奈米碳管由於其高長徑比、低功函數等特性，被視為是下一世代場發射顯示器之理想材料。然而，要達到實際量產的程度，仍有許多問題需要克服，例如：穩定性、均勻性等。本實驗討論了兩種改善奈米碳管場發射特性的方法，分別是尋找最佳的奈米碳管柱陣列與披覆金屬氧化物二氧化釕。這兩種方式分別有助於減少屏蔽效應與延長場發射壽命。由實驗結果我們得到，當奈米碳管柱高度為間距的一半時，有最佳場發射特性，我們將原因歸咎於，以此方式排列之奈米碳管柱陣列的密度與屏蔽效應達到最佳的平衡點。然而，當奈米碳管柱高度為間距的三分之一時，有較為穩定的場發射電流，我們將原因歸咎於，其單位面積的碳管柱受熱較少，於是降低了奈米碳管劣化的機會。在披覆二氧化釕的實驗方面，實驗結果成功的將垂直成長於矽基板上之奈米碳管薄膜，以有機金屬氧化物化學氣相沉積法披覆一層金屬氧化物二氧化釕，利用二氧化釕的金屬氧化物性質，增強奈米碳管於場發射方面的特性，不僅改善奈米碳管在場發射上之耐久性與穩定性，並且有效降低起始電場與臨界電場。

Carbon nanotubes (CNTs) are promising candidates for cold cathode electron field emitters in the next generation of field emission displays (FED). Some critical properties such as emission current density, stability and uniformity should be guaranteed before they can become commercial products. In order to construct a useful device, this study discusses two methods to modify the field emission performance. One is to set up an optimum arrangement of carbon nanotube arrays, and the other is to coat RuO2 on CNTs. These two methods could reduce the screening effect and elongate the lifetime of CNT based emitters, respectively. The optimum inter-bundle distance was found to be twice their height: the possible cause being that the number density of bundles compared to the screening effect generated a greater effect on field emission. However, a relatively stable emission current was measured from the samples whose inter-bundle distance was triple their height. It is assumed that the reason for this is that the bundles suffered less Joule heating per unit area during the measurement. Moreover, the process of covering the tips of CNTs with a thin film of RuO2 eventually obtained the best matching of these two elements. The study not only enhanced the field emission performance of CNTs, but also extended field emission lifetime by applying a thin film of RuO2 on the CNT tips.

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