不同功能层对有机电致发光器件的发光特性影响的研究

发布时间：2018-03-17 11:32

本文选题：有机电致发光器件　切入点：蓝光OLED　出处：《哈尔滨工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：有机电致发光器件(Organic Light-Emitting Diode,OLED),是以有机物为发光材料的新型电致发光器件。凭借着其制备工艺简单、视角宽、响应时间短、发光亮度高、全固体化、重量轻、可实现柔性化器件、全色显示等一系列独特的优点,OLED有望成为新一代显示和照明的的中坚力量,在显示器件中极具竞争力,被认为是未来的主流平板显示技术,引起了人们的广泛关注。经过几十年的发展,有机电致发光器件开始走向成熟。但是有机电致发光器件在结构优化、器件效率等方面还不尽人意。因此,各国研究人员都努力着去优化器件的性能。本文通过对不同结构OLED器件的发光机理、制备工艺以及电学特性、载流子迁移率的计算和光学特性的分析,主要研究了有机电致发光器件中不同功能层对器件性能的影响,不同有机电致发光材料性能以及有机电致发光器件的结构与发光理论模型。由于有机电致发光器件的每个功能层厚度都在纳米量级,最薄的空穴隔离层可以达到1 nm的厚度,所以在实验制备过程中,尽量减少污染,控制成膜特性都成为制备高质量器件的关键因素。实验采用真空热蒸镀进行有机物的镀膜、采用电阻热蒸镀进行无机物和金属电极的蒸镀,完成发光器件的制备。采用Alq3和CBP作为发光物质,从最基本的单层器件(只包含阴极、发光层和阳极)开始,逐渐加入空穴传输层(有机材料NPB)、空穴隔离层(无机材料LiF)和空穴注入缓冲层(无机材料三氧化钼),分别测量每一种器件的电流—电压关系、进而计算得到电流密度—电压的关系。利用空间电荷限制电流法(SCLC)和构造特殊函数法,计算器件内载流子的迁移率,并与文献中的载流子迁移率的大小进行对比,判断器件质量。进一步测量器件发光光谱,发光亮度—电压关系,确定器件的开启电压、最佳工作电压和击穿电压等。而在对OLED的研究中,制备蓝光器件是OLED发展的重中之重,无论是对显示还是白光OLED照明的研制都具有非常重要的意义。尤其是非掺杂蓝光OLED器件在之前的实验中并没有被广泛报道过。而本文成功制备的结构为Glass/ITO/MoO3/NPB/CBP/LiF/Al的蓝光OLED在之前并没有被深入研究,其发光光谱峰值位于450 nm和490nm,这种非掺杂的蓝光OLED结构可以为今后对蓝光OLED的研究提供参考。最后,本文从实验得到的数据中总结有机电致发光器件的发光规律。为后续研究者提供了理论上的支持。
[Abstract]:Organic Light-Emitting diode device is a new type of electroluminescent device with organic material as luminescent material. With its simple preparation process, wide angle of view, short response time, high luminescence brightness, full solids and light weight, flexible devices can be realized. A series of unique advantages, such as panchromatic display, are expected to become the backbone of the new generation of display and lighting. They are highly competitive in display devices and are considered to be the mainstream flat-panel display technology in the future. After decades of development, organic electroluminescent devices begin to mature, but there are electroluminescent devices in the structure optimization, device efficiency and other aspects are not satisfactory. Researchers all over the world are trying to optimize the performance of OLED devices. In this paper, we analyze the luminescence mechanism, fabrication process, electrical properties, carrier mobility and optical properties of OLED devices with different structures. The effects of different functional layers on the performance of organic electroluminescent devices are studied. Different properties of organic electroluminescent materials, structure and theoretical model of organic electroluminescent devices. Because the thickness of each functional layer of electroluminescent devices is in nanometer order of magnitude, the thinnest hole isolation layer can reach the thickness of 1 nm. Therefore, in the process of experimental preparation, reducing pollution and controlling the characteristics of film formation are the key factors in the preparation of high quality devices. Alq3 and CBP are used as luminescent materials, starting with the most basic monolayer devices (only cathode, luminescent layer and anode). Gradually adding hole transport layer (organic material NPBN, hole isolation layer (inorganic material LiF) and hole injection buffer layer (inorganic material molybdenum trioxide), measuring the current-voltage relationship of each device, respectively. Then the relationship between current density and voltage is obtained. By using space charge limiting current method (SCLC) and constructing special function method, the mobility of carriers in calculators is compared with the magnitude of carrier mobility in literature. Judging the quality of the device, further measuring the luminescence spectrum of the device, the relationship between luminescence brightness and voltage, determining the starting voltage, the optimum working voltage and the breakdown voltage of the device, etc. In the research of OLED, the preparation of blue light device is the most important development of OLED. Both display and white OLED lighting are of great significance, especially the undoped blue-ray OLED devices have not been widely reported in previous experiments. However, the blue light with Glass/ITO/MoO3/NPB/CBP/LiF/Al structure successfully fabricated in this paper has not been widely reported in previous experiments. OLED has not been studied in depth before, The peak luminescence spectra are at 450nm and 490nm. This non-doped blue-light OLED structure can be used as a reference for the future study of blue-ray OLED. In this paper, the luminescence law of organic electroluminescent devices is summarized from the experimental data, which provides theoretical support for the follow-up researchers.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN383.1

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