近年來，過渡金屬二硫化物因其具有半導體特性、可調遷移率和可撓性等特性而引起了廣泛的關注。為了提供大規模商業生產，有效控制生長參數將是實現大尺寸和層數可調控之二維材料的關鍵。本次研究中，我們嘗試使用氯化鈉作為促進劑，通過化學氣相沉積法在二氧化矽基板上直接生長單晶二硫化鉬二維材料。藉由調控氯化鈉含量以及硫粉溫度等生長條件，可以有效生長單層二硫化鉬單晶，且最大尺寸可達109 μm。經由拉曼、光致發光光譜與原子力顯微鏡證實為單層二硫化鉬。此外，本研究也進一步將已生長的單晶二硫化鉬利用水轉移到預鍍電極之二氧化矽基板上，以製造場效電晶體元件。量測結果顯示二硫化鉬為n型半導體行為，室溫下開關電流比為104，而電子遷移率為0.5 cm2/V-s。本研究提供以氯化鈉作為二硫化鉬二維半導體材料生長之促進劑，以生長可控且大面積之二維材料。

In recent years, transition metal dichalcogenides (TMD) have attracted significant attention due to their semiconducting properties, tunable mobility, and flexibility. To enable large-scale commercial production, effective control of growth parameters is crucial for achieving controllable two-dimensional (2D) materials with large size and layer control. In this study, we attempted to use sodium chloride (NaCl) as a promoter to directly grow 2D single-crystalline molybdenum disulfide (MoS2) materials on a silicon dioxide (SiO2) substrate through chemical vapor deposition (CVD). By controlling the NaCl content and sulfur powder temperature, we successfully grew monolayer to few-layer MoS2 with size up to 109 μm. The layer number of MoS2 was confirmed through Raman spectroscopy, photoluminescence (PL) spectroscopy, and atomic force microscopy (AFM). Furthermore, the grown single-crystalline MoS2 was transferred onto a pre-patterned SiO2 substrate to fabricate field-effect transistor (FET) devices. The measurements revealed n-type semiconductor behavior for MoS2 with a room-temperature field-effect mobility of 0.5 cm²/V-s. This study provides a method for the controllable growth of large-area 2D materials using NaCl as a promoter for the growth of MoS2 as a 2D semiconducting material.

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