過渡金屬硫族化合物為新穎之二維材料，豐富的物理與優異的材料特性讓該材料獲得國際高度關注。本論文藉由常壓下之化學氣相沉積法，合成高品質之單層二硫化鎢材料，結合不同促進劑之使用，調控二硫化鎢的合成反應與摻雜，並透過各種參數調控，深入探討促進劑對於二硫化鎢合成的影響，了解促進劑於材料合成過程中之生長機制，及材料物理性質的改變。
　　本研究成功在較低溫的常壓環境，合成出大面積二硫化鎢，並發現促進劑的添加，會對材料產生氯摻雜效果，並利用掃描穿隧顯微術觀察並解析摻雜二硫化鎢的原子結構，而此氯摻雜能促進二硫化鎢的光學特性，預期摻雜的調控與其機制，將對於未來二硫化鎢在光學與各項基礎研究上的相關研究，有重要幫助。

　　Transition Metal Dichalcogenides (TMDs) is one of emergent two-dimensional material family that is widely highlighted because of novel physical phenomenon and excellent optoelectronic properties. In this thesis, we study growth mechanism of the synthesized monolayer of tungsten disulfide (WS2) by ambient-pressure chemical vapor deposition (APCVD) synthesis with different promoters. Growth behaviors and diverse physical properties of the monolayer will be discussed and presented.
We successfully synthesized large-area tungsten disulfide in low-temperature ambient pressure and the controlled doping of the synthesized monolayer is achieved by using halide promoter. Ultra-clean monolayer transfer enables clear and detailed characterizations of the Cl dopants with atomically-resolved scanning tunneling microscope (STM) experiments. Optical properties of the grown Cl-doped WS2 were significantly enhanced. We expected that the controlled doping and monolayer synthesis would open a new avenue toward novel 2D nano-photonics and high performances electronics.

第一章 緒論 5
第二章 文獻回顧 7
2-1　過渡金屬硫族化合物 7
2-1-1　晶體結構 7
2-1-2　電子能帶結構 7
2-1-3　能谷電子學 (Valleytronics) 9
2-1-4　光學性質 9
2-2　過渡金屬硫族化物的製備方法 11
2-2-1　機械剥離法 11
2-2-2　化學離子插層法 11
2-2-3　物理氣相沉積法 12
2-2-4　化學氣相傳輸法 12
2-2-5　化學氣相沉積法 13
2-3　化學氣相沉積法合成過渡金屬硫化物的重要參數 14
2-3-1　溫度 14
2-3-2　還原氣氛 15
2-3-3　化學反應途徑 15
2-4　二維材料之掃描穿隧顯微術分析 17
2-4-1　過渡金屬硫族化合物之原子級檢測 17
2-4-2　過渡金屬硫族化合物之缺陷類型 18
第三章 實驗方法 27
3-1　實驗大綱 27
3-2　實驗系統 28
3-2-1　試片前處理 28
3-2-2　實驗步驟 28
3-3　材料分析與量測 31
3-3-1　光學顯微鏡 31
3-3-2　拉曼光譜分析 31
3-3-3　光致螢光光譜分析 32
3-3-4　掃描穿隧電子顯微鏡 33
3-3-5　歐傑電子能譜儀 35
3-3-6　X射線光電子能譜 35
第四章 二硫化鎢的合成與分析 41
4-1　概述 41
4-2　促劑進對二硫化鎢生長的影響 42
4-2-1　使用PTAS作為促進劑對二硫化鎢生長的影響 43
4-2-1-1　PTAS濃度對二硫化鎢生長的影響 43
4-2-1-2　PTAS在不同反應溫度對二硫化鎢生長的影響 45
4-2-1-3　還原氣氛(氫氣)的影響 45
4-2-2　使用氯化鉀作為促進劑對二硫化鎢生長的影響 50
4-2-2-1　還原氣氛(氫氣)的影響 51
4-2-2-2　硫反應物進入時間的影響 52
4-2-2-3　鹼金屬鹵化物(氯化鉀)用量的影響 53
4-2-2-4　總結 53
4-2-3　PTAS與氯化鉀對二硫化鎢生長的差異 54
4-3　摻雜之二硫化鎢 60
4-3-1　摻雜之二硫化鎢材料 60
4-3-2　歐傑電子能譜分析 60
4-3-3　掃描穿隧顯微術分析 61
4-3-4　光致螢光光譜分析 62
4-3-5　拉曼光譜分析 63
4-3-6　X射線光電子能譜分析 64
第五章 結論 72
參考文獻 74

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