利用介電泳組裝奈米碳管成束及其應用探討

本論文是以介電泳技術為基礎對奈米碳管進行集束組裝，並探討奈米碳管束的衍伸應用，奈米碳管在交流電場下會被電偶極化，並且於介電力的作用下會立即轉向於外加電場的方向，隨後朝向電場強度強的地方泳動，最後傾向於順著外加電場的方向進行排列，隨著溶液的蒸發，表面張力亦會形成束縛力對已轉向且平行於電場方向的奈米碳管進行捕捉，最終形成奈米碳管束。此外，本研究還利用混入奈米銀及在碳管束外層介電泳奈米銀層以增加奈米碳管束的導電性能，最後再以焦耳加熱退火處理，進一步的降低其電阻值，奈米碳管束混入奈米銀粒子，可以用於改善碳管與碳管接合處間的接觸電阻，並且用以填充碳管間多餘的空隙，奈米銀層則可以提供另條絕佳的導電路徑，而焦耳加熱退火處理則可以改善奈米碳管束與電極間的接觸電阻，使奈米碳管的電阻值獲得再進一步的改善。本研究以四點探針法進行電阻的量測及分析，每一步驟奈米碳管束的電阻改良都有很詳細的紀錄，其最終所形成的奈米碳管束的電阻值約為1 ohm左右，最後我們再進行奈米碳管束陣列式集束組裝的初步驗證，由實驗結果證實我們可以有效的控制單根奈米碳管束介電泳組裝的範圍，進而由單一的奈米碳管束組裝推廣至奈米碳管束的陣列組裝。

關鍵字

奈米材料；奈米碳管；介電泳組裝；微奈米機電製程技術

並列摘要

In this work, we propose a method of assembling carbon nanotubes (CNT) into a cluster by using dielectrophoresis. Multiwalled carbon nanotubes (MWCNTs), which have been acid-treated, are dispersed into ethanol solution. As the electric field is applied, the MWCNTs rotate to align with the external field direction by dielectrophoresis force, and then MWCNTs are attracted to the region of high field intensity. As ethanol solution evaporates, the surface tension act as a binding force to tie up MWCNTs, which are aligned with the external field direction, and form a MWCNTs cluster. Furthermore, we improved the conductivity of the MWCNTs cluster by dispersing silver nanoparticles into the MWCNTs cluster. Annealing process was also performed by using local joule heating. The resistance of the MWCNT clusters were measured by using four-point probe technique. The repeated experiment shows that measured electrical resistance of the assembled MWCNTs cluster is about 1 ohm. In addition, the method of forming array-type MWCNTs clusters was also proposed. The preliminary experimental results were also provided.

並列關鍵字

Carbon Nanotube ； Nano materials ； Micro and Nano Fabrication ； Dielectrophoretic Assembly

參考文獻

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[4] J. Hone, M. Whitney, C. Piskoti, and A. Zettl, "Thermal conductivity of single-walled carbon nanotubes," Physical Review B, vol. 59, pp. R2514-R2516, Jan 15 1999.

[5] G. S. Duesberg, A. P. Graham, M. Liebau, R. Seidel, E. Unger, F. Kreupl, and W. Hoenlein, "Growth of isolated carbon nanotubes with lithographically defined diameter and location," Nano Letters, vol. 3, pp. 257-259, Feb 2003.

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國際替代計量

利用介電泳組裝奈米碳管成束及其應用探討

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