過渡金屬硫族化合物具有特殊的能帶結構、強自旋軌域耦合特性，在元件表現上有獨特的光學與電學特性，受到國際高度重視。本論文主要藉由化學氣相沉積法合成二硒化鎢與相異二維半導體材料之異質結構並探討製程參數對二硒化鎢合成的成長行為。以二硒化鎢成長行為的研究為基礎，提出一階段製程與二階段製程合成過渡金屬硫族化合物異質結構，如二硒化鉬/二硒化鎢，二硒化鎢/二硫化鉬等，並製備成下閘級式場效電晶體，探討其電學性質，其中二硒化鎢呈現雙級性半導體特性，二硒化鎢/二硫化鉬異質結構具有整流特性。最後，探討過渡金屬硫族化合物在不同工作氣氛下的材料穩定度，以實現二維半導體異質結構之生長。

Transition metal dichalcogenides (TMDc) have attracted attention due to unique band structure and spin valley coupling for electronics and optoelectronics. In this research, tungsten diselenides (WSe2) and TMDc heterostructures were synthesized by chemical vapor deposition. Based on the study of WSe2 growth behavior, we developed the one-step process and two-step process to synthesize TMDc heterostructures, such as MoSe2/WSe2 and WSe2/MoS2. In addition, we report the fabrication of back-gate field effect transistors based on WSe2 and TMDc heterostructures. The WSe2 transistor demonstrated ambipolar operation, and WSe2/MoS2 heterostructures displayed rectifying characteristic. Finally, to achieve the growth of the varying TMDc heterostructures, we discussed the stability of the TMDc materials in different working atmosphere

目錄 1
圖目錄 5
第一章 研究動機 9
第二章 文獻回顧 11
2-1過渡金屬硫族化合物 11
2-1-1 化學式與晶體結構 11
2-1-2 能帶結構 11
2-1-3 電子傳輸特性 12
2-1-4 光電特性 13
2-2過渡金屬硫族化合物之異質結構 14
2-2-1 異質結構的種類 14
2-2-2 異質結構之特殊性質 15
2-3二維材料之檢測技術 16
2-3-1 拉曼光譜分析(Raman Spectrum) 16
2-3-2 光致發光光譜分析Photoluminescence Spectrum(PL) 17
2-3-3 原子力顯微鏡Atomic Force Microscope(AFM) 18
2-3-5 歐傑電子能譜儀Auger electron spectroscopy(AES) 19
2-4 過渡金屬硫族化合物的合成 19
2-4-1 機械剝離法(mechanical exfoliation) 19
2-4-2 物理氣相沉積(Physical Vapor Deposition) 20
2-4-3 化學氣相沉積(Chemical Vapor Deposition) 20
2-4-4 有機金屬化學氣相沉積(MOCVD) 21
2-5 二維材料異質結構之合成與分析 21
2-5-1 水平方向異質結構合成-一階段製程 21
2-5-2 水平方向異質結構合成-二階段製程 22
2-5-3 垂直二維半導體異質結構之合成 24
第三章 實驗方法 36
3-1 實驗大綱 36
3-2　實驗準備與實驗架設 36
3-2-1 試片前處理 36
3-2-2 合成步驟 37
3-3 材料分析與量測 38
3-3-1 光學顯微鏡 38
3-3-2 拉曼光譜儀 39
3-3-3 光致發光光譜分析 39
3-3-4　表面形貌與厚度觀察 39
3-3-5　表面成分分析 40
3-3-6　電性量測 40
第四章 二硒化鎢的合成與分析 44
4-1 製程參數對二硒化鎢生長行為的影響 44
4-1-1 製程溫度 44
4-1-2 還原氣氛 45
4-1-3 基板效應 45
4-1-4 晶種效應 46
4-1-5前驅物含量對成長的影響 - 硒 48
4-1-6 前驅物之比例W/Se 48
4-2 二硒化鎢之光學檢測 49
4-3 二硒化鎢之電性量測 51
第五章 二硒化鎢之異質結構 58
5-1 一階段製程合成異質結構 58
5-1-1 二硒化鉬/二硒化鎢異質結構之合成 58
5-1-2 二硒化鉬/二硒化鎢異質結構之初部分析 59
5-1-3 二硒化鉬/二硒化鎢異質結構之進階分析 60
5-2 二階段製程異質結構 60
5-2-1 二硫化鎢/二硒化鎢之合成與分析 61
5-2-2二硒化鎢/二硫化鉬之異質結構合成與分析 62
5-4二維材料之穩定度 63
5-3 二硒化鎢/二硫化鉬之電性量測 63
第六章 結論 71
參考文獻 73
附錄: 期刊發表與研究獲獎 78

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