新型螢光粉之製備、理論計算與發光特性鑑定用於白光發光二極體之研究

Synthesis, Theoretical Calculations and Luminescent Properties of Oxide-Based Phosphors for White Light-Emitting Diodes Applications

張之辰(Jy-Chern Chang)

指導教授 ： 劉偉仁

中原大學/工學院/化學工程研究所/碩士(2018年)

https://doi.org/10.6840/cycu201800368

摘要

近年來發光二極體由於其擁有多項優點而被廣泛應用於顯示器及照明系統上。市面上常用藍光晶片搭配黃光螢光粉作為白光發光二極體，此類型的白光發光二極體其演色指數偏低。因此為獲取高演色指數的白光發光二極體，可使用紫外光晶片搭配RGB三色螢光粉透過混光製備白光發光二極體。本研究將致力於探討新穎紫外光激發螢光材料之合成與發光特性之分析與應用。
本研究主要將主體結構透過摻雜銪二價離子和釤三價離子等兩種不同的稀土離子，藉由高溫固態反應法合成並探討其發光特性及應用於白光發光二極體之封裝。本研究共探討四支新穎螢光粉，如:SrCa2MgSi2O8:Eu2+、 Sr8CaZn1.5(PO4)7:Eu2+、BaLa4Ti4O15:Sm3+和KBaYSi2O7:Sm3+，在發光特性分析上主要有X光繞射分析、晶體結構分析、光致發光光譜、量子效率計算、漫反射光譜、變溫光譜、電致發光光譜、時間解析光譜、演色指數、CIE色度座標和LED封裝。

關鍵字

螢光粉、光致發光、發光二極體

並列摘要

In recent year, white light-emitting diodes (w-LEDs) have caught much attention for the application of display and illuminating systems owing to their great advantages. The commercial white light-emitting diodes is to fabricate the blue InGaN chips with yellow-emitting phosphors such as YAG:Ce3+ phosphors. However, it has unavoidable problems, such as low color rendering index and high correlated color temperature. Therefore, it is necessary to develop other approaches to obtain w-LEDs generated by means of near-ultraviolet (NUV) chips. In this way, w-LEDs are produce by mixing blue, green and red-emitting phosphors with NUV chips. Finally, we can acquire high CRI w-LEDs. In this study, we mainly focus on the synthesis and investigation of the phosphors for applications of white light emitting diodes (w-LEDs).
We discussed on two kinds of rare earth ions-doped (Eu2+ and Sm3+) phosphor which were successfully synthesized the phosphors by the high temperature solid state reaction. To further discussions, we used a series of analysis such as X-ray diffraction (XRD), photoluminescence spectra (PL), temperature-dependence photoluminescence spectra (TL), decay lifetime, diffuse reflection spectra, LED fabrication, CIE coordinate and so on to identify the structural and luminescent properties of SrCa2MgSi2O8:Eu2+, Sr8CaZn1.5(PO4)7:Eu2+, BaLa4Ti4O15:Sm3+ and KBaYSi2O7:Sm3+ phosphors. All the phosphors were fabricated with NUV chips and compared with commercial w-LEDs fabricated with yellow-emitting phosphors and blue chips. The study indicated that SrCa2MgSi2O8:Eu2+, Sr8CaZn1.5(PO4)7:Eu2+, BaLa4Ti4O15:Sm3+ and KBaYSi2O7:Sm3+ are the most potential phosphors for NUV chips-pump w-LEDs.

並列關鍵字

Phosphor, Photoluminescence, Light-emitting diodes

參考文獻

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