本實驗利用E-beam電子束直寫系統在六吋矽晶圓上定義各種不同間距之奈米柱，隨後經過顯影及蝕刻等技術，製作出不同間距的柱子，並利用掃描式電子顯微鏡觀察其樣貌。在確定其間距無誤後，以真空電性量測系統測量其場發射性質。根據實驗結果發現，柱子在不同間距下之場發射性質隨著間距越大，其場發射性質會漸漸提升，但是過密之柱子，場發射電之電流密度相對之下，過於微小，之後利用高密度電漿化學氣相沉積系統在低溫下介由通入氫氣、氬氣等，使氫電漿均勻蝕刻在六吋矽晶圓不同的間距的柱子上使其成為奈米草結構，目的是使不同間距柱子能夠更佳的銳化，同樣的經過真空電性量測系統之測量，我們發現，在蝕刻奈米草結構之後，對於此雙層結構之場發射性質的改善並不顯著，且其效果還未達到單純奈米碳管之場發射能力，我們更進一步要在此雙層結構上成長奈米碳管，首先利用F13TCS, E-gun電子束蒸鍍7 nm Ni, 以及CHF3電漿等處理，以酒精為碳源成長奈米碳管，經過掃描式電子顯微鏡觀察，我們發現，以金屬鎳成長奈米碳管之方式能夠使碳管均勻分佈在奈米草之表面，對進一步的場發射量測來說較不容易造成誤差。我們以此為基板，利用熱化學氣相沉積系統在不同間距之間距奈米柱上生長奈米碳管，觀察不同結構之場發射特性。 我們發現製造出不同間距之碳管生長於間距奈米柱蝕刻奈米草之後，整體結構之場發射能力，比奈米碳管還要好，而我們所創造之一系列結構亦符合F-N方程式，顯示其發射電流是由場發射機制所致。 Leica E-beam lithography and etching were used to create nanopillars array with different spaces from 2 ?m to 100 ?m. We used scanning electronic microscope to observe the morphology of the pillars and check the distance between the pillars. We measured the field emission characteristic and found that the field emission had lower turn-on field with increasing distance. Comparing to other samples with different distance, we found that 2 ?m pillar had the lowest current density. We also observed that the nanopillars did not exceed carbon nanotubes in the field emission performance. To improve the field emission performance, we used high density plasma chemical vapor deposition system to create another nanostructure on nanopillar. RF power was used to generate hydrogen and argon plasma to evenly etch the nanopillar on 6 inch wafer. Through this process, we got nanograss, which may be the smallest silicon nanostructure in the world. This two-tier nanograss-on-nanopillar structure had better characteristic of field emission than nanopillar array, but still not exceeded carbon nanotubes. Finally we tried to grow carbon nanotubes on top of this two-tier nanostructure. We adopted three methods to grow carbon nanotubes on nanograss, which were F13TCS evaporation, 7 nm nickel coating, and CHF3 plasma treatment. The scanning electronic microscope showed that only the sputtering methods would lead to uniform carbon nanotubes on the nanograss, so we chose the sputtering as the growing methods for catalyst layer. After we grew carbon nanotubes on the two-tier nanostructures, we found that their field emission characteristic exceeded carbon nanotube successfully. F-N plot of all the structure shows that the measured current originated from the tunneling mechanism.
