensors based on tungsten trioxide (WO₃) nanorods for medical applications in measuring the fraction of exhaled nitric oxide (FeNO). Using WO₃ nanorods as the foun-dation, the response characteristics of the NO gas sensor were optimized through two dis-tinct nanostructures. In the first part, the micro-patterned seed layer was created using a nanosphere template formed by spin-coating nanospheres with optimal spin-coating pa-rameters, oxygen plasma etching was employed to adjust the size of the micro-patterned structure. This micro-patterned seed layer caused the WO₃ nanorods to overlap during hydrothermal growth, forming more homojunctions, which could enhance the responsiv-ity of the gas sensors. The micro-patterned structure prepared with 6 minutes of oxygen plasma etching resulted in WO₃ nanorods with the highest amount of overlap. The opti-mal micro-patterned WO₃ nanorod NO gas sensors, operating at 140 °C and NO concen-tration of 1 ppm, compared to a WO₃ nanorod NO gas sensors with planar seed layer, the responsivity improved from 2297.3% to 6249.4%. In the second part, p-type metal oxide nanoparticles were deposited on the surface of n-type WO₃ nanorods to form heterojunc-tions. The gas response characteristics were influenced by the material and quantity of p-type metal oxide nanoparticles. When WO₃ nanorods were decorated with nickel oxide nanoparticles containing 0.83 at.% nickel, under a NO concentration of 1 ppm, the re-sponsivity of micro-patterned WO₃ nanorod NO gas sensors achieved to 7183.6% at op-timal operating temperature of 127.5°C, it exhibited a response time of 49 seconds, and a recovery time of 92 seconds.

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