基于Ir(piq)_3的红色磷光有机电致发光器

Red Phosphorescent Organic Light-emitting Diodes Based on Ir(piq)_3

采用真空蒸镀法制备了结构为ITO/NPB(20nm)/CBP(3nm)/CBP∶Ir(piq)3(z%,xnm)/TPBi(10nm)/Alq3(20nm)/Cs2CO3∶Ag2O(2nm,20%)/Al(100nm)的器件。研究了掺杂浓度和厚度对器件性能的影响。首先选定Ir(piq)3∶CBP层的厚度为5nm,调节掺杂浓度。结果是当掺杂浓度为10%时,器件的效率和亮度较好;驱动电压为16V时,最大亮度为8 810cd/m2。然后在10%的掺杂浓度下,调节CBP∶Ir(piq)3层的厚度。当厚度为20nm时,器件的性能较好。驱动电压为12V时,电流密度为193mA/cm2,效率为11.92cd/A;驱动电压为19V时,电流密度为302.45mA/cm2,亮度为10 990cd/m2。无论在何种浓度和厚度下,器件的色坐标都在红光范围内。

The devices were fabricated with the sturcture of ITO/NPB(20nm)/CBP∶Ir(piq)3(z%,xnm)/TPBi(10nm)/Alq3(20nm)/Cs2CO3∶Ag2O(2nm,20%)/Al(100nm)by using the method of vacuum evaporation.The performance of the devices were studied by making adjustment on the doping concentration and thickness of the red light emission layer(CBP∶Ir(piq)3).Firstly,the doping concentration was regulated when the thickness of(Ir(piq)3∶CBP)layer was fixed to be 5nm.And it is concluded that the device has the maximum luminance of8 810cd/m2 when the doping concentration is 10%.Then the thickness of(CBP∶Ir(piq)3)layer was adjusted with keeping the doping concentration as 10%.And it is conclude that when the thickness is 20 nm,the device obtains better performance.The maximum luminous efficiency is11.92cd/A and the current density is 193mA/cm2 at 12V;the maximum luminance is 10 990cd/m2 and the current density is 302.45mA/cm2 at 19 V.The CIE coordinates of the devices are all within the scope of the red region in any concentration and thickness.