過渡金屬二硫族化物（Transition-metal dichalcgenides,TMDCs）為二維層狀材料 具有多樣的特性，不管是在電性，光學，物理及化學特性都有很好的表現 ，且導電特性上更可以分為絕緣性、半導體性、類金屬性。而在金屬與半導體的接觸特性一直是一個眾所皆會討論的重要議題，有別於一般傳統的上端接觸結構(Top-bonded contact structure)有較大的接觸電阻及較差的載子注入，在此本論文將探討一個較小的接觸電阻及更有效的載流子注入方法。因此提出了末端接觸結構(End-bonded contact structure)的設計，在金屬與半導體上有更短的接觸鍵結，更多的軌域混成。 預先度上Pt / Ti的晶種層(Seeding layer) 再經由化學氣相沉積(Chemical vapor deposition,CVD)的方式形成末端接觸結構。 WS2場效電晶體的電性表現， 電流密度可達到76.85 uA/um，載子遷移率為43.92 cm2 / Vs。次臨限擺幅 = 149 mV/dec，開關比約為103，蕭特基 能障272 meV接勝過同一通道上的上端接觸結構。而末端與上端接觸結構兩者的蕭特機能帳障高度差將影響整體元件特性，MIT的現象也在WS2元件傳輸特性被觀察到。

Transition-metal dichalcogenides (TMDCs) are two-dimensional layered materials with various properties, which are excellent in electrical, optical, physical and chemical properties, and have better electrical conductivity. It can be classified into insulating, semiconducting, and metallic. The contact characteristics between metal and semiconductor have always been an important topic that everyone will
discuss. Different from the traditional top-bond contact structure, there is a large contact resistance and poor carrier injection. This paper will explore a smaller contact resistance and a more efficient method of carrier injection. Therefore, an end-bond contact structure has been proposed, which has shorter contact bonding between metal and semiconductor. More orbital mixes. A seed layer of Pt/Ti is
preliminarily formed and a terminal contact structure is formed by chemical vapor deposition (CVD). The electrical performance of WS2 field effect transistor, the current density can reach 76.85 A/m, and the carrier mobility is 43.92 cm2/Vs.The subthreshold swing = 149mV/dec, the switch ratio is about 103, and the Schottky
barrier 272 meV wins over the upper contact structure of the same channel.The difference in the height of the Schottky barrier between the end and the upper contact structure will affect the overall component characteristics, and the MIT phenomenon is also observed in the WS2 component transmission characteristics.

Abstract---II
論文摘要---III
目錄---IV
第一章序論---1
1.1 半導體技術演進史---1
1.2 傳統半導體發展的侷限---2
1.3 二為半導體材料---3
1.4 低維度半導體的侷限---4
1.5 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之組合與晶型結構---9
2.2 過渡金屬二硫族化物之電子能帶結構---11
2.3 過渡金屬二硫族化物材料製備方法---13
2.3.1機械剝離法(Mechanical exfoliation)---13
2.3.2 化學氣相沉積法(Chemical vapor deposition)---14
2.4 二硒化鎢與二硫化鎢材料檢測方式---18
2.4.1 拉曼散射頻譜---18
2.4.2 光致螢光光譜---20
第三章過渡金屬二硫族化物與金屬接面特性---23
3.1 費米能階釘札與接觸金屬的探討---23
3.2 過渡金屬二硫族化物與金屬接面探討---25
3.3 接觸電阻改善之方式---28
3.4 蕭特機能障分析探討---31
第四章元件製程與材料分析檢測---35
4.1末端金屬化接觸電極---35
4.2 二硫化鎢材料成長---37
4.3 上端接觸金屬電極---42
4.4 二硫化鎢材料檢測---43
4.4.1 拉曼散射頻譜---43
4.4.2 光致螢光光譜---44
4.5 離子液體上閘極---45
第五章實驗量測結果與分析---49
5.1 元件結構介紹---49
5.2 元件量測方法與量測系統---50
5.3 元件量測結果分析---51
5.3.1 二硫化鎢電晶體量測結果分析---51
5.3.2 二硫化鎢電晶體變溫量測結果分析---59
5.3.3 二硫化鎢傳輸特性探討---62
第六章結論與未來展望---66
6.1 實驗總結與未來展望---66
參考文獻---67

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