本論文使用化學氣相傳輸法 (Chemical vapor transport, CVT) 以碘為傳導劑成長W(SxSe1-x)2 (0 ≤ x ≤ 1, Δx = 0.2和x = 0.5) 系列層狀半導體樣品, 並對此系列樣品進行材料分析與光學特性研究. 利用穿透式電子顯微鏡和能量散佈分析儀觀察與分析此系列樣品的晶格結構和元素比例. 藉由X-ray繞射實驗可以確定此系列樣品單晶之晶體為2H六角結構, 並計算其晶格常數. 從Raman光譜分析其晶格振動和聲子分析材料組成結構, 其特徵峰分別為E12g 和A1g , 量測範圍在150 - 450 cm-1. 在光學方面以壓電調制光譜技術來量測並利用壓電陶瓷材料給予樣品週期形態性應變, 在25 K至300 K做變溫量測, 以研究此系列樣品在直接能隙附近之激子躍遷特性與激子能隙結構, 並對量測結果以勞倫茲線形擬合獲得此系列樣品在各溫度下激子躍遷A1和B訊號能量, 探討激子躍遷的訊號隨著硫成份變化, 並對溫度與激子訊號和展寬變化的關係加以討論.

W(SxSe1-x)2 (0 < X < 1, Δx = 0.2 and x = 0.5) series of single crystal were gown by chemical vapor transport method (CVT) using iodine as a transport agent. Energy dispersive X-ray spectroscopy was employed to determine the contents of W(SxSe1-x)2 (0 < X < 1, Δx = 0.2 and x = 0.5). By X-ray diffraction measurement, the structure of W(SxSe1-x)2 serias all had the same 2H two-layer hexagonal structure. The evolution of lattice parameter of W(SxSe1-x)2 was reported in this study. Raman scattering for the first-order E12g and A1g modes were observed in the range of 150 - 450 cm-1. The temperature dependence of the spectral features in the vicinity of the direct band edge of mixed crystal W(SxSe1-x)2 were measured in the temperature range of 25 K - 300 K by using piezoreflectance (PzR). Form a detailed line shape fitting 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 variations of the energies and broadening functions of the excitonic transition was evaluated and discussed.

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