在本論文中，我們探討不同真空度下以過渡金屬硫化法成長均勻且大面積的過渡金屬硫化物薄膜，同時利用了濺鍍時間的改變、建立出二維材料層數及 ∆k 值的對應關係。並在原先使用低功率氧電漿進行原子層蝕刻的技術基礎上，以原子力顯微鏡測量出二硫化鉬對於二硫化鉬、鉬氧化物及藍寶石基板之吸附力強弱，得出原子層蝕刻之機制。之後我們將薄膜應用於上閘極場效電晶體，由並透過電晶體的特性來進行氧化層的最佳化。在氧化層最佳化的過程中發現高溫之氧化層成長製程可以於二硫化鉬與氧化層接面產生氧化鉬，其可幫助電子傳遞，提升電晶體之特性。再以熱退火處理來提升氧化層之品質並幫助氧化鉬生成，持續提升電晶體特性。於此同時將原子層蝕刻技術導入電晶體製程中，以改變源極與汲極下方不同層數、不同接觸面積之二硫化鉬薄膜。並發現完全接觸之元件，其金屬與二硫化鉬之蕭基能障，能夠迫使更多的電子進入通道中，因此擁有較小之截止電壓。而當閘極電壓大於8伏時，由於金屬與材料接面上持續累積的電子達到飽和，加上空乏區的退縮，致使累積的電子會開始沿著二硫化鉬之表面形成接面電流。使得原本應該進入飽和區之 ID-VDS 持續的增加。為了更進一步增加電晶體特性，將銻烯此金屬性二維材料電極與異質結構也加入元件製程。利用銻烯與二硫化鉬之間具備低接觸電阻；異質結構會形成類似 Type-II 的能帶結構等特性，使二硫化鉬通道獲得更多的載子注入，以達元件特性之提升。

In this work, we grow large-area transition metal dichalcogenide films with different approaches. We have also investigated the mechanism of atomic layer etching by using the low-power oxygen plasma. We optimize the growth of the dielectric layer through the fabrication of top-gate MoS2 transistors. During alter the different layer numbers and area which underneath the source and drain electrodes could have the higher on current and lower threshold voltage. To enhance the on current of the device, both the metallic 2-D material and hetero-structures also be used into the transistor fabrication.

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