過渡金屬二硫族化物 (Transition-metal Dichalcogenides, TMDCs) 多為層狀材料，由於可以單層狀態穩定存在於環境，並且具有多樣的導電特性，如絕緣體、半導體甚至是超導等。其中最引人注目的半導體性 TMDCs，如 P 型 WSe2 與 N 型 MoS2，天生自帶的摻雜特性與僅 0.7 nm 的厚度，非常有潛力成為下個世代的通道材料。其他塊材材料如矽與三五族半導體在材料厚度降至個位數奈米時，都面臨極為嚴重的特性衰退，而本身可以單層存在的 TMDCs 可以對抗因厚度降低造成的衰退問題。
本論文以化學氣相沉積的 WSe2 作為研究題材，並採用傳輸線模型與四點探針法來分析 WSe2 品質與金屬接觸特性。並依據文獻模擬的接觸金屬特性來設計實驗，並搭配金屬接觸下 WSe2 圖紋化，再依不同圖紋化及不同接觸金屬搭配組合來分析帶來的改變。並證實以 Schottky Mott Rule 推估的蕭特基能障不再適用，以及金屬與 WSe2
接觸後可能帶來的影響。以點狀邊界圖紋化搭配鉻金接觸的 WSe2 電晶體可以得到最大電流約 1.1 µA/µm 與載子遷移率 µ = 3.4 cm2/V· s；與未作圖紋化的鉻金接觸 WSe2 電晶體相比電流提升 120 倍與最佳載子遷移率上升 10 倍。

Transition-metal Dichalcogenides (TMDCs) is a category of layered material whose monolayer is stable in ambient and with diverse conducting properties from insulator to
superconductor. Among the TMDCs, semiconducting ones are the most intriguing, such as P-type WSe2 and N-type MoS2. The inherent doping and the thickness of monolayer could down to 0.7 nm which is promising to be the channel candidate of next node.
We focused on CVD WSe2 and adopted Transmission Line Model (TLM) and 4 port measurement to analysis WSe2 thin film quality and its metal contact properties. Utilizing
simulation results and data from aforementioned TLM to set up our experiment. We composed contact area pattering and different contact metal to confirm our predictions. The intuitively predicted Schottky barrier height by Schottky Mott Rule is no more held.
We obtained remarkable enhancement in the case of dot patterned WSe2 along with Cr/Au contact. Maximum current recorded 1.1 µA/µm and mobility equaled to 3.4 cm2/V· s. The current increased by 120 times and best mobility improved by 10 times both compared to pristine WSe2 with same contact metal.

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