本論文利用化學氣相傳導法，成長出過渡金屬硫屬化合物半導體材料 CuInP2Se6，並研究其結構、光學與電學特性。藉由能量色散X射線光譜、X 射線光電子能譜儀確認成長之材料成分與預期相符。高解像能電子顯微鏡與X射線晶格繞射分析儀確認 CuInP2Se6 為六方晶系。從極化拉曼及溫度相依拉曼實驗中，觀察到不同極化角度下之各振動模態的消長變化。光學量測中，利用顯微光激螢光光譜、光穿透及熱調制反射光譜實驗，確認材料能隙位置。CuInP2Se6 300 K 時，直接能隙約為 1.6 eV，隨溫度降低而藍移約至 1.83 eV。120 K 時觀察到 1.311 eV 的缺陷束縛激子訊號；溫度相依拉曼實驗120 K 時，結果顯示在溫度 120 K 時會出現新的振動模態，表明 CuInP2Se6 在此溫度下時可能發生結構相變或電荷重排等現象。電學量測中，利用熱探針及霍爾量測實驗確定 CuInP2Se6 為 p 型半導體，室溫時電阻率為2.57×104 Ω-cm，載子濃度 5.09×1011 cm-3。從溫度相依電阻率實驗中，其電阻率隨溫度降低而增加，呈現半導體行為。在照光之 V-I 量測中，表明 CuInP2Se6 具有明顯的光吸收效應及光電效應。上述結果顯示 CuInP2Se6 在光學和電子元件中具有應用潛力，如光催化、相變化記憶體和光電子元件等。

In this work CuInP2Se6 single crystals are grown using the ChemicalVapor Transport (CVT) method with Iodine (I2) as the transport agent. Thestructure, optical, and electrical properties of CuInP2Se6 are investigated. TheEnergy-dispersive X-ray Spectroscopy (EDS) and X-ray PhotoelectronSpectroscopy (XPS) measurements are employed to validate that the grownmaterial has the expected composition. Furthermore, High-ResolutionTransmission Electron Microscopy (HRTEM) and X-Ray Diffraction (XRD)analyses reveal that CuInP2Se6 belongs to the hexagonal crystal system. Theangular-dependent micro-Raman spectroscopy is conducted within thetemperature range of 8 K to 300 K. The results reveal variations in thevibrational modes at different polarized angles with a new peaks is observed asthetemperature decreases to 120 K. Optical measurements, includingMicroPhotoluminescence (μPL), Transmittance, and Thermoreflectance (TR) arecarried out to determine the bandgap positions of the crystals. CuInP2Se6 has adirect bandgap of approximately 1.6 eV at 300 K, which blue shifts toapproximately 1.75 eV with decreasing temperature to 20 K. At 120 K, a defectboundexciton signal is briefly observed at 1.311 eV. The temperaturedependent Raman spectroscopy also reveals novel Raman peaks at 120 K,indicating that CuInP2Se6 at this temperature may undergo structural phasetransitions, lattice distortions, or charge rearrangement phenomena. Electricalmeasurements using a hot probe and the Hall Effect confirm that CuInP2Se6 isa p-type semiconductor with a resistivity of 2.57 × 104 Ω-cm and a carrierconcentration of 5.09 × 1011 cm-3. The temperature-dependent resistivityexperiment demonstrates an increase in resistivity as the temperature decreases,indicating semiconductor behavior in CuInP2Se6. The photo V-I measurementsof CuInP2Se6 show a significant photo response, indicating its strong lightabsorption and high capacity for generating photocurrent, thereby making it aphotosensitive material. In summary, CuInP2Se6 exhibits promising characteristics that make it a promising candidate for integration intooptoelectronic devices, photocatalysis systems, phase-change memory andphotonic devices.

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