本實驗主要研究層狀過渡金屬硫化物Mo1-xWxS2 之光電導特性，利用化學氣相傳導法合成含不同比例(x = 0-1, Δx = 0.1)之Mo1-xWxS2，並分別以拉曼光譜儀、X光能量散佈光譜儀以及X光光電子能譜儀做定性與定量的分析，結果顯示Mo1-xWxS2 之組成比例可以有效地利用莫爾數比計算初始原料的配重來調整。霍爾效應量測結果顯示x比例越高則會形成n摻雜，提高載子濃度；而遷移率則因雜質散射效應的影響而降低，使得電導率隨x 比例變化。我們將Mo1-xWxS2 製作成金屬-半導體-金屬光電導元件，進行雷射光波長為405、532、632.8 及808 nm的光電流量測。不同波長雷射光因其光子能量與吸光度之差異，使得短波長雷射光照射之光響應最好。另外，由於不同x 比例影響Mo1-xWxS2 本身之電導率與吸光度，並且產生了能隙彎曲效應(Bowing effect)，使得Mo0.6W0.4S2 光電導特性最佳，Mo0.3W0.7S2 光電導特性最差。除此之外，當x比例為0.7-1 時，材料特性轉為由WS2 主導，儘管WS2 之吸光度較小且能隙較大使其不利於光電流的產生，但由於其高電導率與較長載子生命週期等性質仍使得其光電導特性優良。

In this thesis, we investigated the photoconductive characteristics of the transition metal dichalcogenide Mo1-xWxS2 synthesized by chemical vapor transport method with different proportion of x (x = 0-1, Δx = 0.1). Raman spectroscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy were used to analyze the qualitative and quantitative characteristics of Mo1-xWxS2. The results showed that the composition proportion of Mo1-xWxS2 can be tunable effectively by calculating the mole number ratio of the starting materials. The result of Hall effect measurement represented that the concentration of carrier was increased with increasing x. However, the mobility was decreased with increasing x because of the impurity scattering effect, which makes the conductivity of Mo1-xWxS2 varied with the proportion of x. We also made the Mo1-xWxS2 into metal-semiconductor-metal photoconductive detectors and then processed the measurement of photocurrent under different wavelength of laser sources, which were 405, 532, 632.8 and 808 nm. Since different wavelength of laser sources have different phonon energies and absorbances, the shorter wavelength presents better photoresponse. Moreover, the proportion of x influenced the conductivity and absorbance of Mo1-xWxS2 and induced the energy gap bowing effect, making the Mo0.6W0.4S2 had the best photoconductive characteristic and the Mo0.3W0.7S2 had the worst photoconductive characteristic. Besides, the material characteristics of the proportion of x between 0.8 and 1 were controlled by WS2. Although the WS2 had smaller absorbance and the higher energy gap, which were unfavorable to generate photocurrent, the excellent electrical properties of WS2 resulted in good photoconductive charac

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