為了製作高演色性之白光LED，利用近紫外LED驅動紅綠藍三基色螢光粉為一可行的方式，因此本研究利用固態反應法合成適用近紫外激發之矽酸鹽類
Ba1-xSrxZrSi3O9:Eu2+藍色螢光粉與Ba2MgSi2O7:Eu2+綠色螢光粉。前者螢光粉隨Sr2+摻雜濃度提高放射峰由477位移至483 nm；後者放射峰為508 nm，且熱穩定性T50均大於140oC。在405 nm波段激發下，最佳化之Ba0.5Sr0.4ZrSi3O9:0.1Eu2+及Ba1.94MgSi2O7:0.06Eu2+螢光粉的外部量子效率分別為44.14%與35.64%，由於此兩種螢光粉具有寬廣的激發光譜，在300-420 nm有較強的吸收，皆適合應用在近紫外LED。
其中Ba1-xSrxZrSi3O9:Eu2+螢光粉利用Sr2+取代Ba2+，主體晶格場變強，結晶性變好，更多Eu3+被還原成Eu2+，且摻雜Sr2+會使結構的非對稱性增加，Eu2+之間的能量傳遞被阻礙，可降低其非輻射緩解機率，濃度淬滅點由6mol%提升至10 mol%，發光強度提升34%，反觀以Ca2+取代時，晶格扭曲過大，不易取代主體中Ba2+位置，合成時有雜項產生，發光強度大幅下降；最後以NH4Cl作為助熔劑，可幫助離子擴散與結晶反應之進行，加入8wt% NH4Cl可提升Ba0.5Sr0.4ZrSi3O9:0.1Eu2+藍色螢光粉外部量子效率5%。Ba1.94MgSi2O7:0.06Eu2+綠色螢光粉部分則利用過量Si的摻雜可以補足煆燒時Si的揮發，成功合成出單一結晶相之化合物。
將上述合成藍色與綠色螢光粉搭配氮化物Ca2Si5N8:Eu2+紅色螢光粉封裝在近紫外405 nm LED上，利用遠距式分層塗佈方式，紅色螢光粉在下層，藍色混和綠色螢光粉在上層塗佈結構，藉由調整螢光粉之厚度製作不同色溫之高演色性白光LED，其最佳白光LED之照明效率、C.I.E座標、色溫、演色性分別為22.21 lm/W、(0.3566, 0.3582)、4606 K、93.8。

In this study, Ba1-xSrxZrSi3O9:Eu2+ and Ba2MgSi2O7:Eu2+ silicate phosphors were synthesized, which could be well excited by near-ultraviolet (near-UV) lights by the solid-state reaction. The emission wavelength of the former red shifted from 477 to 483 nm with increase of Sr2+ content and the latter was at 508 nm, both of them exhibited good thermal stability with T50 > 140oC. The external quantum efficiency of optimized Ba0.5Sr0.4ZrSi3O9:0.1Eu2+ and Ba1.94MgSi2O7:0.06Eu2+ were 44.14% and 35.64% under 405-nm excitation, respectively.

The pc-WLEDs were fabricated by the near-UV LED chips (405 nm), Ba1.94MgSi2O7:0.06Eu2+, Ba0.5Sr0.4ZrSi3O9:0.1Eu2+ and Ca2Si5N8:Eu2+ phosphors utilizing separated-layers structure (red phosphor layer was above blue and green phosphor) and the silicone gel as the remote layers. By adjusting the thickness of the phosphors to produce white LEDs of high CRI with different color temperature. The optimum luminous efficiency, C.I.E. coordinates, correlated color temperature (CCT), and CRI were 22.21 lm/W, (0.3566, 0.3582), 4606 K, and 93.8, respectively.

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