透過電泳技術沉積奈米碳管及其場發射之應用

DEPOSITION OF CARBON NANOTUBES BY ELECTROPHORETIC TECHNIQUE FOR FIELD EMISSION APPLICATION

劉佑成(Yu-Cheng Liu)

指導教授 ： 施文欽

大同大學/電機資訊學院/光電工程研究所/碩士(2010年)

摘要

本論文主要研究目的為利用奈米碳管的極佳物理特性(高電流密度及低導通電場)並將其製備電泳懸浮液。電泳奈米碳管沉積在ITO基板上之製程已成功被開發。實驗的製程參數包括：電泳沉積時間、電泳施予之外加電壓、陽極與陰極間之距離以及方波波型之電泳沉積。
本研究所採用的陽極與陰極基板分別為金電極與ITO電極運用電泳沉積技術，在ITO玻璃基板上完成二極式場發射背光元件，沉積物之結構與性質將利用場發射J-E量測系統、拉曼光譜分析(Raman spectroscopy)、場發射掃描式電子顯微鏡(FESEM)加以分析。
本研究為使用電泳沉積的方式製備奈米碳管場發射陰極，主要分為三大部分，第一部份為直流電壓電泳沉積性質的分析。懸浮液主要使用異丙醇當作承載溶液，並添加硝酸鎂為攜帶奈米碳管之載子。藉由電泳時沉積之電壓、電流與時間關係，一般而言電壓越高電泳泳動速率快，因此擴散時間短分離效果也較好，藉此瞭解在直流電泳沉積下對於場發射的效果。第二部份為非直流電泳時沉積之電壓、頻率與工作週期之分析。實驗則使用訊號產生器以及示波器輸出正確之方波脈衝電壓及頻率值，由實驗結果可知脈衝電泳具有高電流密度的極佳物理特性。第三部份則為製作場發射顯示光源之元件並完成二極式場發射光源。

關鍵字

電泳沉積 ； 奈米碳管 ； 場發射

並列摘要

The main purpose of this thesis is to use the excellent physical properties of carbon nanotubes such as high current density and low turn-on electric field for the emitter of the flat light source. Electrophoretic deposition of carbon nanotubes on the ITO substrate manufacturing process has been developed successfully. Experiment process parameters include: electrophoretic deposition time, applied voltage for the process , the distance between anode and cathode as well as square-wave type of electrophoretic deposition.
In this study, the anode and cathode are gold electrode substrate and ITO electrode substrate respectively. Using the electrophoretic deposition technique, we complete the two-pole field emission backlight component on the ITO glass substrate. We use the field emission measurement system, Raman spectroscopy, and field emission scanning electron microscopy (FESEM) to analysis samples structure and nature of the sediment.
In this study, the way for using electrophoretic deposition technique to fabricate Carbon Nanotubes Field Emission Cathode is divided into three parts：The first part is DC voltage electrophoretic deposition. Using isopropyl alcohol as the main suspension bearing solution, we also add the paste of magnesium nitrate as carbon nanotubes carrier. By the control of electrophoresis deposition voltage, applied current, and deposition time, we reached the conclusion that in the higher applied voltage,the mobility rate is faster and the diffusion time is shorter, and these make good effect in seperation. The second part is the non-DC voltage electrophoresis deposition, and we make analysis in voltage, frequency, and duty cycle. The experiment was performed using a signal generator and the oscilloscope, reading the output of the correct square wave pulse voltage and frequency value, we come to the conclusion that pulse electrophoresis deposition has higher current density, and this is we want. The third part is the production of field emission lighting device, completing the planar field emission light source.

並列關鍵字

electrophoretic deposition ； field emission ； carbon nanotube

參考文獻

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