基板效應對二元催化劑成長奈米螺旋碳管之影響

Substrate Effect on the Morphology of As-grown Carbon Nanocoils

謝燿聯(Yao-Lien Hsieh)

指導教授 ： 張所鋐

國立臺灣大學/工學院/機械工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.02160

摘要

本論文針對基板效應對於成長奈米螺旋碳管的影響作探討，提出了一個成長『臨界厚度』的概念，利用二元素溶液式催化劑濃度的改變，在二氧化矽、矽晶元、金、鈦等基板上，成功的成長出奈米螺旋碳管，並分析在不同濃度下與不同基板上所成長螺旋碳管之特徵尺寸的差異及尺寸分佈狀況。
實驗上以化學氣相沈積法來成長奈米螺旋碳管，成長壓力為1大氣壓，成長溫度為700℃，成長時間為15分鐘，並通入反應氣體乙炔：氬氣為5：650 sccm；螺旋碳管的成長結果以掃瞄式電子顯微鏡作檢驗，同時統計其線徑、外徑、螺距等3項特徵尺寸，並分析催化劑濃度對碳管尺寸的影響，以及基板效應對碳管尺寸的影響。
實驗結果可以成功的控制螺旋碳管的線徑在20 nm∼350 nm，外徑在100 nm∼1500 nm，螺距在100 nm∼1300 nm之間；同時發現在不同的成長基板上，螺旋碳管會有不同的幾何尺寸，並且使用濃度高的催化劑，可以得到尺寸大且分佈廣的螺旋碳管，使用濃度稀的催化劑，可以成長出尺寸小且分佈集中的奈米螺旋碳管。

關鍵字

奈米碳管 ； 螺旋線圈 ； 化學氣相沈積法 ； 基板效應 ； 尺寸控制

並列摘要

In this study, we focus on the substrate effect of the carbon nanocoils, who bring up an idea about “growing critical thickness of the catalyst”. We can grow carbon nanocoils on SiO2、Si、Au、Ti successfully by adjusting the concentration of carboxylic acid metals in the solution. Another part of this study is to do statistics and to analyze the characteristic diameters’ variation and distribution of carbon nanocoils.
Carbon nanocoils have been synthesized by chemical vapor deposition, which are obtained by 2 metals-catalyzed pyrolysis of acetylene at 700℃, under 1 atm. The growing results have been observed by SEM. Coils’ line diameter、coil diameter and pitch are the main characteristic diameters which we concern about. One part of the discussion is between the concentration of catalyst and diameter, while another part is between the substrate effect and diameter.
In summary, carbon nanocoils with controlled diameters have line diameter：20 nm∼350 nm, coil diameter：100 nm∼1500 nm, and pitch：100 nm∼1300 nm. There are different morphologies of as-grown carbon nanocoils from substrate to substrate. By using high concentration of catalyst, we can produce large size and wide distribution. On the other hand, by using low concentration of catalyst, we can produce small size and limited distribution.

並列關鍵字

Carbon nanocoil ； CNT ； Chemical Vapor Deposition ； Substrate Effect ； Diameter Control

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