層狀單晶半導體Mo1-xWxSe2屬於過渡性金屬雙硫屬化合物(Transition-metal-dichalcogenides) 簡稱TMDCs，層與層之間僅有微弱的凡得瓦爾作用力 (Van der waals force) 。
本論文利用化學氣相傳導法 (Chemical vapor transport method) 以溴或碘 (Br2 or I2) 為傳導劑成長三元化合物Mo1-xWxSe2。利用電子顯微鏡上的能量散佈分析儀 (EDS) 來確認樣品元素的比例；並藉由X光繞射量測 (XRD) 分析樣品的晶格結構，計算出晶格常數隨著成分的變化；以氬氣雷射 (Ar+) 為激發源量測拉曼散射光譜 (Raman scattering spectra) 可以得到一階拉曼模態 與 ，使用Modified random-element isodisplacement (MREI) model作理論計算且作數據擬合可得各模態的力學常數 (Force constant) 。
在光學方面，使用壓電調制反射光譜技術量測直接能隙附近的激子A1與激子B之躍遷能量，探討隨著激子躍遷的訊號隨著成份的變化，並對溫度與激子躍遷訊號和展寬變化的關係加以討論。

Molybdenum Tungsten diselenides (Mo1-xWxSe2) belong to the group VIA layer type transition metal dichalcogenides, grown by the chemical vapor transport method using Bromine (Br2) or Iodine (I2) as a transport agent. Energy dispersive X-ray spectroscopy (EDS) has been employed to determine the contents for Molybdenum Tungsten diselenides (Mo1-xWxSe2) . By analyzing the X-ray diffraction patterns, the structure of Mo1-xWxSe2 (0 x 1) remains the 2H symmetry. Raman scattering for first-order and modes have been observed in the range of 150-300 cm-1, Modified random-element-isodisplacement (MREI) model has been adopted to successfully predict mode behaviors of and modes in Mo1-xWxSe2 alloys. Further, composition-dependent and frequencies can be well fitted by the MREI model, giving composition-dependent force constants.
The temperature dependence of the spectral features in vicinity of the direct band edge of mixed-crystals Mo1-xWxSe2 solid solution is measured in the temperature range of 25-295 K by using piezoreflectance (PzR) . The near band-edge excitonic transition energies of Mo1-xWxSe2 solid solutions were determined accurately from a detailed line-shape fit of PzR spectra. The near band-edge excitonic transition energies and their splittings were found to vary smoothly with the increase of W content x, indicating that the natures of the direct band edges of Mo1-xWxSe2 solid solutions are similar. In addition, the parameters that describe the temperature variation of the energies and broadening function of the excitonic transitions are evaluated and discussed.

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