OLED器件的性能测试与分析及其光谱优化

【作者】 陈伟；

【导师】 饶海波；

【作者基本信息】 电子科技大学 ， 光学工程， 2006， 硕士

【摘要】 有机电致发光器件(OLED)采用有机薄膜作发光层,能够在低驱动电压下实现有效的电致发光。自1987年C.W.TANG等人报道了低电压、高效率的有机小分子电致发光器件以来,OLEDs获得了飞速的发展,并很有希望成为下一代显示器的主导技术。在OLED研究过程中,对器件性能的表征工作起到十分重要的作用,本文利用自主开发的测试平台(包括软件、硬件的搭建),对不同材料、结构、工艺的小分子OLED器件进行了光学、电学性能的测试和评估,并依照色度学、半导体电输运等理论成功的对测试结果作出了定性分析,揭示了制约器件工作性能的相关因素,为器件性能的进一步优化奠定了基础、指明了方向。论文首先对有机电致发光(OLED)的发展历史作了一个简要的回顾,对OLED的发光机理进行了阐述;在第三章中,介绍了测试平台的软硬件建设,并在不同的驱动方法方式下对器件的稳定性进行了测试分析。有机物发光的特点是发光光谱的谱峰较宽、色纯度不高,从而直接导致OLED器件的色还原性变差。改善色纯度常用的方法就是选通滤光,本文第四章介绍了编写软件模拟滤光片的作用,对OLED色纯度进行优化的工作,以达到了改善器件的光学性能的目的,得出了一些有意义的结论。有机发光器件的载流子注入、传输、复合过程与器件本身的材料、结构、工作电压密切相关。基于不同的物理模型对OLED器件的工作原理提出了不同的解释。本文的第五章通过对OLED器件电压-电流特性曲线的测试和分析(包括稳态、瞬态工作模式),在对器件施加瞬态电压时观察到一些有趣的现象:如前向扫描加压过程中在负压段出现了正向瞬态电流;零电流电压漂移(向负压方向),并且发现电流瞬态特性与测试延迟时间密切相关。文中尝试用P型有机功能层中深受主型陷阱能级的存在,以及深能级较长的充放电时间特性对OLED器件中载流子输运过程的影响来定性解释上述现象,获得了比较满意的结果,为器件进一步的性能优化找到了方向。更多还原

【Abstract】 The basic configuration of organic light-emitting device (OLED) consists of a number of ultra-thin organic layers between two electrode. Under low applied voltage, the recombination of carriers coming from cathode and anode can produce intense light output. Since C. W. Tang et al reported the small molecule organic light-emitting device with high efficiency under low operating voltage in 1987. OLEDs have been paid much attention and be vastly recognized as a most promising technology for next generation of display.Characterization of performances plays an important role in the study of OLED. In this dissertation, by virtue of self-developed test system, the studies on the optical and electric properties of OLED of little molecule with different material, configuration manufactured with different processes have been presented. Concepts of chromatics and the mechanism of carrier transportation in the semiconductor device have been applied here to qualitatively analysis and interpret the result of measurement. Some interesting conclusions have been given which will be helpful in the further optimization of the performances of OLED.Firstly, the history and the principle of OLED is introduced in this paper.In chapter 3, the configuration and construction of the self-developed test system has been described in detail. With this system, a series of measurment test has been done to evaluate the stability of the same OLED under different drive voltage.As organic fluorescent materials have a broad emission band and poor luminance purity of the luminance color, the color reproduction of image of OLED is poor compared with that of other display devices such as CRT, LCD etc. the most popular method to improve the chromaticity of a system is the application of appropriate filter. Chapter 4 introduce the work that how to make a program to simulate the effect of a real filter. The work on the simulation of filter, which was applied to the OLED to improve the characteristic of chromatics of emission, was introduced. Some conclusions have been given here. According to the program results, A fit filter can be chosen to improve更多还原