本研究旨在探討於摻雜釩（Vanadium, V）濃度下，不同層數之二硒化鎢（Tungsten Diselenide, WSe2）樣品的電傳輸特性。隨著二維材料在奈米電子領域的應用日益廣泛，摻雜技術已成為調控其能帶結構與載子濃度、進而提升元件效能的重要手段。

本實驗研究採用化學氣相傳輸法（Chemical Vapor Transport, CVT）合成釩摻雜之 WSe2 塊材晶體，透過此方法可有效將釩原子引入 WSe2 晶格中，形成具摻雜不均勻性的 V-WSe2 單晶。經機械剝離後，獲得包含單層、雙層與三層等少數層數的薄片。

利用乾式轉移技術（dry pick-up and transfer）將剝離後的薄片精確轉移至預先設有對位標記之矽基板上，以利後續電子束微影製程的定位。樣品轉移完成後，透過能量散射 X 光譜儀（Energy-Dispersive X-ray Spectroscopy, EDS）分析其元素組成，並搭配原子力顯微鏡（Atomic Force Microscope, AFM）進行非破壞式檢測，以確認樣品的厚度與表面品質，進而建立其物理結構與電性之間的對應關係。

隨後進行半導體製程以製作霍爾棒（Hall bar）結構，包含光阻旋塗、曝光、顯影、金屬蒸鍍與舉離等標準製程步驟，並於樣品上六個端點蒸鍍金屬電極以確保良好接觸。完成之元件透過低維材料電性量測平台進行載子遷移率、霍爾效應與 I-V 特性分析，觀察摻雜後樣品在不同層數條件下其電傳輸行為的變化。

This study investigates the electrical transport properties of vanadium-doped tungsten diselenide (WSe2) with varying layer numbers under a fixed doping concentration. As two-dimensional materials gain prominence in nanoelectronics, doping techniques serve as a key strategy to tune their band structures and carrier concentrations. V-doped WSe2 single crystals were synthesized via chemical vapor transport (CVT) and exfoliated to obtain mono-, bi-, and trilayer flakes. These flakes were transferred onto silicon substrates using a dry pick-up method. Atomic force microscopy (AFM) and energy-dispersive X-ray spectroscopy (EDS) were used to characterize flake thickness and elemental composition. Hall bar devices were fabricated using standard lithographic and metallization processes. Electrical measurements, including two- and four-point probe analyses, were performed to extract carrier mobility, carrier concentrations, and I-V characteristics. The results highlight a layer-dependent transport behavior, with bilayer samples exhibiting improved gate control and higher on-state current compared to trilayers. This work provides insights into the interplay between doping and thickness in 2D materials, offering guidance for future electronic device design.

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