本研究發展以電漿輔助式化學氣相沉積法(Plasma-enhanced Chemical Vapor Deposition, PECVD)低溫合成高品質之單壁奈米碳管(Single-walled Carbon Nanotube, SWNT)方法，主要探討離子屏蔽與氧氣之影響。離子屏蔽即在電漿與基板間以擋板(Shutter)隔離，降低離子轟擊奈米碳管的效應。此外，亦探討在製程之碳氫氣體中加入微量之氧氣，對PECVD合成單壁奈米碳管之影響。所合成之碳管主要以拉曼光譜分析其石墨化品質與產量，此外，並以掃描式電子顯微鏡(Scanning Electron Microscopy, SEM)與穿透式電子顯微鏡(Transmission Electron Microscopy, TEM)分別檢視成長之試片表面形貌與碳管結構。本研究並以電漿放射光譜(Optical Emission Spectrum, OES)探討製程中電漿環境的改變，以了解氧氣影響單壁奈米碳管品質及產量之因素。
實驗結果顯示，本研究成功以PECVD方法於低溫合成單壁奈米碳管，且離子屏蔽成功抑制離子轟擊(Ion Bombardment)，而獲得較佳品質的單壁奈米碳管。在離子屏蔽下，碳管品質隨電漿功率及氫氣比例下降而提升；單壁奈米碳管的品質隨著成長時間增加而提升，15至20分鐘時仍可維持穩定，產量隨著成長時間增長而增加。於500 ℃下，氣體比例CH4/H2 = 120/0 sccm/sccm，電漿功率30 W時，獲得最佳品質之單壁奈米碳管，並以此為基礎進行氧氣輔助之研究。
　　在離子屏蔽下，通入微量氧氣輔助碳管成長，發現當氧氣比例為0.25 %時，單壁奈米碳管之品質可微幅提昇。此外，隨著成長時間增加，單壁奈米碳管品質與產量隨之增加，說明了降低離子轟擊效應對於提升碳管品質之效果遠高於氧氣輔助的成效。因此在擋板結構下，仍可維持穩定品質之單壁奈米碳管。並在離子屏蔽與氧氣輔助之效應的研究中發現，同在擋板結構下，氧氣輔助並無有效提升單壁奈米碳管品質。另一方面，受到擋板保護的單壁奈米碳管品質與產量遠高於不受擋板保護之單壁奈米碳管，相關實驗結果顯示，對奈米碳管品質提升而言，擋板結構屏蔽離子轟擊的貢獻遠高於氧氣平衡C與H之自由基的效應。
經由電漿光譜量測，發現Hα、CH與Hβ之訊號在含氧氣環境中較弱，可能的原因為氧氣與H2及CHx反應生成OH等自由基，平衡製程環境中C與H自由基而獲得較高品質之SWNTs。
　　此外，在氧氣輔助的部份提出另一種可能的機制：由於氧氣是電負性(Electronegative)氣體，使得電漿電位降低，離子轟擊因而減弱，進而獲得較高品質與產量的奈米碳管。

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