單層石墨烯被發現以來，二維材料在研究及發展上獲得相當大的關注。其中，從結構的觀點，二維材料由多層的原子厚度之平面結構組成，而層與層之間為較弱的凡德瓦（Van der Waals）鍵結，使各單層在結構維持相當程度的本徵特性；從材料特性的觀點，二維材料涵蓋廣闊，包括:半金屬的石墨烯，半導體的過渡金屬二硫屬化物（TMDCs）、黑磷，絕緣體的氮化硼…等等，由此衍生的介面結構十分新穎，而相關的光學、電性和結構等研究亦蓬勃地發展。但可惜的是介面的能帶結構無法從這些研究中被清楚地了解，又能帶結構對半導體元件的設計與應用非常重要。因此，二維材料在介面的能帶結構是近期的研究重點。
而本文即以二維材料組成之異質介面的能帶結構為重點，並在國家同步輻射中心（NSRRC）利用掃描式光電子能譜顯微術（SPEM），進行（1）石墨烯與氧化鋅(Graphene/ZnO)異質介面，（2）二硫化鉬與二硫化鎢(MoS2/WS2)異質介面，兩個主題的能帶結構研究。並由主題（1）的結果，發現由原子層沉積（ALD）成長氧化鋅薄膜在不同層數石墨烯覆蓋形成的介面中，氧化鋅薄膜在介面維持著平帶（flat band）的能帶特性。又此與文獻，石墨烯和單晶氧化鋅形成蕭特基（Schottky）接面的電性量測結果相當不同。另外，主題（2）比較由兩種不同的鍵結方式（凡德瓦鍵、共價鍵）形成之異質介面，發現兩種介面的能帶結構有著截然不同的特性，若以此作為應用基礎，相信對二維結構在半導體元件的開發上有所貢獻。

關鍵字: 二維材料、能帶結構、光電子能譜、石墨烯、過渡金屬二硫屬化物

In this study, we focus on 2D material interface and measured the band structure by Scanning Photo-Electron Microscopy (SPEM) at National Synchrotron Radiation Research Center (NSRRC). The experiment with two topics: (1) Graphene/ZnO heterojunction, and (2) MoS2/WS2 heterostructures. From the topic (1), we found ZnO with flat band structure contact to the interface, and it was quite different from the results of Schottky contact in literature. In topic (2), we compared two MoS2/WS2 hetero- structures with different bonding at the interface (Van der Waals bond and covalent bond), and we found the structures have distinct band structure properties. With these new results, we believe it will contribute to the application of two-dimensional materials in the future.

Keywords: 2D material, band structure, X-ray photoelectron spectroscopy, graphene, transition-metal dichalcogenide

摘要 I
Abstract II
致謝 III
目錄 V
圖目錄 VIII
表目錄 XI
第一章 緒論 1
1.1前言 1
1.2研究動機 4
第二章 文獻回顧 5
2.1石墨烯異質介面 5
2.1.1石墨烯之特性簡介 5
2.1.2石墨烯/氧化鋅(Graphene/ZnO)異質介面 9
2.2 TMDCs異質結構 11
2.2.1 TMDCs之特性簡介 11
2.2.2 TMDCs之垂直堆疊(Vertical stacking)異質結構 14
2.2.3 TMDCs之橫向成長(Lateral growth)異質結構 20
第三章 實驗原理及分析方法 23
3.1同步輻射光源(Synchrotron Radiation Light Source) 23
3.1.1同步輻射簡介 23
3.1.2同步輻射與傳統X光光源比較 25
3.2 X光光電子能譜術(X-ray Photoemission Spectroscopy; XPS) 27
3.3掃描式光電子顯微術(Scanning Photoelectron Microscopy; SPEM) 33
3.4拉曼光譜(Raman Spectrum) 35
3.5 光激發螢光光譜(Photoluminescence Spectrum) 36
第四章 Graphene/ZnO異質介面之能帶結構 38
4.1 樣品設計與製備 38
4.2拉曼光譜分析 42
4.3 光電子能譜分析 44
4.4 Graphene/ZnO介面-能帶圖(Band Diagram) 49
第五章 MoS2/WS2異質介面之能帶結構 50
5.1樣品設計與研究方法 50
5.2 MoS2/WS2之垂直堆疊(Vertical stacking)異質結構 52
5.2.1螢光光譜分析 52
5.2.2光電子能譜分析 53
5.2.3 MoS2/WS2之垂直堆疊異質結構-能帶圖(Band Diagram) 58
5.3 MoS2/WS2之橫向成長(Lateral growth)異質結構 60
5.3.1螢光光譜分析 60
5.3.2光電子能譜分析 61
5.3.3 MoS2/WS2之側向成長異質結構-能帶圖(Band Diagram) 65
5.4垂直堆疊與橫向成長異質結構之比較 66
第六章 總結 67
第七章 參考文獻 69

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