摘要
采用DCJTB作为红色染料,以绿色发光材料Alq,Gaq,Inq作主体材料,分别制备了结构为ITO/TPD/Mq(M=Al3+,Ga3+,In3+)∶DCJTB/Alq/LiF的一系列红色OLED器件,目的在于研究主体与客体发光分子间的能级匹配情况对载流子的注入、限制、激子的复合及发光色纯度方面的影响。同时研究了DCJTB的掺杂浓度,发光层中发光基质与掺杂染料之间的能带匹配,以及器件的各有机层之间的能带匹配对器件发光性能的影响。分析表明,在ITO/TPD/Alq(Gaq,Inq)∶DCJTB/Alq/LiF/Al器件中,发光层中存在着从Mq向DCJTB的能量传递,Alq,Gaq,Inq与DCJTB之间的能带匹配显著地影响着这些器件的发光性能,如最大发光亮度、发光效率、色度 电压的关系等。
This thesis focus on the red organic electroluminescent materials and devices.Some different red organic thin film electroluminescent devices were prepared by vacuum evaporation.These devices have the same structures:ITO/TPD/lightemitting layer/Alq/LiF/Al,but the lightemitting layer is di fferent:that is Mq(M=Al3+,Ga3+,In3+)doped with the red dye DCJTB.The results of the emission and excitation spectra of Mq and DCJTB indicated that there exits effective energy transfer from Mq to DCJTB in the lightemitting layer.The impact of dopant concentration on EL spectrum, BJV characteristics and EL efficiency were analyzed.It is found that the color of EL device can be adjusted by dopant concentration. Meanwhile the energy level structures of these organic thin film electroluminescent devices were compared, the results show that their properties (the luminance,chromaticity,EL efficiency)can be affected by matching energy band of materials. A phenomenon was observed that the chromatic degree of light emission moves to green region gradually when the applied voltage is increased and the change of Alq device is biggest,a qualitative analyses was made to discover the reasons.
出处
《液晶与显示》
CAS
CSCD
2003年第4期271-275,共5页
Chinese Journal of Liquid Crystals and Displays
基金
国家自然科学基金(60077020)资助项目
上海市科委资助项目(97JC14001)
