本論文利用化學氣相傳導法（Chemical Vapor Transport method，CVT）成長硫化鉍系列晶體，藉由使用不同傳導劑三氯化碘或碘成功成長出Bi2S3和(Bi(Bi2S3)9I3)0.667半導體單晶，並對此系列晶體進行結構分析，也藉由光學及電學量測對其特性加以研究討論。
利用能量散佈光譜分析儀（Energy dispersive X-ray spectroscopy，EDS）驗證化合物組成比例，以X-ray晶格繞射（X-ray diffraction，XRD）及穿透式電子顯微鏡（Transmission electron microscopy，TEM）分析結果得到Bi2S3為正交晶系結構，而(Bi(Bi2S3)9I3)0.667則為六方晶系，且兩者晶體品質皆良好，並藉由拉曼光譜量測，得知材料中結構訊息與聲子之振動模式。
經由光穿透實驗及溫度變化之暗電導量測，可以得知Bi2S3為退化型半導體，其具有能隙並呈現近金屬性的載子傳導行為。六方(Bi(Bi2S3)9I3)0.667在電導率溫度相依呈現半導體的傳導行為，此結果可以推論在硫化鉍化合物中摻入碘可以降低硫空缺進而減少載子濃度。此外，由熱探針法可分辨半導體型別，結果顯示Bi2S3為n型半導體，而(Bi(Bi2S3)9I3)0.667為p型半導體。在10 K至300 K之 Seebeck係數、電阻率及熱導率溫度相依實驗，可以發現Bi2S3微具熱電效應，在300 K時Seebeck係數可達最強約-55.520 µV/K。
此外，藉由擬合(Bi(Bi2S3)9I3)0.667吸收係數隨溫度變化之譜線，可以確定此材料為間接能隙半導體，其間接能隙於300 K時約在0.73±0.03 eV，於30 K時約在0.93±0.03 eV。在(Bi(Bi2S3)9I3)0.667熱調製實驗結果，可以發現在300 K時有一帶間躍遷訊號E1在1.08 eV，在40 K時帶間躍遷訊號E1位移至1.18 eV，且在0.98 eV有缺陷訊號。由照射不同燈源光譜之I-V量測結果顯示其在近紅外光響應較佳，可推測其具有太陽能源材料方面的應用潛力。

Bi2S3 and (Bi(Bi2S3)9I3)0.667 single crystal were successfully grown by chemical vapor transport method using ICl3 or I2 as the transport agent. We use X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy to analyze structure and crystal quality of the materials. Energy dispersive X-ray spectrometer (EDS) measurement result shows the composition ratio of the crystal. According to the experimental results, the Bi2S3 crystal crystallizes in orthorombic structure, and (Bi(Bi2S3)9I3)0.667 crystal is hexagonal structure.
In combination of transmittance and temperature-dependent conductivity measurements confirmed that the Bi2S3 is a degenerate semiconductor. It shows not only energy gap but also metallic transport behavior. The origin of such metallic conduction may stem from a substoichiometry of sulfur whereby the sulfur vacancies serve as the source of conduction carriers. The (Bi(Bi2S3)9I3)0.667 exhibits semiconducting transport behavior which is evident from in temperature-dependent conductivity measurements. The hot-probe test confirms the Bi2S3 is an n-type semiconductor while (Bi(Bi2S3)9I3)0.667 is a p-type semiconductor.
Temperature dependence of Seebeck coefficient S, electrical resistivity ρ, heat conductivity k and thermoelectric figure of merit ZT of Bi2S3 crystal were carried out in the temperature range between 10 K and 300 K. The Seebeck coefficient and heat conductivity measurement indicate Bi2S3 sample has thermoelectric properties, and its Seebeck coefficient is -55.520 µV/K at 300 K.
Optical properties of (Bi(Bi2S3)9I3)0.667 are characterized using transmittance and thermoreflectance measurements, which show the (Bi(Bi2S3)9I3)0.667 is an indirect semiconductor. The indirect band gap is 0.73±0.03 eV at 300 K and 0.93±0.03 eV at 30 K. The direct transition signal E1 is 1.08 eV at 300 K and 1.18 eV at 40 K by TR. Moreover, there is also a defect signal at ~0.98 eV observed at 40 K . The I-V measurements with different light sources show that the (Bi(Bi2S3)9I3)0.667 has better response in near infrared, which shows potential applications in solar energy.

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