以噴射式大氣電漿進行具奈米結構金屬氧化物之製程研究

本文為利用噴射式大氣電漿系統進行電漿輔助奈米結構製程之實驗研究。實驗使用金屬薄片作為前驅物，將前驅物置於電漿噴流區進行氧氣電漿處理，經短時間(約數十秒)即可製成具奈米結構之金屬氧化物材料。本研究使用鈮、鈦等高熔點金屬分別製成了氧化鈮奈米線結構以及氧化鈦顯微球型結構，改變電漿參數對於製程的影響上，發現改變操作電壓可以調整奈米結構成長的速率，改變氣體流量則會影響奈米結構生成與否；另外，由於奈米結構為由基材成長垂直於平面之結構，金屬原子在基材中的擴散速率對成長速率的影響，也在氧化鈮奈米線的實驗中被展示出來。氧化鈮奈米線結構在本文中有較深入的研究，如氧化鈮奈米線成長機制討論、使用APPJ電漿系統的掃描模式進行大面積製程、使用AFM以局部氧化方式嘗試定位出奈米線生長出區域以及對於氧化鈮奈米線進行了XRD、拉曼光譜、TEM等儀器分析。氧化鈦顯微球型結構則進行了關於球型結構隨著時間成長情況之研究以及使用XRD對其結晶型態進行分析等。其他低熔點金屬，如錫、鉛、鋅，由於電漿噴流溫度高於金屬熔點以及快速氧化反應所放出之高反應熱，使得基材發生熔化現象，並無觀察到奈米結構之生成。為了瞭解電漿參數對於電漿特性之影響，使用了熱電偶以及光譜儀對於電漿氣體溫度以及電漿放射光譜進行檢測。電漿氣體溫度與操作電壓成正相關，與氣體流量成負相關，電漿放射光譜則隨著操作電壓以及氣體流量上升而增強，相關機制在文中會進行詳細敘述。另外，在電漿噴頭上配置隔絕大氣玻璃管則發現了有趣的現象，即代表O radical之特徵放射光強度顯著增強，可能的原因為玻璃管將激發態O2以及O3等反應性高產物束縛在電漿噴流區，進而發生解離反應使得O radical的濃度上升。

關鍵字

大氣電漿；金屬氧化物；具奈米結構；氧氣電漿檢測

並列摘要

A method of synthesis of nanostructured metal oxide using an atmospheric pressure plasma jet (APPJ) was performed in this work. Solid metal foils were placed under the APPJ system as precursors. The nanostructured metal oxide was fabrication after tens of seconds of oxygen plasma treatment. Niobium oxide nanowire and titanium dioxide spheric microstructure were fabricated using this method. Parametric studies show that a high growth rate can be obtained with the synergetic effect of the high temperature and plasma reactivity. The process of fabricating niobium oxide nanowires was detailed studied. The structural analysis shows that for the case in which no nanowires is formed, the major phases are Nb6O and orthorhombic Nb2O5 phases while in the case with the presence of NWs, highly crystalline monoclinic Nb2O5 is the dominant phase. Preliminary test shows that nanowires can be fabricated using the “scanning mode” of this jet, which suggests the potential using this plasma jet to continuously fabricate nanowires in a larger area. Zinc、lead and tin were also used, but there is no nanostructure formation since the temperature of plasma jet is well above to the melting point of these metals. The diagnostic studies of atmospheric oxygen plasma were also performed. The properties of plasma was measured using a k-type thermocouple with protective sheath and an optical emission spectroscopy. The intensity of characteristic peak of O radicals become stronger after the nozzle surrounded by a glass tube. Since high reactivity is desirable, the main factors to cause this dramatic increase were also studied in this work.

並列關鍵字

atmospheric pressure plasma ； Nanostructured metal oxide ； oxygen plasma diagnostic

參考文獻

[33] S. Rackauskas, A.G. Nasibulin, H. Jiang, Y. Tian, V.I. Kleshch, J. Sainio, E.D. Obraztsova, S.N. Bokova, A.N. Obraztsov, E.I. Kauppinen, A novel method for metal oxide nanowire synthesis, Nanotechnology 20 (2009) 8.

[1] S. Amelinckx, X.B. Zhang, D. Bernaerts, X.F. Zhang, V. Ivanov, J.B. Nagy, A formation mechanism for catalytically grown helix-shaped graphite nanotubes, Science 265 (1994) 635.

[2] I. Denysenko, K. Ostrikov, Plasma heating effects in catalyzed growth of carbon nanofibres, Journal of Physics D-Applied Physics 42 (2009).

[3] C.H. Weng, C.S. Yang, H. Lin, C.H. Tsai, K.C. Leou, Low temperature synthesis of single-walled carbon nanotubes in an inductively coupled plasma chemical vapor deposition system, J. Nanosci. Nanotechnol. 8 (2008) 2526.

[4] E.J. Bae, Y.S. Min, U.J. Kim, W.J. Park, Thin film transistors of single-walled carbon nanotubes grown directly on glass substrates, Nanotechnology 18 (2007) 4.

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以噴射式大氣電漿進行具奈米結構金屬氧化物之製程研究

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