近年來，矽基半導體於尺度微小化及相關應用，相關製程及技術受限於材料極限遇到相當大的瓶頸。過渡金屬二硫屬化物為新穎的二維半導體，其優異的物理與化學特性，受到高度重視。本論文，以化學氣相沉積法合成單分子層二硫化鉬及二硫化鎢，藉由調控製程系統中各項影響反應的參數，控制過渡金屬二硫屬化物的成長、摻雜及異質結構，解釋其成長機制，並深入探討其物性。
摻雜物對二硫化鎢的光學特性造成顯著影響，有助於光學及光電相關之應用。藉由優化的製程，以多階段化學氣相沉積法實現二硫化鉬及二硫化鎢之側向異質磊晶成長。除光學及各項分析，更進一步以掃描穿隧顯微術，深入分析所合成試片的原子結構與表面物理，深入探討單層二維半導體之摻雜及側向異質介面之基礎研究，證明化學氣相沉積法為一理想之合成二維半導體的技術，並成功結合表面分析技術而獲得珍貴的物理特性觀察。

In recent years, semiconductors industry meet diverse challenges on manufacturing process due to the material limit of the silicon. Monolayer semiconductors of the transition metal dichalcogenides (TMDs) are considered as one possible alternative solution for the challenges in the industry and scientific community because of their unique structures and diverse properties.
In this work, we present the growth of monolayer 2D lattices with ambient pressure chemical vapor deposition (APCVD). We focus on the synthesis of three representative systems: (1) individual TMD monolayer, (2) lateral heterojunction of monolayer TMD and (3) doped monolayers. In the first part, various growth parameters, including precursors, reactant concentrations, gas flow, temperature, growth rate and some factors, are carefully studied and further control synthesis in specific growth behaviors of the tungsten disulfide(WS2) and the molybdenum disulfide(MoS2) on sapphire or SiO2 substrate. With the experience on the growth mechanism, lateral heterojunction of the monolayer TMDs are realized in the second part and further studied with STM analysis and related characterizations. In the third part, we demonstrated the synthesis of doped WS2. Compared to intrinsic monolayer TMDs, doped WS2 exhibits excellent optical properties and hold the promise for optoelectronic applications. STM analysis provides essential evidences at atomic level for better understanding of the doped TMDs, lateral heterojunctions, and related physical properties.

摘要 0
Abstract 0
致謝辭 1
目錄 0
圖目錄 3
第一章 緒論 6
第二章 文獻回顧 8
2-1. 過渡金屬硫屬化物 (TMDs)介紹 8
2-1-1晶體結構 8
2-1-2電子能帶結構 8
2-1-3 能谷電子學 (Valleytronics) 9
2-1-4光學性質 10
2-2. 過渡金屬硫屬化物(TMDs)製備方法 11
2-2-1 機械剥離法 11
2-2-2 化學離子插層法 12
2-2-3化學氣相沉積法 12
2-3. 過渡金屬硫屬化物異質結構 13
2-3-1 二維材料異質結構的製備 13
2-3-2 側向式異質結構 14
2-4. 過渡金屬硫屬化合物之掃描穿隧顯微術分析 15
2-4-1 過渡金屬硫屬化合物之顯微術 15
2-4-2 過渡金屬硫屬化合物之缺陷類型 15
2-4-3 過渡金屬硫屬化合物之莫瑞圖紋 (Moiré Pattern) 16
第三章 實驗方法 24
3-1 實驗大綱 24
3-2實驗系統 25
3-2-1試片處理 25
3-2-2 實驗步驟與說明 25
3-3 材料分析與量測 28
3-3-1 光學顯微鏡 28
3-3-2 拉曼光譜儀 28
3-3-3 光致螢光光譜 29
3-3-4 掃描穿隧顯微鏡(STM) 30
3-3-5 歐傑電子能譜儀(AES) 32
第四章 二維半導體(TMD)的成長 37
4-1 單層TMD之晶體成長與製程控制 37
4-1-1 反應物(濃度及比例)對於成長行為的影響 37
4-1-2 還原氣氛對於成長行為的影響 38
4-1-3 晶種(PTAS)濃度對於成長行為的影響 39
4-1-4 二維半導體之生長機制 39
4-2單層二維材料異質結構 (側向WS2-MoS2異質結構) 40
4-2-1二維材料異質結構之成長 40
4-2-2二硫化鎢與二硫化鉬之側向異質結構 41
4-3 摻雜之二維半導體 42
4-3-1摻雜之二維半導體成長 42
4-3-2摻雜之二維半導體的光學性質(二硫化鎢)的光學性質 42
4-3-3摻雜之二維半導體的化學組態分析(AES) 42
4-3-4摻雜之二維半導體的掃描穿隧顯微術分析 (STM) 43
第五章 結論 55
參考文獻 56
附錄: 期刊發表 58

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