本論文藉由光激螢光光譜(PL spectra)及拉曼光譜(Raman spectra)來分析鎘濃度為0%、9%、14%、17%及20%的氧化鎘鋅樣品與鎂濃度為0%、3.8%、11.5%、13.2%的氧化鎂鋅的光學特性及聲子行為。
藉由氧化鋅摻雜不同濃度的鎂原子或鎘原子形成可以氧化鎂鋅或氧化鎘鋅，為調變能隙與發光波段的方法之一，但同時也會使樣品螢光訊號半高寬增加。由變溫光激螢光光譜可知，氧化鎘鋅與氧化鎂鋅會形成侷域態(localized state)，造成螢光訊號峰值隨溫度上升呈現異常藍移的現象。藉由Eliseev模型可以分析不同樣品中侷域能態的能量分布情形。
由拉曼光譜可知，鎂原子與鎘原子的摻雜會使氧化鎂鋅與氧化鎘鋅拉曼訊號峰值偏移、半高寬增加且呈現不對稱的情況，表示晶格振盪較為混亂，聲子受到摻雜原子侷限，造成選擇規則q=0的限制更為寬鬆。在論文中我們分別利用MREI模型與空間相關模型(Spatial correlation model) 的理論預測和實驗上拉曼訊號峰值偏移量與不對稱性進行比較。

In this work, we measured the photoluminescence spectra and Raman spectra to analyze the optical properties and phonon behaviors of Zn1-xCdxO (x = 0%, 9%, 14%, 17%, 20%) and Zn1-xMgxO (x = 0%, 3.8%, 11.5%, 13.2%).
Zinc oxide (ZnO) with different content Mg or Cd incorporation is one of methods to tune bandgap and emission wavelength, but also one of reasons to make PL signal broadening. From temperature dependent PL spectra, the localized states in Zn1-xCdxO and Zn1-xMgxO were observed and there will be an anomalous blue shift in its temperature dependent PL peak. Then, Eliseev’s model can be used to realize the dispersive energy of the localized state.
From our Raman spectra, by Cd (Mg) incorporation, LO phonon signal peak position is red-shifting (blue-shifting) and phonon signal peak shape is broadening and becoming asymmetric. This is described that the disorder of lattice vibration and there exists the confinement effect which leads to a relaxation of the q=0 selection rule. In this essay, we compare experimental value of Raman peak shift and asymmetric Raman peak shape with theoretical value calculated by MREI model and spatial correlation model.

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