使用[(CH3CH2)C5H4]2Ru當前驅物，於冷壁式有機金屬化學氣相沉積系統中成長二氧化釕奈米結構，其沉積在不同平面之基板上有不同的成長方向。使用場發射掃描式電子顯微鏡、X光繞射譜線，對二氧化釕奈米結構做結構的分析。從FESEM照片觀察在不同的基板上，其奈米柱有垂直、傾斜的成長形式。此外，探討二氧化釕奈米結構之場發射特性，包括不同長度、不同形貌和不同密度。對不同長度這個因素而言，我們利用四種不同長度的奈米柱(不同長度的奈米柱，其形貌和密度差不多)做場發射的量測，得到的結果是：當奈米柱長度為1.5μm時，其驅動電壓(Ethr)、啟動電壓(Eto)最低及 值(場發射加強常數)最高。我們認為是其高寬比(aspect ratio)最高的原因。對不同形貌而言，我們也利用四種不同形貌的奈米結構做場發射的量測，得到的結果是：形貌為奈米線時，其驅動電壓(Ethr)、啟動電壓(Eto)最低及 值(場發射加強常數)最高。我們歸究其原因在於其奈米線的尺寸較小，造成其局部分佈電場在尖端比其他形貌強，所以場發效果較好，最後，我們也利用MOCVD 成功成長三種不同密度的奈米線，我們也利用這三種不同密度的奈米線做場發射，我們也發現：高密度的奈米線其驅動電壓(Ethr)、啟動電壓(Eto)最高及 值(場發射加強常數)最低，因為高密度的奈米線代表著兩兩發射器的距離比較短，而兩兩發射器的距離比較短會互相影響其尖端的局部分佈電場，造成尖端的局部電場減弱，而有電子屏壁效應的效果。最後我們認為分析這些結果在使用RuO2奈米結構當場發元件是有價值的。

The self-assembled and well-aligned ruthenium dioxide (RuO2) nanostructures (NS), using [(CH3CH2)C5H4]2Ru as the precursor, have been grown on various substrates with different orientations via the technique of cold-wall metalorganic chemical vapor deposition (MOCVD). The conditions for the one-dimensional growth of RuO2 NS, including nanorods (NRs), nanotubes (NTs), nanowires (NWs), and nanotips are studied and the probable mechanisms of the formation of 1-D NS are discussed.
The surface morphology and structure of the as-grown NS were characterized using field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD). XRD patterns and FESEM images show vertical or tilted alignment of NS on various substrates. In addition, we also have studied the field-emission (FE) properties of the RuO2 NS with different length, morphology and density. It was found that the length of the RuO2 NS has considerable effect on their FE properties, especially the turn-on field (Eto), threshold field (Ethr) and field-enhancement factor ( ). Among four different lengths (similar morphology and density), the NRs with l=1.5μm have the lowest Eto and Ethr and largest field-enhancement factor ( ). The superior performance is attributed to the highest aspect ratio. Among different morphologies, the RuO2 NWs having a lowest Eto and Ethr and the larger field-enhancement factor ( ) can be due to the small emitter radius of the NS. High NW density remarkably reduces the local field at the emitters owing to the screening effect, which is related to the density of the emitters. The analysis results could be valuable for the application of field-emission-based devices using RuO2 nanostructures as cathode materials.

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