此論文以超高真空系統之掃描式穿隧電子顯微鏡，觀察單層二維半導體之堆疊造成電子結構的變化，探討二維半導體於堆疊組態下的莫瑞圖紋及相關新穎現象。
本研究中，以化學氣相沉積合成的二硫化鉬為二維半導體的代表，於超高潔淨的表面及介面品質下，因轉移而人為產生的特殊堆疊，相異堆疊夾角，及各種堆疊組態，提供二維材料於堆疊時所產生的電子結構變化及層間耦合效應。經由表面結構及電子結構的原子解析影像觀察，確認材料轉移過程具有極高潔淨度。
透過觀察二維晶體堆疊後的電子結構，發現多組因堆疊角度差異所形成之莫瑞圖紋。此莫瑞圖紋的週期性位能變化，提供對材料電子結構的自由度，將有助於材料新穎性質的實現與調控。此外，在此人工堆疊型的研究中，能發現許多新穎的電子結構及二維晶體的層間耦合現象，將石墨基板的特殊一維超晶格電子結構，成功引入堆疊二維晶體的電子結構中，實現二維半導體之電子結構的創新調控技術。

In this thesis, electronic structures of the stacked monolayer two-dimensional (2D) semiconductors are artificially constructed to study their electronic structures at atomic scale by ultra-high vacuum scanning tunneling microscopy and spectroscopy (UHV STM/STS). In the twisted 2D lattice, electronic superlattice (Moiré pattern) is successfully observed and related novel phenomena is discussed.
In this study, chemical vapor deposition (CVD) synthesized monolayer of the MoS2 is selected as representative 2D semiconductor for further studies on the stacked 2D system. With successful control of ultraclean transfer and monolayer manipulation, various stacking of the stacked 2D is achieved for realizing diverse electronic Moiré superstructures, which is an ideal platform for the study of electronic structure of artificial 2D lattice and their interlayer interactions. Atomically resolved STM images confirms high surface and interfacial quality of the transferred monolayers.
Multiple Moiré of different stacking angles and specific stacking configurations are observed and characterized by STM imaging. The modulated periodic potential of Moiré patterns offers an extra degree of freedom for the tailoring of electronic structure Moreover, characteristic electronic structure originating from underlying 1D-superlattice in highly oriented pyrolytic graphite (HOPG) substrate was successfully introduced into the coupled electronic structure of top 2D material. The result of artificial modulation of 2D-material electronic structure is demonstrated for the first time.

Abstract
摘要
誌謝
目錄
第一章 簡介-----1
1-1 緒論-----1
1-2 二維晶體及過渡金屬硫屬化物（TMDs）-----3
1-2-1 晶體結構-----3
1-2-2 電子(能帶)結構-----5
1-2-3 光學性質-----7
1-3 單層過渡金屬硫屬化物（TMDs）之製備-----8
1-3-1 機械剝離法-----8
1-3-2 液相離子插層法-----9
1-3-4 化學氣相沉積法-----10
1-4 二維材料之堆疊-----11
1-4-1垂直式堆疊-----11
1-4-2堆疊二維材料的製程及相關技術-----13
1-5堆疊二維晶體的電子結構之檢測-----16
1-5-1超高真空之掃描穿隧顯微術-----16
1-5-2 堆疊二維晶體之莫瑞圖紋與其調控（Moiré Pattern）-----18
第二章 實驗方法-----23
2-1以化學氣相沉積法合成單層二硫化鉬-----23
2-1-1 試片處理-----23
2-1-2 二硫化鉬的化學氣相合成法-----24
2-2 單層二硫化鉬的轉移-----26
2-2-1 水媒介轉移-----26
2-2-2 聚二甲基矽氧烷（PDMS）輔助轉移-----28
2-3 垂直堆疊二硫化鉬之製程-----30
2-4 材料分析與量測-----32
2-4-1 光學顯微鏡-----32
2-4-2 光致發光光譜-----32
2-4-3 拉曼光譜儀-----33
2-5 掃描式穿隧電子顯微鏡/能譜（STM/STS）-----34
2-5-1 原子解析之表面結構-----34
2-5-2 掃描式穿隧電子能譜-----34
2-5-3 探針之製備-----35
2-5-4 STM 影像結果之分析-----36
第三章 結果與討論-----37
3-1 垂直堆疊單層二硫化鉬之電子結構-----37
3-1-1化學合成大面積二硫化鉬之轉移-----37
3-1-2 單層二硫化鉬之原子結構及電子結構-----39
3-1-3 堆疊二硫化鉬之電子結構及莫瑞圖紋-----43
3-1-4 不同層數於二硫化鉬電子結構之變化-----49
3-1-5 結論-----50
3-2 人工堆疊二維晶體之新穎現象及莫瑞圖紋-----51
3-2-1 以轉移裂痕創造同質堆疊介面-----51
3-2-2 角度比較與實際之莫瑞圖紋-----53
3-2-3 二維晶體邊緣態之掩埋效應（Buried edge state）-----57
3-2-4 二維晶體電子結構隨層數變化與邊界效應-----60
3-2-5 結論-----61
3-3 以層間耦合效應調控二維半導體的電子結構-----62
3-3-1 堆疊二維晶體之表面形貌及電子結構-----62
3-3-2 相異二維晶體堆疊之莫瑞圖紋差異-----64
3-3-3 耦合電子結構之空間分布及偏壓效應-----68
3-3-4 結論-----71
第四章 結論-----72
參考文獻-----73

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