二維材料在過去二十年以來發展迅速，非常有潛力成為下個世代的主流半導體材料，但二維半導體受限於其原生的材料特性，相比於三維矽半導體，二維材料難以進行摻雜且存在金半接觸的費米釘扎等問題，導致其電晶體效能被嚴重的限制，在本論文中，分別提出了兩個方法改善了上述的問題。針對材料的摻雜，我們成功的利用原子擴散的方式將過渡金屬原子與硫族原子置換摻雜；而金半接觸的改良，我們利用氫電漿處理的方式，使接觸區域的二維半導體金屬化，強化過渡金屬與電極金屬的耦合，提升了載子的注入效率，成功地讓金半接面由蕭基接觸特性轉為歐姆接觸特性，等效降低了接觸電阻，提升電晶體的效能。

Over the past decade, the two-dimensional (2D) layered materials have surged and been expected to become the next generation semiconductor materials. But there exist two main problems for 2D materials: One is the doping issue, compared with silicon semiconductor, we can not use ion implantation due to its atomic structure properties. Here we propose a method for site-selective doping to achieve substitutional doping in 2D material. The other is the metal/semiconductor contact issue, we use hydrogen plasma treatment to make the contact area metallization, increases the coupling between transition metal and electrode metal, which can improve the carrier injection efficiency and successfully boost the performance of 2D FET.

第1 章 緒論..... 1
1.1 近代半導體沿革..... 1
1.2 傳統半導體的發展限制..... 3
1.3 二維半導體材料的發展..... 6
1.4 論文架構..... 9
第2 章 二維材料介紹..... 10
2.1 過渡金屬二硫族化合物介紹..... 10
2.1.1 晶體結構..... 10
2.1.2 電子能帶.....13
2.2 石墨烯介紹..... 16
2.2.1 晶體結構..... 16
第3 章 材料製備與檢測..... 18
3.1 化學氣相沉積法..... 18
3.2 二硒化鎢..... 20
3.3 二硫化鎢..... 23
3.4 石墨烯..... 26
3.5 拉曼光譜儀檢測..... 29
3.6 光致螢光光譜儀檢測..... 36
第4 章 原子置換與分析..... 39
4.1 過渡金屬次原子層之置換...... 39
4.2 拉曼光譜儀與光致螢光光譜儀分析..... 49
第5 章 鎢系二維半導體之Janus 結構與分析..... 55
5.1 實驗設備..... 56
5.2 實驗流程與參數...... 57
5.3 拉曼光譜儀與光致螢光光譜儀分析...... 57
5.4 鎢系二維半導體之金半接觸特性..... 62
第6 章 結論與未來展望..... 71
參考文獻..... 72

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