摻雜鈰之釔鋁石榴石螢光體的放射波長約為535nm,為藍光激發之白光LED用螢光粉,由於具有良好的熱穩定性及光轉換效率,是目前製作白光LED最常用的材料。本研究係以氧化鋁、氧化釔、氧化鈰與助熔劑氟化鋁等起始原料混合,再應用固態反應法於溫度1100℃~1500℃、時間2~8小時下燒成YAG:Ce3+ 螢光粉,從實驗結果中得知在還原性氣氛下、溫度1200℃時間4小時即可合成純相YAG:Ce3+螢光粉,再將螢光粉進行螢光光譜儀檢測,得到吸收波長為340nm與470nm分別為4f(2F5/2) →5d(2B1g)以及4f(2F5/2) →5d(2A1g)之電子躍遷產生,而最強的放射峰為535nm,屬於黃綠光範圍。最後將合成之螢光粉壓製成靶材生胚,探討燒結溫度對燒結體緻密化的影響,由結果得知,採用含雜相的YAG:Ce3+ 螢光粉體,以185MPa壓力成型之生胚,於1400℃/10h的燒結可得燒結相對密度98.1%的最佳化。
Yttrium aluminum garnet phosphor doped Ce3+ ion has yellow-white emitting light , better chemical stability , excellent optical and high temperature mechanical properties which also can combine the blue light to yield white light. The YAG:Ce3+ phosphors was synthesized by solid-state reaction method. The precursor calcined at 1100℃~1500℃, 2~8 hrs then analysis by XRD and Spectrofluorophotometer. The experiment result shows the temperature and time of pure YAG:Ce3+ for calcinations is 1200℃、4hr and there are two peaks in its excited spectrum, the major one is a broad band around 470 nm, which matches the blue emission very well. The emission peak located at about 535 nm which is the typical 5d→4f transition of Ce3+ and in the wavelength rang of yellow to green light. Using the YAG:Ce3+ phosphors to shape into green and researched the sintering temperature effect on densification of target. The results show that impure YAG:Ce3+ phosphors can obtain fine relative density (98.1%) at 1400℃/10h after compacting in 185MPa.