本研究論文是以化學氣相傳導法利用碘 (I2) 為傳導劑成長鉬鎢輕摻雜之二硫化鉬鎢 (Mo1-xWxS2, 0 ≤ x ≤ 0.1; 0.9 ≤ x ≤ 1, Δx = 0.02) 系列層狀單晶半導體，並且對此系列晶體之光學特性進行量測與激子能量彎曲效應 (Bowing effect) 研究。藉由X-ray 繞射與Raman量測分析可確定此系列晶體之結構為2H (Two-layer Hexagonal) ，並且探討鉬 (Mo) 和鎢 (W) 之輕摻雜比例改變後其晶體結構及光學性質的變化，同時可定義晶體的成分比例變化。 在光學量測實驗，利用壓電調制反射光譜 (PzR) 可確定Mo1-xWxS2系列晶體之激子A1與B躍遷訊號，在室溫的情況下，其激子躍遷訊號隨成分變化之範圍分別在1.85~1.98 eV及2.05~2.41 eV之間。此外，Mo1-xWxS2藉由鉬與鎢之輕摻雜發現PzR的激子能量的隨成分變化而具有彎曲效應的現象。根據上述現象，藉此研究探討過渡性金屬元素對導帶底部會產生彎曲效應的影響，並且由激子躍遷訊號對成份變化的擬合結果可得知Mo1-xWxS2系列晶體中激子躍遷訊號最低的位置約在x=0.2，研究出彎曲效應對激子躍遷訊號變化的影響。

Layered crystals of Mo1-xWxS2 (0 ≤ x ≤ 0.1; 0.9 ≤ x ≤ 1, Δx = 0.02 ) have been grown by chemical vapor transport (CVT) method using iodine as a transport agent. Detailed characterization of the materials are carried out by using X-ray diffraction (XRD), Raman scattering and piezoreflectance (PzR) techniques. XRD analysis and Raman scattering measurement confirm that Mo1-xWxS2 crystals are crystallized in two-layer hexagonal structure. Optical properties of Mo1-xWxS2 were characterized using PzR measurement which showed that the excitonic transition energies A1 of Mo1-xWxS2 varied in the range of 1.85-1.98 eV and B is of 2.05-2.41 eV at room temperature. In addition, the PzR results reveal that the bowing effect existed in the composition-dependent excitonic transitions of Mo1−xWxS2 alloys with dilute Mo and W incorporations. The excitonic transitions of the excitons A1 and B show different value of bowing parameter. According to the experiment observations, this study have demonstrated excitons transitions A1 and B are different in bowing effect. The result showed the excitonic transitions energies are tunable by doping effect.

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