可撓式塑膠基板低溫成長銦錫氧化物薄膜特性之研究 陳瀅照、王立民
E-mail: 9420021@mail.dyu.edu.tw
摘 要
本研究主要是探討以DC磁控濺鍍法分別於康寧玻璃基板Corning 1737F和PES光學級可撓式塑膠基板上鍍覆透明導電ITO薄 膜，研究探討低溫下製程ITO薄膜之其結構與光電特性之關係，以獲得最佳之成長條件。我們利用X-ray繞射儀來鑑定ITO 薄膜之磊晶方向；使用原子力顯微鏡來觀察其表面形貌與平整度；以及掃描式電子顯微鏡來觀察其薄膜/基座之界面型態
。另外，我們量測其電阻率、霍爾效應以及光穿透率，來鑑定其光電特性。 我們發現利用X-ray繞射儀來鑑定ITO薄膜之 磊晶方向，ITO薄膜具有(222)、(400)以及(440)之磊晶成長方向，另外，在相同的操作條件，隨著I(222)強度越強，所得 到ITO薄膜之電阻率越低。研究結果顯示，我們獲得最佳之製程條件為DC功率300 W，工作壓力在2 mtorr，工作溫度為室 溫，Ar和O2的比例為100：1。在此製程條件之下其中以康寧玻璃為基座：電阻率約為6.61X10-4 Ω cm，載子濃度
為2.31X1020 cm-3，在可見光範圍之穿透率可以達88 %；以PES光學級塑膠為基座：電阻率約為6.42X10-3 Ω cm，載子濃 度為1.13X1019 cm-3，在可見光範圍之穿透率可以達85 %。此結果與目前文獻之最佳條件值相較，顯現我們的ITO薄膜有 更好或相近之光電特性，此結果亦顯示，利用DC磁控濺鍍方式在室溫成長ITO薄膜，在本研究獲得之最佳成長參數之條 件下，無論在玻璃基板或PES塑膠基板上，我們均可獲得光電特性相當良好之ITO薄膜。
關鍵詞 : DC磁控濺鍍、PES、可撓式、ITO
目錄
封面內頁 簽名頁 授權書．．．．．．．．．．．．．．．．．．．．．．．．．iii 中文摘要．．．．．．．．．．．．
．．．．．．．．．．．．iv 英文摘要．．．．．．．．．．．．．．．．．．．．．．．．vi 誌謝．．．．．．．．．
．．．．．．．．．．．．．．．．．viii 目錄．．．．．．．．．．．．．．．．．．．．．．．．．．ix 圖目錄．．
．．．．．．．．．．．．．．．．．．．．．．．xii 表目錄．．．．．．．．．．．．．．．．．．．．．．．．
．xvii 第一章 緒論 1.1 透明導電膜．．．．．．．．．．．．．．．．． 1 1.2 研究背景與動機．．．．．．．．．．．
．．．． 3 第二章 理論基礎 2.1 銦錫氧化物薄膜簡介．．．．．．．．．．．．． 7 2.2 銦錫氧化物之結構簡介．．．．
．．．．．．．． 7 2.3 銦錫氧化物之電性．．．．．．．．．．．．．． 8 2.4 銦錫氧化物之光學性質．．．．．．．．
．．．． 9 2.5 濺鍍原理．．．．．．．．．．．．．．．．．．11 2.6 電漿原理．．．．．．．．．．．．．．．．．．
11 2.7 反應式磁控濺鍍．．．．．．．．．．．．．．． 13 2.7.1 濺射現象．．．．．．．．．．．．．．． 13 2.7.2 薄膜 沉積原理．．．．．．．．．．．．．16 2.8 塑膠基板低溫成長ITO薄膜．．．．．．．．．．18 2.9 新世代可撓式平面 顯示器塑膠基板的特性需求與特 點．．．．．．．．．．．．．．．．．．．．．19 2.10 新世代可撓式平面顯示器用塑 膠基板的材質種類 ．．．．．．．．．．．．．．．．．．．．． 22 第三章 實驗方法與步驟 3.1 實驗流程．．．．．
．．．．．．．．．．．．．25 3.2 實驗材料．．．．．．．．．．．．．．．．．．26 3.2.1 靶材．．．．．．．．．．
．．．．．．．26 3.2.2 基材．．．．．．．．．．．．．．．．．26 3.2.3 氣體．．．．．．．．．．．．．．．．．28 3.3 實驗方法．．．．．．．．．．．．．．．．．．28 3.3.1 實驗裝置．．．．．．．．．．．．．．．28 3.4 鍍膜參數 及步驟．．．．．．．．．．．．．．．29 3.4.1 鍍膜參數．．．．．．．．．．．．．．．29 3.4.2 基座清洗．．．．．
．．．．．．．．．．30 3.4.3 沉積ITO薄膜．．．．．．．．．．．．．30 3.5 薄膜性質測試與分析．．．．．．．．．
．．．．31 3.5.1 膜厚量測．．．．．．．．．．．．．．．31 3.5.2 霍爾效應量測．．．．．．．．．．．．．32 3.5.3 X-Ray繞射分析．．．．．．．．．．．．35 3.5.4 光學穿透率．．．．．．．．．．．．．．36 3.5.5 表面平坦度量測．
．．．．．．．．．．．37 第四章 結果與討論 4.1 ITO透明導電薄膜之成長特性與結構之研究．．．38 4.1.1 薄膜成長 速率之探討．．．．．．．．．． 38 4.1.1(a) DC功率之影響．．．．．．．．． 38 4.1.1(b) 工作壓力之影響．．．．．．
．． 38 4.1.1(c) 工作溫度之影響．．．．．．．． 39 4.1.2 製程參數對ITO薄膜結構之影響．．．．． 44 4.1.2(a) DC功率 之影響．．．．．．．．． 44 4.1.2(b) 工作壓力之影響．．．．．．．．45 4.1.2(c) 工作溫度之影響．．．．．．．．45 4.1.3 製程參數對ITO薄膜表面型態之探討．．． 58 4.2 製程參數對ITO薄膜光電特性之影響．．．．．．69 4.2(a) DC功率 之影響．．．．．．．．．．．．． 69 4.2(b) 工作壓力之影響．．．．．．．．．．． 77 4.2(c) 工作溫度之影響．．．．
．．．．．．． 85 4.3 製程參數對ITO薄膜影響之?合討論．．．．．．93 第五章 結論．．．．．．．．．．．．．．
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