臺灣博碩士論文加值系統

本論文主要目的在利用化學濕蝕刻方式探討AZO(ZnO:Al)薄膜於不同蝕刻參數下之蝕刻速率與蝕刻殘留之研究。首先藉由調控RF功率、基板溫度與高溫熱處理等參數來製備最佳之光電性之薄膜。其次，調控不同蝕刻溶液種類進行薄膜蝕刻後光電特性之探討。研究中利用薄膜段差測試儀量測薄膜沉積厚度與蝕刻速率、X-ray繞射儀分析薄膜結晶性、四點探針量測薄膜電性、紫外/可見光光譜儀量測薄膜於可見光穿透率、掃描式電子顯微鏡觀察電極圖案、能量散步光譜分析蝕刻殘留物。研究結果顯示本研究使用射頻磁控濺鍍製備AZO薄膜於1737F玻璃上，建議最佳製備條件為工作壓力1.0×10-2 torr、工作距離3.5cm、RF功率200W及基板溫度100℃時可獲得直鍍AZO薄膜電阻係數為1.18×10-2Ωcm、可見光穿透率均高於80%。若將直鍍AZO薄膜進行高溫熱處理(350℃-1小時)。可獲得更佳的AZO薄膜(電阻係數達2.38×10-3Ωcm、可見光穿透率高於85%)。進行稀釋王水(HNO3:HCl:H2O (1:4:1000))蝕刻溶液在25±1℃蝕刻速率>300nm/min，電阻率2.96×10-3 Ωcm，無蝕刻殘留。進行3.4wt.%草酸(Oxalic acid:H2O=4.76:95.24)蝕刻溶液在25±1℃蝕刻速率可達122nm/min，電阻率上升至3.61×10-3 Ωcm，蝕刻後有明顯殘留的現象，針對殘留物進行能量散步光譜分析發現殘留物為氧化鋅，造成殘留原因為單晶與非晶共同存在造成蝕刻速率不同所導致。兩種蝕刻液蝕刻過後可見光區皆有高達80%以上的穿透率。

頁次
摘要 ………………………………………………………………………. Ⅰ
謝誌 ………………………………………………………………………. Ⅲ
目次 ………………………………………………………………………. Ⅳ
表次 ………………………………………………………………………. Ⅶ
圖次 ………………………………………………………………………. Ⅷ

第一章 緒 論……………………………………………………………. 1
1.1 透明導電薄膜………………………………………………………… 1
1.2 研究動機與目的……………………………………………………… 2

第二章 文獻回顧…………………………………………....................... 4
2.1 透明導電膜於TFT-LCD之應用技術與原理.………………………. 4
2.1.1 TFT-LCD基本原理與結構….…………………………………. 4
2.1.2 薄膜電晶體(TFT)結構分類…………………………………… 5
2.1.3 Array TFT基板製作流程………………………………………. 5
2.2 透明導電薄膜材料與製程………………………………….………... 9
2.2.1透明導電膜材料………………………………………………... 9
2.2.2 AZO透明導電薄膜…………………………………………….. 9
2.2.3 透明導電薄膜製備…………………………………………….. 11
2.3 AZO透明導電薄膜製程參數對微結構及光電性質之影響……….. 14
2.3.1基板溫度……………………………........................................... 14
2.3.2 RF功率…………………………………………………………. 17
2.3.3 退火條件……………………………………………………….. 21
2.4 透明導電膜蝕刻製程………………………………………………… 25
2.4.1濕蝕刻方式……………………………………………………... 25
2.4.2乾蝕刻方式……………………………………………………... 27
2.5 微結構對透明導電膜濕蝕刻性質之影響…………………………… 29
2.6 濕蝕刻製程參數對透明導電膜蝕刻性質之影響…………………… 33

第三章 研究方法………………………………………………………... 39
3.1 實驗流程……………………………………………………………… 39
3.2 實驗步驗……………………………………………………………… 39
3.2.1試片準備………………………………………………………... 39
3.2.2薄膜沉積………………………………………………............... 42
3.3 薄膜特性分析………………………………………………………… 44
3.3.1沉積速率量測………………………………………................... 44
3.3.2微結構分析……………………………………………………... 45
3.3.3電學性質量測…………………………………………………... 46
3.3.4光學性質量測…………………………………………………... 47
3.4 AZO與ITO透明導電膜蝕刻……………………………………….. 48
3.4.1蝕刻溶液選擇…………………………………………………... 48
3.4.2蝕刻實驗………………………………………………............... 48
3.4.3蝕刻速率量測……………………………………....................... 51
3.4.4蝕刻圖形定義……………………………………....................... 51
3.4.4蝕刻圖形殘留分析………………………………....................... 51

第四章 結果與討論……………………………………………………... 53
4.1 ZnO:Al 薄膜之成長特性……………………………………………. 53
4.1.1製程參數對沉積速率之影響……………………………........... 53
4.1.2製程參數對晶體結構之影響…………………………………... 54
4.2 製程參數對光電性質與結構之關係………………………………… 58
4.2.1製程參數對電性質之影響………………………………........... 58
4.2.2製程參數對光性質之影響……………………………………... 58
4.2.3最佳AZO薄膜製程參數…………….…………………………. 59
4.3 透明電極蝕刻特性之研究…………………………………………… 64
4.4.1蝕刻參數對薄膜蝕刻率之影響……………………………….. 64
4.3.2蝕刻液對薄膜電性之影響……………………………………. 64
4.3.3蝕刻液對薄膜光性之影響…………………………………… 64
4.3.4不同蝕刻溶液對AZO蝕刻殘留之影響………………………. 68
4.4 最佳蝕刻參數討論…………………………………………………… 69

第五章 結論與未來研究………………………………………………... 74
5.1 結論…………………………………………………………………… 74
5.2 未來研究……………………………………………………………… 75
參考文獻…………………………………………………………………... 76

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