過渡金屬硫族化物 (Transition -metal dichalcogenides, TMDCs)為二維層狀材料，可以單層穩定存在於環境中，而由於費米能階釘札的效應，金屬半導體接觸的好壞對元件效能的影響很大，而電子束微影被廣泛利用在製作元件電極中，然而電子束微影的過程中，電子束不可避免的會透過PMMA電子阻影響到所使用的通道材料，造成通道材料產生缺陷可能加強費米能階釘札的效應，為了探討電子束微影對金屬半導體接觸的影響，我們以二硫化鎢及二硒化鎢為通道材料製作了三種不同製程的金屬半導體接觸，分別是石墨烯接觸、光學微影及電子束微影的電晶體，並透過低溫量測探討其金屬半導體接觸特性，發現其會造成臨界電壓往正端偏移及次臨界擺幅的下降。

Electrical metal contact to two-dimensional material is crucial to device performance due to strong fermi level pinning. Since material may be damaged by electron beam lithography during the process, we try to look into how electron beam affect the material. By adding the area dose, electron beam might cause more defects on the material which cause fermi level pinning. We investigate how electron beam damage the material by comparing the transfer characteristic of Tungsten Diselenide and Tungsten Disulfide field effect transistor using photolithography and electron beam lithography with different area dose respectively.

Abstract...I
論文摘要...II
目 錄 ...IV
第一章 緒論...1
1.1 半導體技術的演變 ...1
1.2 矽製程的微縮與限制 ...3
1.3 低維材料的發展...5
1.4 論文結構...8
第二章 過渡金屬二硫族化物介紹...9
2.1 過渡金屬二硫族化物的組成...9
2.2 過渡金屬二硫族化物的特性...10
2.2.1 晶體結構 ...10
2.2.2 電子能帶... 12
2.3 過渡金屬二硫族化物材料製備方法...14
2.3.1 機械剝離法 (Mechanical exfoliation)...15
2.3.2 化學氣相沉積法 (Chemical vapor deposition)...15
2.4 材料檢測方式...17
2.4.1 拉曼散射頻譜...17
2.4.2 光致螢光光譜...20
第三章 半導體材料與金屬接觸探討...22
3.1 傳統塊材半導體之金屬接觸特性...22
3.2 過渡金屬硫族化物之金屬接觸特性...29
3.2.1 過渡金屬硫族化物與金屬接觸機制...29
3.2.2 接觸金屬與費米能階釘扎問題...31
3.2.3 電子束對過渡金屬硫族化物的影響...35
第四章 元件製程及材料檢測...38
4.1 材料成長與檢測...38
4.1.1 二硒化鎢及二硫化鎢成長...38
4.1.2 石墨烯成長...41
4.1.3 光致螢光光譜檢測...45
4.2 元件製作流程...45
第五章 實驗量測與結果分析...53
5.1 電晶體量測方法與量測系統...53
5.2 電晶體電性量測結果與分析...54
5.3 電晶體變溫量測結果與分析...59
第六章 實驗結果與未來展望...69
參考文獻...70

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