利用化學氣相沉積法以氣相－固相成長機制合成一維氧化鋅奈米結構時，如：奈米線、奈米尖錐或奈米柱，大多是利用活性低的貴金屬做為催化劑，如：金、鉑和銀，而本論文主要是利用活性較高的鎢金屬薄膜做為催化劑；在實驗中可發現利用鎢金屬薄膜做為催化劑550°C的溫度下進行化學氣相沉積法合成氧化鋅奈米柱時，由於鎢本身容易與成長環境中的反應氣體產生化學反應，因此實驗發現成長完成之後的氧化鋅奈米柱在其底部存在氧化鋅鎢的複合結構，而從拉曼光譜以及X光繞射圖形也可以驗證出氧化鋅鎢結構的存在，因此藉由鎢催化劑薄膜可成長出氧化鋅/氧化鋅鎢複合奈米柱。
　　從光激發螢光光譜中可觀察到氧化鋅/氧化鋅鎢複合奈米柱的螢光峰值相對於氧化鋅奈米柱的螢光峰值有藍移的現象，除此之外，氧化鋅/氧化鋅鎢複合奈米柱的電子場發射特性之起始電場亦從單純只有氧化鋅奈米柱的3.95V/μm下降至3.55 V/μm，而增強因子為1839，相對氧化鋅奈米柱的1499也有明顯的提升。
　　最後本實驗以10比1的比例混合氮氣與氧氣對氧化鋅/氧化鋅鎢複合奈米柱分別進行300°C、400°C 以及500°C的熱退火處理，從實驗結果可發現當熱退火溫度為400°C時可以有效使氧化鋅/氧化鋅鎢複合奈米柱電子場發射特性之起始電場與截止電場分別降低至3.05V/μm與4.05V/μm，增強因子也上升至2342。
　　根據以上論述做出以下結論，本實驗主要是藉由鎢金屬催化薄膜得到了氧化鋅鎢複合結構，而得到氧化鋅/氧化鋅鎢複合奈米柱，並在合成複合奈米柱之後再利用400°C的條件進行熱退火處理，藉由這兩種方法皆可以提升氧化鋅奈米柱之電子場發射特性。

Synthesis of one-dimensional (1-D) zinc oxide nanostructures (ZnO) based on vapor-solid (V-S) mechanism by chemical vapor deposition (CVD) method usually utilize low active metal catalysts, such us gold (Au), platinum (Pt) and silver (Ag). In this work, the researcher utilizes tungsten thin film as the catalyst, the experiment reveals the synthesis of ZnO nanorods by chemical vapor deposition method at 550 °C which discovered the zinc tungstate nanostructures (ZnWO4) under ZnO nanorods by Raman spectrum and XRD patterns due to the tungsten catalyst were easily reactive with other gases in the furnace of the chemical vapor deposition system. Thus, ZnO/ZnWO4 composite nanorods were been synthesized by tungsten catalyst. Furthermore, the photoluminescence spectrum (PL) indicates the UV emission of ZnO/ZnWO4 composite nanorods possess the blue shift phenomenon compared to the pure ZnO nanorods. In addition, the field emission properties of ZnO/ZnWO4 composite nanorods includes a turn-on field (Eon) of 3.55 V/μm and a enhancement factor (β) of 1839, both better than found in ZnO nanorods without ZnWO4 nanostructures.
Finally, the research mixed nitrogen and oxygen with the ratio of 10:1 to annealing ZnO/ZnWO4 composite nanorods at 300 °C, 400 °C and 500 °C, respectively. The result shows the best temperature was 400 °C to enhance the field emission properties of ZnO/ZnWO4 composite nanorods. The field emission properties of the annealing ZnO/ZnWO4 composite nanorods at 400 °C includes a turn-on field of 3.05 V/μm, a threshold field (Eth) of 4.05 V/μm and a enhancement factor of 2342, both better than found in as-grown ZnO/ZnWO4 composite nanorods.

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