本論文主要研究具有良好的發光特性材料，III-VI 族硒硫化鎵系列半導體GaSe1-xSx (0≤x≤1)，通過適當的硒硫成分變化來控制其光學特性，並分析放射螢光光譜以及區域掃描時間解析行為。在於這項研究中，硒硫化鎵系列半導體使用化學氣相傳導法 (Chemical Vapor Transport method, CVT) 方法生成，其外觀從 GaSe 暗紅色轉變至GaS淺黃色。從 TEM 及 XRD 分析出結晶為六方晶系結構 (2H)，晶格常數隨著硫成分的增加而降低。並利用拉曼散射光譜 (Raman scattering spectra) 中分析4 K與300 K拉曼振動模式，可以觀察到隨著硫原子增加，導致鍵長變短，以至於拉曼光譜的振動頻率增加逐漸往高波數移動，溫度變低時也出現能量藍移行為。於光激發螢光(Photoluminescence, PL) 實驗中，使用為波長375 nm的雷射作為激發源，可以量測到與熱調製光(Thermoreflectance, TR) 相對應的發光位置。在溫度相依實驗中，我們可以觀察到在4 K時有自由激子 (FXA, FXB)、束縛激子 (BXA, BXB)、缺陷態 (BXDT) 與施子受子對 (DAP)。隨著溫度上升，束縛激子 (BXA,BXB) 會逐漸變小至消失，而由自由激子 (FXA, FXB) 主導逐漸藍移，溫度越低，發光強度隨之增強，並利用 Varshni 方程式分析能隙位移變化量，隨溫度上升能隙下降。其中我們將看見依據摻雜比例不同，所導致能隙位置逐漸往寬能隙位移並對應其發光波長的變化，由GaSe (1.98 eV) 所散發紅光漸變至GaSe0.5S0.5 (2.24 eV) 綠光最終轉變成GaS (2.55 eV) 藍光，有著可見光全波段特性。並且 TR 和 PL 結果的比較，我們更加確定硒硫化鎵系列 ε 相的 PL 發散和 ε-β 相的 TR 躍遷。最終將利用時間解析光學映射系統(Time-resolved photoluminescence, TRPL) 研究其發光複合時間常數，運用時間相關單光子計數系統 （Time Correlated Single Photon Counting, TCSPC） 將所得到的不同波長放射光譜結果作時間解析，得知我們GaSe1-xSx (0≤x≤1) 系列半導體在摻雜比例多寡會影響螢光光譜時間常數，並且於區域影像映射實驗中得知缺陷捕捉效應的分布，從單晶材料 GaSe均勻分布能隙 τ_1 於晶體表面，逐漸因由參雜比例不同導致 ε-β 結構相變，混相結構越明顯，我們越能從光學映射結果中觀察到缺陷捕捉效應 τ_2 的產生，也通過低溫4 K實驗中 TRPL 結果表明 GaSe 的能隙 τ_1 為11.56 ns已經快於 GaS 的25.09 ns，證實在低溫條件下缺陷捕捉加劇，隨著硫成分的增加，壽命變得更長。通過觀察目前的實驗研究結果，我們也成功將全波長可見光特性混和出白光光譜。為未來的納米級技術應用提供了更多科學信息，有利於開發 GaSe1-xSx (0≤x≤1) 可見光區域的光電元件。

Single crystals of GaSe1-xSx (0≦x≦1) series layered solids with x=0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1 were grown by vertical Bridgman and Chemical Vapor Transport (CVT) methods.The cystal color and appearance changed from GaSe dark-red to GaS light-yellow. The crystal structure of the GaSe1-xSx series layered semiconductors was characterized using X-ray diffraction analysis (XRD) and Transmission Electron Microscope (HRTEM). X-ray analysis and Raman measurement confirm that GaSe1-xSx series crystals are crystallized in ε and β mixed-phase of two-layer hexagonal (2H) structure. The Photoluminescence (PL) and Thermoreflectance (TR) spectra of GaSe1-xSx layered semiconductors show the energy blue-shift behavior as the sulfur content increases in the series alloy compounds. Experimental analysis shows that the entire solid series are direct bandgap materials. In the visible light region, the energy of photons ranges from GaSe (1.98 eV) red light gradually becomes GaSe0.5S0.5 (2.24 eV) green light and finally becomes GaS (2.55 eV) blue light. From Time-resolved photoluminescence (TRPL) experiments at 4K, as the sulfur content increases, the lifetime becomes longer and gives the time constant τ_1 band edge of 11.56 ns for GaSe, which is faster than that GaS, about 25.09 ns, respectively. This condition proves that GaS possesses more stacking faults and defects. The GaSe1-xSx series crystals have the potential to manufacture optoelectronic devices in the red to blue-visible region and also white lightening devices for display technolgy.

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