矽製程近幾年來受到短通道效應的影響相當嚴重，因此二維材料成為了下個世代重點的發展目標，但二維材料無懸鍵的表面將使的金屬與材料間存在電子較難通過的凡德瓦間隙，且二維材料極薄的特性使其無法對接觸面做離子佈值的重摻雜，使元件效能低下。
本論文使用氬氣離子對金半介面在沈積金屬前先做表面處理，並預期此處理技術可以增加金半間的接觸特性，甚至互相產生鍵結，使電子注入效率得以提高，再使用半金屬鉍和文獻中最優秀的接觸金屬鈦做一個比對，製作出最佳化的硒氧化鉍電晶體，元件效能的部分使用鈦作為接觸金屬輔以氬氣離子的處理使得背閘極元件的電子遷移率最高達到769 (cm2/V·s)，開關比最高來到巨幅的109，接觸電阻則為1004.21 (Ω·μm) ，這些數據超越了幾乎絕大多數的文獻及期刊，顯示了極為良好的接觸特性。

In recent years, silicon processes have been significantly affected by the short-channel effects. As a result, two-dimensional materials have become the focus of development for the next generation. However, the dangling bond-free surface of two-dimensional materials creates van der Waals gaps that hinder electron transport between metals and materials. Additionally, the ultrathin flakes of two-dimensional materials are unable to undergo implantation to narrow the Schottky barrier.

In this thesis, argon ion treatment was applied to the metal-semiconductor interface before metal deposition. It is anticipated that this treatment technique can enhance the contact qualities between metal and the semiconductor, potentially forming bonds between them. This could improve electron injection efficiency. By using semimetallic bismuth and the best-performing contact metal titanium in
iteratures, an optimized Bi2O2Se transistor was fabricated.

Titanium was used as the contact metal with argon ion treatment, and the electron mobility of 769 (cm2/V·s) for the back-gate field-effect transistor was obsevred. The on/off ratio reached an impressive value of 109, and the contact resistance was measured at 1004.21 (Ω·μm). These data surpass the majority of existing literature and journal reports, suggesting exceptional contact characteristics.

摘要 i
Abstract ii
致謝 iii
目錄 v
第 1 章 序論 1
1.1 半導體發展史 1
1.2 矽製程的微縮與其限制 2
1.3 二維材料發展簡介 3
1.4 論文架構 7
第 2 章 硒氧化鉍物理特性 8
2.1 硒氧化鉍簡介 8
2.2 硒氧化鉍晶體組成結構 9
2.3 硒氧化鉍之電子能帶 10
2.4 硒氧化鉍之載子傳輸機制 11
2.5 硒氧化鉍之自體摻雜機制 12
2.6 硒氧化鉍之成長機制 13
2.6.1 硒氧化鉍之成長機制 13
2.6.2 傾斜式成長 14
2.6.3 鈦酸鍶基板成長 17
2.6.4 金半接觸討論 20
第 3 章 硒氧化鉍材料檢測 28
3.1 光學式顯微鏡 28
3.2 拉曼光譜儀分析 29
3.3 掃描式電子顯微鏡 SEM 33
3.4 穿透式電子顯微鏡 TEM 35
3.4.1 平面觀測 35
3.4.2 FIB 截面觀測 36
第 4 章 硒氧化鉍場效電晶體製程介紹 39
4.1 材料製備 39
4.1.1 化學氣相沉積 39
4.1.2 脈衝雷射沉積 48
4.2 材料蝕刻 51
4.2.1 反應離子蝕刻 52
4.2.2 溼式蝕刻 53
4.3 氧化層製備 56
4.3.1 加熱自氧化 57
4.3.2 光輔助自氧化 57
4.4 材料轉印法 58
4.4.1 濕式轉印法 58
4.4.2 乾式轉印法 59
4.5 退火 61
4.6 微影製程 62
4.6.1 曝光機微影系統 64
4.6.2 DLP 曝光系統 66
4.6.3 電子束微影系統 67
4.7 金屬蒸鍍 69
4.7.1 電阻式熱蒸鍍系統 69
4.7.2 電子槍蒸鍍系統 71
4.8 特殊上閘極製作 72
第 5 章 實驗結果與討論 74
5.1 元件量測 75
5.1.1 元件量測系統 75
5.1.2 元件結構 76
5.2 輸出特性曲線量測 77
5.2.1 離子源處理接觸分析 77
5.2.2 鈦、鉍輸出特性曲線分析 84
5.3 轉移曲線量測 87
5.3.1 雙閘極量測 95
5.4 傳輸線模型量測 96
5.5 變溫量測與蕭特基能障分析 103
第 6 章 結論與未來展望 109
參考文獻 110

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