本論文旨在研究純氧化鎢薄膜及摻雜之氧化鎢薄膜的結構、成分及價態，以及針對其應用在氣體感測器之探討。首先，針對不同退火溫度退火持溫之純氧化鎢薄膜作比較，再進而討論鐵、矽及碳不同含量的摻雜對氧化鎢薄膜的結構及氣體感測性質之影響。本研究以射頻磁控濺鍍法，在室溫下直接沉積金屬鎢薄膜於基板上，再於大氣中退火持溫成長為氧化鎢薄膜，並藉由XRD、SEM、EDS及XPS等各項物性及化性分析儀器觀察所製備之氧化鎢薄膜，並利用本實驗室自組裝之氣體感測裝置，針對CO、CO2、甲醇及乙醇四種目標氣體作氣體感測分析。
實驗結果為550˚C退火持溫之純氧化鎢薄膜在工作溫度350˚C下對四種目標氣體進行氣體感測有最高敏感度，且藉由SEM觀察表面形貌發現，相較其他較高退火溫度而言，其表面團簇物或晶粒大小較小；就摻雜之氧化鎢薄膜而言，一定含量的矽摻雜及碳摻雜之氧化鎢薄膜，對四種氣體進行氣體感測，其結果顯示，矽及碳摻雜有抑制CO及CO2敏感度，提高甲醇及乙醇敏感度之效果，且藉由SEM觀察碳摻雜之氧化鎢表面形貌發現，碳的摻雜使氧化鎢形成類似微球的結構；然而鐵的摻雜則是抑制了四種氣體的敏感度，從SEM觀察表面形貌則是發現，鐵的摻雜使氧化鎢從顆粒狀轉變成為條狀。

This thesis is concerned with the thin film growth and characterization of Fe, Si and C doped tungsten oxide (WO3-x) for gas sensing applications. The films were grown by RF magnetron sputter deposition in pure Ar atmosphere at room temperature, followed by post-deposition annealing in air at 550 ~ 750 C. The composition and microstructure of the grown films, as well as the valence state of tungsten ions, were studied by XRD, SEM, EDS and XPS. The electric resistances of the films in pure air (Ra) and in the air containing 5 ppm each of the gases of CO, CO2, methanol and ethanol (Rg) were tested, according to which the gas sensitivity (S) was defined as, S=Ra/Rg. The effects of film composition, microstructure and dopant on the gas sensitivity and the response and recovery times were discussed. The results showed that at the working of 350 C, the 35.0 % C doped WO3-x films had the best sensitivity for alcohols, i.e. S=5.89 and 5.42 for ethanol and methanol, respectively, compared to S=1.71 and 1.19 for CO and CO2, respectively. The response/recovery times of the 35.0 % C doped WO3-x films were 7/244 s and 8/463 s for ethanol and methanol, respectively.

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