用ZnS薄膜作为空穴缓冲层的高效率有机发光二极管

用磁控溅射方法制备的ZnS薄膜作为有机发光器件(OLEDs)的空穴缓冲层,使典型结构的 OLEDs(ITO/TPD/Alq/LiF/Al) 的发光性能得到改善.ZnS 缓冲层厚度对器件性能影响的实验结果表明,当ZnS缓冲层厚度为 5 nm 时,器件的亮度增加了2倍多;当ZnS缓冲层厚度为5、10 nm时,器件的发光电流效率增加40%.研究结果表明 ZnS 薄膜是一种好的缓冲层材料,它能够提高器件的发光效率,改善器件的稳定性.

Efficient Organic Light-Emitting Diodes with ZnS Thin Films as Hole Buffer Layer

An organic light-emitting diodes (OLEDs) using ZnS thin film by RF magnetron sputtering as a hole buffer layer were prepared. With the presence of the buffer layer, the devices using the typical struc-ture of ITO/TPD/Alq/LiF/Al performed a good electroluminescent properties compared with the devices without ZnS buffer layer. The investigation on the effects of the ZnS thickness showed that the device with 5 nm ZnS buffer layer double its luminance under driven voltage 20 V, and the current efficiency of the de-vices with 5 and 10 nm ZnS is improved by about a factor of forty percent compared with the devices with-out buffer layer. The results suggested that ZnS may be a good anode buffer layer material and can improve the efficiency and stability of OLEDs.