摘要
模拟无机大功率白光LED由蓝光芯片激发荧光粉形成白光的发光方式,基于有机电致蓝光器件激发黄色的YAG∶Ce荧光粉来实现全色器件。采用真空蒸镀法,制备了ITO/2T-NATA(30 nm)/AND∶TB-Pe(50 Wt%,40 nm)/Alq3(100 nm)/LiF(1 nm)/Al(100 nm)的蓝光器件,然后在出光面用点胶机均匀涂覆一层不同厚度的黄色的YAG∶Ce荧光粉制备出了不同色坐标的全色器件。用蓝光器件激发黄色YAG∶Ce荧光粉可以减少有机电致发光全色器件的制备工艺和难度,并且可以利用已经非常成熟的荧光粉技术。通过实验发现,涂覆荧光粉得到了光谱稳定的白光器件,涂覆荧光粉层器件的最高亮度为13 840 cd.m-2,相比蓝色器件可以提高接近2倍,涂覆荧光粉器件的发光效率最高可达到17.3 cd.A-1,相比蓝色器件的最高光度效率提高了2倍多。对涂覆荧光粉层器件的光谱特性进行了讨论,荧光粉的浓度和厚度会影响器件的光谱特性,并存在最佳工艺参数,在荧光粉层浓度和厚度既定的情况下,器件的绝对光谱值与驱动电流成正比例。
It is demonstrated that the panchromatic luminescence devices with organic blue-ernissive light-emitting was fabrica- ted. This technique used down conversion, which was already popular in inorganic power LEDs to obtain white light emission. A blue OLED device with a configuration of ITO/2T-NATA（30 nm）/AND ： TBPe（50 Wt%, 40 nm）/Alq3 （100 nm）/LiF（1 nm）/ Al（ 160 nm） was prepared via vacuum deposition process, and then coated with YAG ： Ce phosphor layers of different thicknes- ses to obtain a controllable and uniform shape while the CIE coordinates were fine tuned. This development not only decreased steps of technics and degree of difficulty, but also applied the mature technology of phosphor. The results showed that steady spectrogram was obtained in the devices with phosphor, with a best performance of a maximum luminance of 13 840 cd · m-2 which was about 2 times of that of the devices without phosphor; a maximum current efficiency of 17.3 cd · A-1 was increased more two times more than the devices without phosphor. The emission spectrum could be adjusted by varying the concentration and thickness of the phosphor layers. Absoulte spectrogram of devices was in direct proportion with different driving current corresponding.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2011年第9期2337-2340,共4页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(50372038)
浙江省温州市科技局项目(H20080004)
陕西科技大学科研启动基金项目(BJ09-07)
陕西科技大学研究生创新基金项目资助
