倒置型PLED的电致发光特性研究

Study on Electroluminescence of Inverted PLED

提出一种以聚合物MEH PPV为发光材料,结构为Al/MEH PPV/CuPC/ITO的倒置型发光器件(I PLED)。对既是空穴传输层又是轰击缓冲层的CuPC厚度以及MEH PPV的浓度对器件性能影响的分析发现,在实验条件下,最佳的CuPC厚度约为3.5nm,最佳的MEH PPV浓度约为3‰;采用小分子染料红莫稀(Rubrene)对聚合物发光材料MEH PPV掺杂发现,器件的亮度从未掺杂的40 4cd·m2提高到掺杂后的207.7cd/m2,其发光峰从未掺杂的624nm蓝移到掺杂后的592nm,但其I V特性并没有明显的变化。

A novel Al/MEH-PPV/CuPC/ITO inverted organic light emitting diode (lPLED) structure was proposed, in which MEH-PPV acts as luminescence layer and CuPC acts as the hole transport layer as well as the buffer layer for ITO sputtering. The influences of the thickness of CuPC and the concentration of MEH-PPV on the device characteristics were investigated. It is found the suitable thickness of CuPC is around 3.5 nm and the suitable concentration of MEH-PPV is around 3‰.The luminescence of this IPLED was improved from 40.4 cd&middotm2 to more than 207.7 cd/m2 by doping Rubrene in MEH-PPV compared with the IPLED with undoped MEH-PPV, its peak of the electroluminescence spectrum moves from 624 nm to 592 nm, while its I-V curve does not show a remarkable change.