本篇論文利用光激發螢光光譜及光調制光譜來分析鍺量子點在氮化矽/二氧化矽結構的發光特性。在不同尺寸量子點的光激發螢光光譜中，量子點的訊號能量會隨著尺寸增加而減小，符合量子尺寸效應。在變溫實驗中，量子點半高寬隨溫度增加無明顯變化，半高寬與量子點尺寸不均勻有關。由不同量測溫度下改變激發功率實驗中，得知電子電洞在量子點內的複合機制為激子複合。最後從氮化矽及矽氧化物的量測光譜中得知量子點訊號會受到氮化矽及矽氧化物的螢光訊號影響。

In this thesis, we have studied the emission characteristics of Ge QDs embedded in Si3N4/SiO2 matrices by photoluminescence (PL) and photoreflectance (PR). The size dependent PL spectra shows a redshift of the peak energy with increasing QD size. The effect is consistent with the quantum confinement effect. The temperature dependent PL spectra shows that increasing temperature makes a small change in the full-width- half-maximum (FWHM) and the FWHM is related to the non-uniform QDs size distribution. In the power dependent PL measurements under various temperatures, the recombination between electrons/holes is dominated by exciton recombination in the Ge QDs. In the spectra of Ge QDs、Si3N4、SiO2 and Si, the emission signals in Si3N4 and SiO2 films affect the PL emission of Ge QDs.

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