LiF超薄层引起的OLEDs发光光谱展宽(英文)

A Novel Spectrum Expanding Phenomenon Based on Inserting LiF Layer in Emitting Layer in OLEDs

将LiF插入到发光层Alq3中,制备了有机电致发光器件(OLED),其器件的结构为:ITO/NPB(45 nm)/Alq3(x nm)/LiF(0.3 nm)/Alq3[(45-x)nm]/Al(150 nm)。发现器件的电致发光谱(Electroluminescence spectra,EL)有非常明显的展宽现象,这为白光器件的制备提供了一条简单的途径。通过对比LiF在Alq3中不同厚度处的发光谱,发现在x=10时谱线展宽最显著,器件最大亮度在22 V时达到8 260 cd/m2,最大效率可达4.83 cd/A,并对其光谱展宽的机理及器件特性进行了分析。

A novel organic electroluminescent device was fabricated by interposing a thin LiF layer in Alq3 layer in this work. The structure of the device is ITO/NPB （45 nm）/Alq3 （x nm）/LiF （0.3 nm）/Alq3 [ （45 -x） nm]/ Al （150 nm）. All the devices （x =5, 10, 15） showed expanded EL spectra, and the spectrum expanding is more obvious in the device with x = 10 than the others. The highest brightness of this device reached 8 260 cd/m^2 at a fixed bias of 22 V. The spectra contain tricolor, so this is a simple method to realize white light emitting. We also elucidated the mechanism for expanded EL spectra and investigated the properties of these devices.