本論文是以光激螢光光譜 (PL)，針對由15K至300K的溫度變化範圍中所得之結果來探討烏采結構 (Wurtzite) 的硒化鋅鈹鎘(Cd1-x-yBexZnySe) 四元化合物晶體之光學特性,並以拉曼光譜探討其於室溫之光學特性。
文中所探討之樣品均是利用高壓布里奇曼法 (high pressure Bridgman method) 成長而成，其鈹 (Be) 與鋅 (Zn) 之濃度範圍分別為3%~15% 及3%~45%。論文中，利用勞倫茲線型 (Lorentzian lineshape)針對能帶邊際激子之PL譜線做吻合。由光激螢光光譜 (PL) 於低溫 (15K)下之譜線中可觀察到三個躍遷訊號，由高能量處往低能量處依次為能帶邊際激子譜線 (band-edge exciton line, X) 躍遷訊號、施體-受體對(donor-acceptor pairs, DAP) 躍遷訊號及深層能階 (deep level, DL) 躍遷訊號。Varshni方程式吻合分析而得的參數 會隨著鈹 (Be) 與鋅 (Zn) 的含量增加而增加。此外，由展寬參數中可觀察出，本論文討論之樣品其LO和ZnSe與一些III-V族半導體比較。本論文中分析所得之結果將與成長在磷化銦 (InP) 基板上之硒化鋅鈹鎘 (Cd1-x-yBexZnySe) 薄膜作比較並加以討論之。
此外於室溫下所量測硒化鋅鈹鎘 (Cd1-x-yBexZnySe) 之拉曼光譜中，我們可以探討其區域光聲子模態之多模態行為可發現其光聲子模態表現出三模態 (three-mode behavior) 之行為。其中BeSe-like之光聲子模態在較高頻率區域，而ZnSe-like與CdSe-like之光聲子模態則在較低頻率區域，頻率由高至低排列順序分別為BeSe-like、ZnSe-like與CdSe-like之光聲子模態，且當x～0時，BeSe-like的光學聲子模態收斂成一個頻率，像是一個Be的雜質模態 (impurity mode) 在CdSe中。

This thesis deals with the investigation of temperature dependence of the near band-edge transitions of a series of wurtzite type Cd1-x-yBexZnySe mixed crystals using photoluminescence (PL) in the temperature range 15K to 300K. This series of mixed crystals have also been studied by Raman scattering at room temperature. The crystals were grown by the modified high pressure Bridgman method from the melt with 0.03<x<0.15 and 0.03<y<0.45.
Typical PL spectrum at low temperature consists of an exciton line, an edge emission feature due to recombination of donor-acceptor pairs, and a broad band related to recombination through deep level defects. The peak positions of the exciton emission lines in the PL spectra correspond quite well to the transition energy of exciton A from previous reported electromodulation data. The parameters that describe the temperature dependence of the band edge exciton have been evaluated and discussed. The results are compared with that of the zinc-blende Cd1-x-yBexZnySe films grown on InP (100) substrates.
In addition, we can see that the optical phonons of the Cd1-x-yBexZnySe exhibit three-mode behavior at room temperature Raman spectrum. For a given x (0.03<x<0.15) and y (0.03<y<0.45) there are three pairs of optical phonons corresponding to the BeSe-like phonons in the higher frequency range and to the ZnSe-like and CdSe-like phonons in the lower frequency range. As x tends to 0 the BeSe-like optical phonons merge toward one frequency which can be regarded as the impurity mode of Be in pure CdSe.

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