本論文是利用化學氣相傳導法 (Chemical Vapor Transport, CVT) 成長層狀半導體Mo(SxSe1-x)2，其傳導劑為碘 (I2)。從X光繞射實驗可以確定此系列單晶之成分組成及晶體結構，並可計算其晶格常數，發現其晶格常數a為線性變化，但是晶格常數c卻為拋物線變化，而c/a會有一個最大值出現在MoS0.6Se1.4。
　　接著從拉曼散射實驗 (Raman Scattering) 觀察其晶格振動和聲子訊號，並利用MREI模型 (modified random element displacement model) 計算其A1g和E2g振動模態的力學常數，了解此系列樣品的雙模態特性 (two-mode behavior) 。
　　最後從壓電調制反射光譜和一次微分型式的勞倫茲線形公式，可得其能隙附近的兩個激子躍遷訊號與半高寬。發現此系列樣品隨著硫成分變化，其激子訊號的變化是平滑的，這可能是因為硫與硒之間的化學性質是相近的。接著，觀察溫度變化對樣品的影響，並利用Varshni與Bose-Einstein關係式來探究溫度對此系列材料激子躍遷訊號及半高寬的變化。

We used chemical vapor transport (CVT) to grow Mo(SxSe1-x)2 mixed-layered crystals with iodine (I2) as a transport agent. By X-ray diffraction measurement, in the system Mo(SxSe1-x)2, a continuous series all have the same 2H two-layer hexagonal structure (space group P63/mmc) . The evolution of lattice parameter of the mixed-layered system will be reported in this thesis. We find the a parameter and unit-cell volume are both nearly linear with x. The c parameter is parabolic and the c/a ratio shows a clear maximum at x=0.3, correponding to MoS0.6Se1.4.
Lattice vibrations of Mo(SxSe1-x)2 are also measured by Raman spectroscopy in this thesis. The values of force constants can be calculated by MREI-model. The model successfully confirms the two-mode behavior exhibited by the series and the calculated values agree very well with experimentally observed values.
The temperature dependence of the spectral features in the vicinity of the direct band edge of Mo(SxSe1-x)2 is measured in the temperature range of 25-295K by using piezoreflectance (PzR) . From a detailed line shape fit of the PzR spectra, the temperature dependences of energies and broadening parameters of the A1 and B excitons are determined accurately. The parameters that describe the temperature variation of transition energies and broadening parameter of the excitonic transitions are evaluated and discussed.

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