本篇論文的主要工作內容聚焦於二維半導體成長的大面積製程，使用化學氣相沉積法合成高品質之單層二硫化鉬，並以高溫退火反應法，將預鍍之反應物進行硫化或碲化反應，以合成大面積且均勻的二維半導體。本研究藉由改變參數，深入研究各項製程參數對成長的影響，進一步藉由調控溫度、反應物濃度，以及環境氣氛，以實現二維材料之大面積製程。在本研究中，高溫退火反應(硫化/碲化)法合成的材料，具有相當高的均勻性且製程參數穩定。這個製程的優點在於良好的均勻性、製程容易控制、簡單，能合成出大面積的材料，然而其電性的表現較為不佳，需要一定厚度才能均勻，需要有改善品質的方法或是使用化學氣相沉積法來合成高品質二硫化鉬。

In this research, we used chemical vapor deposition to synthesize monolayer MoS2. Sulfurization and tellurization was used to synthesize scalable size of MoS2、MoTe2 by sulfurizing or tellurizing pre-deposited MoO3 on the substrate.The influence of growth parameters was investigated, such as concentration of precursor vapor、growth temperature and pressure, trying to realize scalable synthesis of two-dimensional semiconductor. The advantages of sulfurization and tellurization were its high uniformity、good controbility. But the mobilities of MoS2 synthesized by Sulfurization were relatively low compared to MoS2 synthesized by chemical vapor deposition.

目錄 5
圖表目錄 8
第一章 研究動機 12
第二章 文獻回顧 15
2-1 過渡金屬硫族化合物 15
2-1-1 晶體結構 15
2-1-2 能帶結構. 16
2-1-3 TMD之電學特性 17
2-1-4 光電性質 19
2-2 過渡金屬硫族化合物的合成 20
2-2-1 機械剝離法 20
2-2-2 鋰離子插層法 20
2-2-3 物理氣相沉積 21
2-3 大面積成長過渡金屬硫族化合物之製程 21
2-3-1 硫化反應 21
2-3-2 化學氣相沉積 22
2-3-3 有機金屬化學氣相沉積 22
2-4 二維材料之檢測技術 23
2-4-1 拉曼光譜分析 23
2-4-2 光致螢光光譜分析 24
第三章 實驗方法 32
3-1 實驗大綱 32
3-2　實驗準備與實驗架設 33
3-2-1　基板前處理 33
3-2-2 合成步驟 33
3-3 材料分析與量測 34
3-3-1 光學顯微鏡 34
3-3-2 拉曼光譜儀 34
3-3-3 光致發光光譜分析 34
3-3-4　晶體結構分析 35
3-3-5　表面形貌與厚度觀察 35
3-3-6　表面成分分析 35
3-3-7　電性及光電性質量測 36
第四章 化學氣相沉積法合成高品質二硫化鉬 40
4-1 製程參數對二硫化鉬生長的影響 40
4-1-1 前言 40
4-1-2 硫反應量對生長之影響 40
4-1-2 還原氣氛對生長之影響 40
4-1-3 鉬反應量對生長之影響 42
4-1-4 反應物( MoO3、S)比例對材料生長之影響 44
4-1-5 坩堝位置對前驅物蒸氣之影響 44
4-1-6 工作壓力對反應物均勻度之影響 44
4-1-7 工作壓力對反應物濃度之影響 46
4-1-8 基板種類與晶種(seeding promoter)對生長之影響 47
4-2 單層二硫化鉬之電性與光電量測 49
4-3 總結與未來工作 50
第五章高溫退火(硫化、碲化)反應實現二維半導體之大面積合成 63
5-1 前言 63
5-2 二硫化鉬之合成 64
5-3 二碲化鉬之合成 66
5-4 結論與未來工作 66
第六章 參考文獻 81

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