林雯嫣
【摘 要】为了有效的提高有机电致发光器件(OLED)的电子注入和传输能力,从而提高器件的亮度和效率,本文利用碱金属Cs作为n型掺杂剂,对电子传输材料Bphen进行掺杂。以热蒸镀的方式,制作了结构为ITO/HAT-CN/TAPC/Alq3/Bphen/Bphen:Cs/Al的掺杂器件,掺杂浓度为5%,同时,制作了未掺杂Cs的器件作为参考器件。实验表明,器件的开启电压仅为2.35V,在7V的驱动电压下,可以达到44700 cd/m2的最大亮度,是未掺杂器件的三倍以上,同时,电流效率达到最大值5.17cd/A,高于未掺杂器件。
【关键词】Cs;有机电致发光器件;亮度;电流效率
中图分类号: TN383.1 文献标识码: A 文章编号:2095-2457(2018)08-0065-002
Improved efficiency and luminance of organic light-emitting device by utilizing Cs doped
LIN Wen-yan
(College of Information Science and Engineering,Huaqiao University,Xiamen 361021,China)
【Abstract】In order to effectively improve the electron injection and transmission capability of organic light-emitting devices and to improve the luminance and efficiency of the organic light-emitting devices(OLED), this article uses alkali metal Cs as an n-type dopant to dope in the electron transport material Bphen.Using the method of thermal evaporation,the structure of ITO/HAT-CN/TAPC/Alq3/Bphen/Bphen:Cs/Al was fabricated with a doping concentration of 5%. At the same time, an undoped Cs device was fabricated as a reference device . Experiments show that the doping device's turn-on voltage is only 2.35V. Under the 7V driving voltage, the maximum brightness reaches 44700 cd/m2, which is more than three times that of undoped devices. At the same time, the current efficiency reaches a maximum value of 5.17cd/A. which is higher than undoped devices.
【Key words】Cs;Organic light-emitting device; Luminance; Current efficiency
0 引言
随着科学技术的发展,自从由美籍华裔教授邓青云于1979年在实验室中发现有机电致发光器件(OLED)以后,陆续有不少研究人员投入有机电致发光器件的研究。如今,有机电致发光器件由于它轻薄,工作电压低,效率高,色域宽,发光均匀柔和,绿色环保,健康护眼等特点而越来越受到来自世界各国科研工作者以及生产商家的重视,逐渐应用在显示以及照明的领域,如三星推出了含有OLED的Galaxy Note3、Galaxy Round智能手机,LG集团推出Flexible Solutions Section的柔性照明技术等,在未来,有机电致发光器件也会有更好的发展前景。
经过各国研究者长时间的研究,在结构、材料等方面上做了各种改进,形成了现在阴、阳电极中间夹着空穴传输层、发光层、电子传输层等多层有机层的“三明治”结构[1],亮度、效率得到了很大的提高。基本原理是在一定电压驱动下,电子和空穴分别从阴极和阳极注入到电子和空穴传输层,再迁移到发光层,并在发光层中相遇,形成激子,激发辐射出可见光。……