基于双蓝光有源区激发YAG:Ce荧光粉的高显色性白光LED  

Highly color rendering YAG:Ce phosphor-converted white light-emitting diode based on dual-blue emitting active regions

作　　者：石培培[1] 严启荣[1] 李述体[1] 章勇[1] 

机构地区：[1]华南师范大学光电子材料与技术研究所,广州510631

出　　处：《功能材料与器件学报》2012年第3期255-261,共7页Journal of Functional Materials and Devices

基　　金：国家自然科学基金项目(No.U1174001);教育部留学回国人员科研启动基金项目;广东省自然科学基金项目(No.S20110100034000)

摘　　要：在(0001)蓝宝石衬底上利用金属有机化学气相沉积系统,分别生长含有p-AlGaN电子阻挡层和反对称n-AlGaN层的双蓝光波长发射的InGaN/GaN混合多量子阱发光二极管(LED)。结果发现,与传统的具有p-AlGaN电子阻挡层的双蓝光波长LED相比,这种n-AlGaN层能有效改善电子和空穴在混合多量子阱活性层中的分布均匀性和减少电子溢出,并减弱双蓝光发射光谱对电流的依赖性。此外,基于这种双蓝光波长发射的芯片与YAG:Ce荧光粉封装成白光LED能实现高显色性的白光发射,在20 mA电流驱动下,6500 K色温时显色指数达到91,而基于单蓝光芯片的白光LED显色指数只有75。Dual- blue wavelength light -emitting diode （LED） based on mixed InGaN/GaN quantum wells was grown sequentially on the （0001） sapphire substrate by metal -organic chemical vapor deposi- tion （MOCVD） with p -A1GaN and asymmetry n -A1GaN, respectively. It was found that the asymmetry n - A1GaN layer can improve the distribution uniform of electrons and holes and deduce electron overflow relative to the conventional p - A1GaN, and further reduce the dependence of dual - blue wavelength e- mission spectrum on driving current. In addition, highly color rendering white light emission has been re- alized from YAG：Ce phosphor - converted white LED based on dual - blue wavelength chip, the color rendering index （CRI） of the corresponding white LED reached 91 at a forward current of 20 mA while that of white LED based on single - blue wavelength chip was only 75.

关 键 词：n-AlGaN p-AlGaN 混合量子阱 双蓝光波长 显色指数 

分 类 号：TN312.8[电子电信—物理电子学]