本研究主要探討三硫化鈦的厚度以及表面形貌對其材料特性所造成的影響，讓我們更了解層狀結構材料的基本傳導機制。
首先我們針對利用化學氣相傳輸法合成出的三硫化鈦進行成分與結構的分析，利用光學顯微鏡和掃描式電子顯微鏡觀察材料形貌，透過顯微拉曼光譜儀了解原子振盪模式，最後使用X光繞射儀與穿透式電子顯微鏡得知材料的晶體結構與成分比例。其中，又會使用顯微拉曼光譜儀來特別探討三硫化鈦的線性二色性特徵。
緊接著，在完成元件的製備後，我們會透過變溫電性量測來偵測三硫化鈦導電度與溫度的關係，並因此發現了metal-to-insulator transition ( MIT )的特殊現象。而後我們也量測數個不同厚度的元件，並彙整了導電度與厚度的關聯，進而推導出三硫化鈦表面主導的傳導機制。接著我們更深入探討表面形貌對於電性表現的影響，發現表面的平滑/完整與否，會大幅影響表面原子的集體激發，也就跟著影響polar optical phonon的強弱，於是我們便會在粗糙度較大的元件特性中看到MIT的消失。

In this study, we mainly discuss the influence of thickness and surface morphology on TiS3’s electrical properties and the basic transport mechanism.
First of all, we synthesized TiS3 by chemical vapor transport method. And then optical microscope and scanning electron microscope were utilized to observe the morphology of the material. We also proceeded the Raman and TEM analysis to confirm the atomic vibration modes and the crystal structure of TiS3. Especially, Raman spectroscopy was applied to detect the linear dichroism in TiS3.
After the fabrication of TiS3 devices, the temperature-dependent measurements were conducted to measure the conductivity within different temperature, we therefore explored the metal-to-insulator transition (MIT) in TiS3 during the experiments. After that, thickness-dependent measurements whose results deduced the surface-dominant transport mechanism in TiS3 were followed. Because of this special phenomenon, the effect of surface morphology on TiS3 electrical properties was investigated. We then discover the roughness of devices surfaces will significantly affect the collective excitation of the surface atoms, so-called phonon. The decline of the phonon will hence cause the absence of MIT in TiS3.

摘要.....I
Abstract.....II
致謝.....III
目錄.....IV
圖目錄.....VII
表目錄.....XI
第1章 緒論與文獻回顧.....1
1-1 奈米科技.....1
1-1-1 奈米科技的興起與發展.....1
1-1-2 過渡金屬三硫族化物的崛起.....2
1-2 三硫化鈦 (TiS3).....3
1-2-1 三硫化鈦的基本性質.....3
1-2-2 線性二色性 (Linear Dichroism, LD).....5
1-2-3 三硫化鈦的層數檢測.....6
1-3 三硫化鈦的相關應用.....8
1-3-1 場效電晶體 (Field-Effect Transistor, FET).....8
1-3-2 光偵測器 (Photodetectors).....11
1-3-3 極化光感測器 (Polarized Photosensors).....13
1-3-4 異質結構 (Heterostructures).....14
1-4 層狀材料內的載子散射機制.....16
1-5 研究動機.....20
第2章 實驗步驟與儀器介紹.....21
2-1 實驗步驟.....21
2-1-1 利用化學氣相傳輸法成長三硫化鈦.....22
2-1-2 以機械剝離法與乾式轉印法製備少層數之三硫化鈦.....24
2-1-3 三硫化鈦元件之製備.....26
2-1-4 元件之電性量測.....28
2-2 儀器.....29
2-2-1 單區加熱爐管 (Single Zone Furnace).....29
2-2-2 光學顯微鏡 (Optical Microscope, OM).....30
2-2-3 顯微拉曼光譜儀 (Micro-Raman Spectroscope).....31
2-2-4 X光繞射儀 (X-Ray Diffractometer, XRD).....32
2-2-5 原子力顯微鏡 (Atomic Force Microscope, AFM).....33
2-2-6 掃描式電子顯微鏡 (Scanning Electron Microscope, SEM).....34
2-2-7 穿透式電子顯微鏡 (Transmission Electron Microscope, TEM).....35
2-2-8 X光能量散佈分析儀(Energy Dispersive X-ray Spectrometer, EDS).....36
2-2-9 電子束微影系統 (Electron Beam Lithography).....37
2-2-10 電子束蒸鍍系統 (Electron Beam Evaporator).....38
2-2-11 電性量測系統 (Electrical Property Measurement System).....39
第3章 結果與討論.....40
3-1 三硫化鈦的結構檢測與成分分析.....40
3-1-1 三硫化鈦表面形貌分析.....41
3-1-2 三硫化鈦結構分析.....43
3-1-3 顯微拉曼光譜分析.....45
3-1-4 三硫化鈦的線性二色性.....47
3-2 三硫化鈦電晶體元件電性量測.....49
3-2-1 變溫電性量測.....49
3-2-2 材料厚度與導電性的關係.....54
3-2-3 表面形貌與傳導機制.....58
第4章 結論.....62
第5章 未來展望.....64
參考文獻.....65

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