本論文化學氣相傳導法(CVT)成長CuMP2S6 (M=In ,Cr)系列之含磷硫屬化合物晶體，此系列晶體材料能隙涵蓋甚廣，可從紫外光至紅外光，因此現今有許多研究學者對此系列材料極為有興趣並加以研究與探討，期許在此系列較新穎的材料中能有突破性的發展與應用。
本論文並對此系列晶體進行元素成分分析、晶體結構分析、光學量測其特性加以研究以及討論。藉由能量散佈光譜儀確定成長的材料之元素比與預期成分相同，確保我們成長出的晶體品質以及量測實驗分析的可信度。經由X射線晶格繞射分析儀分析CuInP2S6與CuCrP2S6之結構維持於單斜結構，並藉由布拉格公式及單斜結構公式計算出兩種材料的晶格常數，CuInP2S6的晶格常數a=6.081Å、b=10.557Å、c=13.600Å、β=107.101°，CuCrP2S6的晶格常數a=6 .000Å、b=10.234 Å、c= 13.402 Å、β=106.705°。以固態雷射633nm紅光與532nm綠光雷射為激發源量測拉曼散射光譜可觀察到P-S、P-P、S-P-S與S-P-P四種內部震動模態。隨著溫度的下降，使用雷射633nm紅光，拉曼峰值往高波數位移，尤其是CuCrP2S6晶體在低溫下的拉曼譜線，除了內部震動模態強度增加，且可以觀察到室溫下所沒有的新震動模態。
　　光學量測實驗中，藉由光穿透實驗與調制光譜實驗，可得知兩種材料的激子躍遷訊號位置其能隙。CuInP2S6的室溫躍遷訊號在 2.7 eV，當溫度下降至約100K，可觀察到第二激子的出現，並計算出第一激子之游離能40 meV，且在低溫30K時直接能隙Eg=3.007eV；CuCrP2S6的室溫躍遷訊號在1.26 eV，在低溫30K時移至1.34 eV。
在光穿透實驗中，CuCrP2S6 的吸收光範圍落在紅外線區，而CuInP2S6 的吸收光範圍落在可見光區。最後在熱探針實驗中，我們可以得知CuInP2S6與CuCrP2S6皆為P-type半導體。
　　綜合以上幾點可得知，CuInP2S6與CuCrP2S6晶體雖有相同的晶體結構，激子躍遷位置、光吸收範圍及拉曼光譜卻大為不同，本研究提出此兩種材料之基礎與光學研究，得以提供未來科技之應用上有突破性的發展。

The layered crystals of CuMP2S6 (M=In, Cr) phosphorus-containing complex chalcogenides series were grown by chemical vapor transport (CVT) method, using I2 as a transport agent. This series of crystal materials include a wide range of energy gap, from ultraviolet light to infrared light. Therefore, many researchers are very interested in this series of materials and research and discuss it. Detailed characterization of the materials were carried out by using Energy-dispersive X-ray spectroscopy (EDS), X-ray Diffraction (XRD), Raman spectroscopy, Thermoreflectance (TR), Piezo-modulation reflectance (PzR), Transmittance (Tr), and Hot probe experiments.
　　X-ray analysis confirmed that CuInP2S6 and CuCrP2S6 are crystallized in monoclinic structure, Using Bragg's Law and monoclinic formula to calculate the lattice constant, lattice constant of CuInP2S6 are a=6.081Å, b=10.557 Å, c=13.600 Å,β=107.101°, for CuCrP2S6 are a=6.000 Å, b=10.234 Å, c=13.402 Å, β=106.705°. For Raman experiment, we can observe a lot of internal vibrations that may be divided into four groups, which will be referred to be the P-S, P-P, S-P-S, and S-P-P modes. As the temperature decreases, the Raman peak shift to high wavenumber, and the Raman intensity of the CuInP2S6 and CuCrP2S6 at low temperature increases.
　　Optical properties of CuInP2S6 and CuCrP2S6 were characterized using thermoreflectance (TR), piezo-modulation reflectance (PzR), transmittance measurement (Tr), which showed that CuInP2S6 and CuCrP2S6 are direct semiconductor. The band gaps of CuInP2S6 and CuCrP2S6 are 2.7 eV and 1.26 eV at 300 K, and the light absorption range are in the visible to infrared region. For CuInP2S6, in modulation spectroscopy experiment, as the temperature decreases, the binding energy of the first exciton can be calculated to be 40 meV, and the direct energy gap Eg=3.007eV at 30K. From hot probe measurement, CuInP2S6 and CuCrP2S6 are classified as P-type materials.
　Based on above experimental results, CuInP2S6 and CuCrP2S6 crystals have the same crystal structure, but their energy gap, absorption range and Raman spectrum are quite different. This work provides fundamental basis and optical studies of these two materials for development and application of future technology.

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