最理想化的六角形陣列之奈米碳管束使用熱化學氣相沉積法合成，為了增強奈米碳管的電子場發射特性，針形狀的二氧化釕與錐形狀的氧化鋅奈米結構分別使用金屬有機化學氣相沉積法與熱化學氣相沉積法成長於奈米碳管的表面。經由穿透式電子顯微鏡影像觀察得知，針形狀的二氧化釕與錐形狀的氧化鋅奈米結構皆均勻的成長於奈米碳管表面。而奈米碳管是作為成長二氧化釕與氧化鋅奈米結構的附著支架。二氧化釕、氧化鋅奈米結構成長於奈米碳管束與原始的奈米碳管束的電子場發射效應皆會被測量。研究結果顯示針狀的二氧化釕與錐狀的氧化鋅奈米結構皆會增強奈米碳管的電子場發射特性，因為此兩種金屬氧化物奈米結構成長於奈米碳管表面可以增加其電子場放射源，而每個針形狀的二氧化釕與錐形狀的氧化鋅奈米結構也皆可以作為獨立的場發射源。其結果證實二氧化釕與氧化鋅奈米結構成長於奈米碳管為具有發展潛力的場發射材料。

The optimal carbon nanotube (CNT) bundle array with a hexagonal arrangement was synthesized using thermal chemical vapor deposition (CVD). To enhance the electron field emission characteristics of the CNTs, needle-like ruthenium dioxide (RuO2) nanostructures were grown onto vertically aligned CNT bundles using metal organic chemical vapor deposition (MOCVD) and tapered zinc oxide (ZnO) nanostructures were grown on vertically aligned CNT bundles using another thermal CVD technique. Transmission electron microscopy (TEM) images showed that the RuO2 and ZnO nanostructures were grown onto the CNT surface uniformly. The CNTs were the principal part and template, with the needle-like RuO2 and tapered ZnO nanostructures grown outwardly from the CNTs. The electron field emissions of pristine CNT bundles, RuO2-coated CNT bundles, and ZnO-coated CNTs were measured. The results showed that both the RuO2 and ZnO nanostructures grown onto the CNTs could improve the electron field emission characteristics. This was because the nanostructures of both the metal oxides grown onto the CNT surface could increase the emission sites, and each needle-like RuO2 or tapered ZnO nanostructure could be regarded as an individual field emission site. These results demonstrated that ZnO-coated CNTs and RuO2-coated CNTs are promising field emitter materials.

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