在這篇論文中，我們研究化學沉積法成長的單層二硫化鎢(WS2)和二
硫化鉬(MoS2)場效電晶體元件的電子傳輸特性與低頻雜訊表現。我們測量單層二硫化鎢和二硫化鉬的電流-電壓曲線得知兩材料皆為N型半導體，同時也由此計算出材料的電子遷移率。單層二硫化鎢和二硫化鉬的電子遷移率分別為1-2 cm2/Vs和30-40 cm2/Vs。單層二硫化鎢電晶體的低頻雜訊行為和在高電子濃度(大於3 × 1013 cm-2)下單層二硫化鉬電晶體的低頻雜訊表現。
低頻雜訊強度與電子濃度的關係可以判斷1/f 雜訊是來自電荷數目
的擾動還是電荷遷移率的擾動。低頻雜訊強度與電子濃度的關係是找出
1/f 雜訊的電流擾動的來源的重要課題。在我們的工作中發現，單層二硫化鎢電晶體的1/f 雜訊雖然γ=1.5不符合Hooge empirical low，但雜訊表現可以判斷此1/f 雜訊可能是源自於電荷遷移率擾動，而單層二硫化鉬電晶體在高電子濃度下的1/f 雜訊是源自於電荷數目的擾動。

In this thesis, we study electrical transport properties and low frequency noise behaviors on chemical-vapor-deposition (CVD) monolayer WS2 and MoS2 FETs devices. We measure the transfer function and the IV characteristics, and N-type semiconducting behaviors of both WS2 and MoS2
are also obtained. The mobility of single-layered WS2 and MoS2 are 1-2 cm2/Vs and 30-40 cm2/Vs, respectively. Moreover, the low-frequency noise behavior of monolayer WS2 FETs is investigated, and low frequency noise performance in high carrier density (above 3 × 1013 cm-2) of monolayer MoS2 FETs is discussed in Chapter 3.
Carrier density dependence of low frequency electrical noise is a way to determine whether the 1/f noise is dominated by fluctuations in carrier number or carrier mobility. Carrier density dependence is an important topic to characterize the source of electrical current fluctuation forming 1/f noise out. Our experimental results show that 1/f noise of CVD single-layer WS2 FETs is dominated by fluctuation of carrier mobility, although γ=1.5 of this WS2 1/f noise deviates from Hooge empirical law, and 1/f noise of CVD single-layer MoS2 FETs at high carrier density regime is dominated by fluctuation of carrier number.

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