氮氧化物綠色螢光粉體Sr1-xSi2O2N2:Eu2+的主要發光波長為530nm之綠光，具有一寬廣之激發光譜300~500nm，此粉體具有好的熱穩定性(T50遠大於150℃)，可應用於藍光和紫外光發光二極體(LED)上。
因此本研究主要利用不同方法合成氮氧化物綠色螢光粉
Sr1-xSi2O2N2:Eu2+，摻雜不同濃度之銪離子(Eu2+)為發光中心，研究其發光機制與濃度淬滅效應，並以X-ray粉末繞射行相鑑定、掃描式電子顯微鏡進行粉體之形貌與大小分析，並就合成方式對發光效率之影響做一探討，此外也藉由共摻雜鈰離子(Ce3+)為增感劑來提升螢光粉體之發光效率並探討能量轉移之機制。氮氧化物螢光粉Sr1-xSi2O2N2:Eu2+在397nm波長下的外部量子效率可由13%提升至32% ， 450nm波長下的外部量子效率可由9%提升至20%，發光效率提升之原因為螢光粉體結晶性的提升，與晶粒形貌之改善，此外利用共摻雜Ce3+與Eu2+證實了確實能增加發光強度，其能量轉移之機制為多極化交互作用之偶極-偶極的能量轉移。
將本研究合成之綠色螢光粉體搭配商用紅色螢光粉與主波長450nm-LED結合製作成白光LED，並在驅動電流為300mA下，測試其元件特性，可獲發光效率為26ml/w，色溫4072K，CIE=(0.37,0.36) ，演色性為82之白光-LED。

In this study, SrSi2O2N2:Eu2+ oxynitride phosphors were successfully synthesized by different methods and the improvement of the quantum efficiency of phosphors were discussed. The photoluminience (PL) and excitation (PLE), quantum efficiency, thermal stability, x-ray diffraction, and morphology were investigated. In addition, the Ce3+ ions were co-doped in the SrSi2O2N2:Eu2+ phosphors to enhance the luminescence intensity of phosphors; the energy transfer mechanism between Ce3+ and Eu2+ was also investigated.
The experimental results show that SrSi2O2N2:Eu2+ have broad excitation band at 300 nm~500 nm. The emission peak of SrSi2O2N2: Eu2+ green phosphors at 530 nm was observed under an excitation of 450 nm. The SrSi2O2N2: Eu2+ green phosphors have excellent thermal stability because T50 is higher than 150 oC. The external quantum efficiency was enhanced from 13% to 32% under 397 nm excitation; the external quantum efficiency was enhanced from 9% to 20% under 450 nm excitation. The external quantum efficiency enhancement was ascribed to the improvement in morphology and crystallinity of phosphors.
Finally, phosphor-converted White-LED (WLED) have been fabricated by using green phosphor SrSi2O2N2: Eu2+ and commercial red phosphor (NR619) combined with a 450 nm LED chip. The WLED exhibits a luminous efficiency of 40 lm/W, a color rendering index (CRI) of 86 and a colour temperature (CCT) of 4624 K, and CIE=(0.35,0.35) driven by 350 mA at room temperature.

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