本論文的研究重點在於利用化學氣相傳導法 (Chemical Vapor Transport, CVT) 成長金屬鉍化硒代磷酸鹽之化合物 AgBiP2Se6和CuBiP2Se6，並探討其材料結構、光學和電學特性。接著透過能量散射光譜儀 (Energy-dispersive X-ray Spectroscopy, EDS)、X射線光電子能譜儀 (X-ray Photoelectron Spectroscopy, XPS)、穿透式電子顯微鏡 (Transmission Electron Microscope, TEM) 結果，確認此次成長的材料與預期相符。在材料結構鑑定中，藉由X射線晶體繞射儀 (X-ray Diffraction Analysis, XRD) 分析，得到AgBiP2Se6 之晶格常數 a＝b = 6.89 Å、c＝39.39 Å；CuBiP2Se6 之晶格常數 a＝b = 6.59 Å、c＝39.78 Å，因此可得知此兩種材料皆屬於菱方晶系 (Rhombohedral)。由常溫拉曼光譜 (Raman Spectroscopy) 觀察到 AgBiP2Se6及CuBiP2Se6皆具有陽離子振盪、Se-P-Se 振動模態和 P-P 拉伸三種振動模態。其中AgBiP2Se6由於Ag離子較重，因此在陽離子震盪有較低的波數。通過極化拉曼和溫度相依實驗觀察到不同角度和溫度下各振動模態的變化。在光學量測方面，利用穿透實驗 (Transmittance) 和熱調制光譜 (Thermoreflectance, TR) 實驗得到材料的能隙位置。AgBiP2Se6 能隙為 1.47 eV，在結合溫度相依變化觀察到能量隨溫度降低而增加，逐漸藍移至 1.62 eV ，其中在100K以下，可以發現有三個峰包，推測為結構產生改變所導致，CuBiP2Se6 能隙為 1.22 eV，結合溫度相依變化觀察到能量也隨溫度降低而增加，逐漸藍移至 1.34 eV。在電學量測方面，利用熱探針實驗可得知AgBiP2Se6 與CuBiP2Se6兩種材料皆為 n 型半導體。在照光V-I量測中發現，AgBiP2Se6具有光響應，其中鎢絲燈的光響應較大，而CuBiP2Se6則無明顯光響應，推測是其濃度較高 (1017 cm-1) 所致。

AgBiP2Se6 and CuBiP2Se6 compounds were successfully grown using the chemical vapor transport (CVT) method with ICl3 as a transport agent. The material structures, optical, and electrical properties were carried out. The synthesized materials were confirmed to match the expected composition through energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) analysis. Furthermore, X-ray diffraction (XRD) analysis revealed that AgBiP2Se6 had lattice constants of a=b=6.89 Å and c=39.39 Å, while CuBiP2Se6 had lattice constants of a=b=6.59 Å and c=39.78 Å, indicating that both materials belong to the rhombohedral crystal system. Raman spectroscopy showed that AgBiP2Se6 and CuBiP2Se6 exhibited three vibrational modes: cation oscillation, Se-P-Se mode, and P-P stretching. The variations of these vibrational modes were observed through polarized Raman and temperature-dependent experiments at different angles and temperatures. The band gaps of the materials were determined through transmission experiments and thermal modulation spectroscopy. The band gap of AgBiP2Se6 was determined to be 1.47 eV at 300K and increased with decreasing temperature, shifting progressively toward higher energy to 1.62 eV at 20K. The band gap of CuBiP2Se6 was 1.22 eV at 300K and shifted towards 1.35 eV at 20K. AgBiP2Se6 and CuBiP2Se6 were confirmed to be n-type semiconductors by hot probes and Hall effect measurements. During current-voltage (V-I) measurements, AgBiP2Se6 exhibited photoresponse, with tungsten halogen lamp illumination resulting in a more significant response than CuBiP2Se6. In current-voltage (V-I) measurements, AgBiP2Se6 exhibited photoresponse, with tungsten halogen lamp illumination yielding a better response than CuBiP2Se6. Overall, the effective synthesis and exhaustive characterization of AgBiP2Se6 and CuBiP2Se6 compounds have contributed significantly to our understanding of their structural and optical properties. These results have implications for the design of optoelectronic devices using these materials.

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