電致色變材料是近年來被廣泛研究的一種新興能源材料，它可以被應用在汽車和建築物之視窗玻璃上，以製作節省能源、調節光線及控制熱負荷之智慧型窗戶及液晶平面顯示器上。本實驗利用射頻磁控濺鍍法沉積氧化鉬薄膜，並探討各種濺鍍條件對薄膜成份、微結構、和電致色變性質的影響。
實驗結果發現，隨著氧氣分率的增加，薄膜中的氧含量會隨之增加，使薄膜容易形成高化學計量比的α相結構；在高氧氣分率下沉積氧化鉬薄膜，薄膜具有較佳的可逆性，當氧氣分率為80% 時，在波長550nm 處，其著色去色之穿透率變化為35.50%，且具有較高的光學密度， 而薄膜之著色效率CE=23.81cm2/C。
當以不同基板溫度沉積氧化鉬薄膜時，發現當基板溫度到達250℃時，薄膜即會開始結晶化，且隨著基板溫度從室溫增加到350℃時，氧化鉬薄膜的光能隙會從2.82eV 上升至3.07eV，這是因為基板提供足夠能量使氧化鉬薄膜堆積成具開放性通道的α相結構。當基板溫度在350℃時，薄膜具有最大的著色去色之穿透率變化為35.50%以及薄膜之著色效率CE=23.81cm2/C。

Electrochromisms had been widely investigated as a new energy harvesting material due to its potential applications for smart window of architecture, automobile glazing to save energy, modulate the transmission of light and solar radiation and also liquid crystal displays. Therefore, the object of this study was focused on the effects of sputtering conditions on the composition, microstructure and electrochromic properties of molybdenum trioxide films prepared by r.f. magnetron sputtering.
Experimental results indicated that with increasing oxygen partial pressures, oxygen content of the films was increased which was tend to form α-MoO3 phase structure with higher stoichiometry. The films deposited at oxygen partial pressure of 80% showed the best electrochromic reversibility, and the transmission change betweencolored and bleached states at a wavelength of 550nm was 35.50%. Also, the film exhibited higher optical density, and coloration efficiency was 23.81cm2/C.
Then the molybdenum trioxide films were deposited under varied substrate temperature. It was also found that the crystallinity of films was obtained when the substrate temperature reached 250℃. As the substrate temperature increasing from room temperature to 350℃, the optical band
gap increased from 2.82 to 3.07eV due to the formation of α-MoO3 structure with opening tunnel driven by the thermal energy acquired from the heating of the substrate. When the substrate temperature was 350℃, the films showed the best transmission change between colored andbleached states at a wavelength of 550nm was 35.50% and coloration efficiency was 23.81cm2/C.

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