柔性有机薄膜电致发光显示材料及器件

有机薄膜电致发光显示器件(OLED)近年来得到了迅猛发展,是未来全固体平板式彩色显示器的重要候选者,其最大优势之一是可以制作成柔性显示器件。本文综述了柔性有机电致发光材料及器件的发展概况、工作原理与优缺点,目前制作此类器件中存在的困难及解决这些困难的有效措施。     

柔性显示的研究进展

综述了液晶、有机电致发光及电泳显示技术的柔性显示机理及研究前沿.其中,反射式双稳态胆甾液晶和PDLC柔性显示适用于辊对辊(Roll-to-roll)连续工艺流程,但还存在响应速度较慢、驱动电压较高、对比度偏低等尚待研究解决的问题.通过聚合物墙和聚合物网络克服铁电液晶分子成近晶型排列织构易受外界压力或振动破坏的缺点,可实现铁电液晶柔性显示的高质量动画效果.具有自发光、宽视角、抗弯曲能力强等优异性能的OLED是实现柔性显示的较理想的选择.但柔性树脂基板对水、氧阻隔能力差是其实现柔性显示的瓶颈之一.EPD技术具有双稳态特点,且没有画面闪烁问题,在对响应时间要求不高的电子书、电子报等柔性显示方面具有较大的优势.     

高分子电致发光材料及器件的研究进展

高分子电致发光材料由于其卓越的性能,近年来取得了飞速发展。本文阐述了有机高分子电致发光材料的工作原理、种类及器件发展现状,并对今后的发展趋势和应用前景进行了展望。     

聚合物电致发光材料及器件

聚合物电致发光器件由于其卓越的性能,在近年来取得了飞速发展,成为科研领域的又一热点。阐述了聚合物ＥＬＤ的工作原理,器件结构、聚合物材料的种类及分子结构,综述了影响器件发光效率和寿命的因素和解决办法,介绍了聚合物电致发光材料及器件的发展现状和目前存在的问题,并对其今后的发展趋势和应用前景进行了展望。     

柔性透明导电膜衬底材料的研究进展

综述了柔性透明导电膜材料的应用以及可用作柔性透明导电膜衬底材料的种类、存在的问题和可行的解决方法。介绍了柔性透明导电膜材料的优点、应用和国内外研究现状。重点介绍了可用作柔性透明导电膜衬底的聚合物材料—聚酰亚胺和聚酯,分析了各自的特点。通过分析柔性衬底存在的不足,寻求可行的解决方法,使柔性衬底可以更好地满足导电膜对衬底材料的要求,为柔性衬底材料的设计提供依据。     

白色有机发光材料与器件

综述了白色有机电致发光材料和器件的研究进展;归纳了获取白色有机电致发光的途径和方法;分析了多种器件结构的特点及其材料;结合研究过程中存在的某些问题,从器件的发光效率和色纯度角度,讨论了影响发光器件性能的诸因素及其改进措施.     

基于静电键合的聚醚型聚氨酯基固体电解质柔性封装材料

随着小型功能化移动电子装置的高速发展,制备一种柔性、长寿命的高稳定器件替代传统的刚性电子器件的重要性愈加凸显。静电键合是一种先进的材料连接技术,其连接强度高、密封性好、键合温度低、可以实现异种材料连接等特点在柔性器件的封装中展现出巨大的潜能。传统的聚合物固体电解质室温离子电导率低、机械性能差,无法很好的用于静电键合工艺,同时也制约了静电键合在柔性器件制备与封装中的应用。聚氨酯独特的微相分离结构赋予了其良好的物理化学性能,多样化的载流子通道、可调节的柔性链段以及拥有大量可解离锂盐的极性基团等特点使其成为理想固体电解质基体材料成为可能。从4个方面综述了聚氨酯基体材料进行分子结构设计和制备工艺优化的方法,旨在提高其室温离子电导率和机械性能,适合于静电技术的柔性器件封装。     

有机发光器件的研究进展

介绍了有机电致发光器件(OLED的历史，结构,材料及制作工艺；分析了发光机理及性能；展望了OLED的应用前景。     

有机电致发光器件封装材料的制备研究

针对有机电致发光器件在显示器领域内的蓬勃发展和广泛应用，本论文对有机电致发光器件封装材料的制备进行了分析研究，首先分析介绍了有机电致发光的优点以及常用的封装方法，在此基础上重点探讨了封装材料的制备工艺，给出了防潮等关键技术措施，对于进一步提高有机电致发光器件封装材料的制备工艺水平具有一定借鉴指导意义。     

有机电致发光器件的效率及寿命

有机电致发光器件的效率取决于电子和空穴的有效注入和复合.电极材料和有机材料的稳定性以及电极/有机层之间的界面处的相互作用是制约有机电致发光器件寿命的主要因素.     

高效稳定性有机黄光电致发光器件

主要通过红绿磷光材料R-4B和GIr1掺杂的方法,制备了黄光OLED器件,器件结构为ITO/MoO3(X)/NPB(40nm)/TCTA(10nm)/CBP:GIr1 14%:R-4B2%(30nm)/BCP(10nm)/Alq3(40nm)/LiF(1nm)/Al(100nm),TCTA和BCP分别为电子和空穴阻挡材料,同时结合TCTA和BCP对载流子的高效阻挡作用,研究了MoO3对器件效率和稳定性的影响。发现当增加MoO3的厚度为90nm时,在较大的电压范围内,器件都具有较高的效率和色坐标稳定性。在电流密度为7.13mA/cm2时,器件达到最高电流效率29.2cd/A,亮度为2081cd/m2;电流密度为151.7mA/cm2时,获得最高亮度为24430cd/m2,电流效率为16.0cd/A;器件色坐标稳定性较好,当电压为5、10、15V时,色坐标分别为(0.5020,0.4812)、(0.4862,0.4962)、(0.4786,0.5027)。器件性能的改善主要归因于载流子注入与传输的平衡以及阻挡层对发光区域的有效限定。     

Dislocation engineered silicon light emitting devices

The influence of boron-induced dislocation loops on the luminescence efficiency of silicon-based light-emitting diodes is investigated. Luminescence measurements and transmission-electron-microscopy images from devices fabricated by boron implantation into crystalline silicon, and subsequently processed under different conditions to form dislocation loops of different size and densities, were compared. Light emitting devices were also fabricated in an otherwise identical but a pre-amorphized substrate, to prevent boron-induced loop formation. The results demonstrate a strong correlation between the dislocation loop density and areal coverage, and the light emission efficiency. The devices produced in the pre-amorphized substrate, without dislocation loops, show strongly quenched light emission.     

Red organic light emitting devices with reduced efficiency roll-off behavior by using hybrid fluorescent/phosphorescent emission structure

Organic light emitting device (OLED) with a fluorescence-interlayer-phosphorescence emissive structure (FIP EML) is proposed to solve efficiency roll-off issue effectively. By doping fluorescent emitter of 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) and phosphorescent emitter of tris(1-phenylisoquinolinolato-C2,N)iridium(III) (Ir(piq)₃) into the different regions of emission zone to form FIP EML in red OLED, an improvement of more than 20% in luminance efficiency roll-off compared with that of typical phosphorescent OLED with single EML in 10-500 mA/cm² range has been obtained. Detailed mechanisms have been studied. Such improvement should be attributed to the distinct roles of the two emitters, where DCJTB mainly used to influence the carrier transport leading to an improved balance of charge carriers while Ir(piq)₃ functions as the radiative decay sites for most generated excitons. Meanwhile, with the help of the formation of FIP EML, the redistribution of excitons in recombination zone, the suppression of non-radiative exciton quenching processes and the elimination of energy transfer loss also contribute to the enhancement of efficiency roll-off. The method proposed here may provide a route to develop efficient OLED for high luminance applications.     

Enhancing light extraction in top-emitting organic light-emitting devices using molded transparent polymer microlens arrays

The light extraction efficiency in organic light-emitting devices (OLEDs) is enhanced by up to 2.6 times when a close-packed, hemispherical transparent polymer microlens array (MLA) is molded on the light-emitting surface of a top-emitting device. The microlens array helps to extract the waveguided optical emission in the organic layers and the transparent top electrode, and can be manufactured in large area with low cost.     

Influence of ITO patterning on reliability of organic light emitting devices

Indium tin oxide (ITO) films are widely used for a transparent electrode of organic light emitting devices (OLEDs) because of its excellent conductivity and transparency. Two types of ITO substrates with different surface roughness were selected to use as anode of OLEDs. In addition, two types of etching process of ITO substrate, particularly the etching time, were also carried out. It was found that the surface roughness and/or the etching process of ITO substrate strongly influenced on an edge of ITO surface, further affected the operating characteristics and reliability of devices.     

Improvement of white organic light emitting diode performances by an annealing process

White organic light emitting diode (OLED) devices with the structure ITO/PHF:rubrene/Al, in which PHF (poly(9,9-di-n-hexylfluorenyl-2,7-diyl)) is used as blue light emitting host and rubrene (5,6,11,12-tetraphenylnapthacene) as an orange dye dopant, have been fabricated. Indium tin oxide (ITO) coated-glass and aluminium were used as anode and cathode, respectively. The devices were fabricated with various rubrene-dopant to obtain a white light emission. The OLED device that composed of several concentrations of rubrene-doped PHF film was prepared in this study. It was found that the concentration of rubrene in the PHF-rubrene thin film matrix plays a key role in producing the white color emission. In a typical result, the device composed of 0.06 wt.% rubrene-dopant produced the white light emission with the Commission Internationale de L'Eclairage (CIE) coordinate of (0.30,0.33). The turn-on voltage and the brightness were found to be as low as 14.0 V and as high as 6540 cd/m², respectively. The annealing technique at relatively low temperature (50 °C, 100 °C, and 150 °C) was then used to optimize the performance of the device. In a typical result, the turn-on voltage of the device could be successfully reduced and the brightness could be increased using the annealing technique. At an optimum condition, for example, annealed at 150 °C, the turn-on voltage as low as 8.0 V and the brightness as high as 9040 cd/m² were obtained. The mechanism for the improvement of the device performance upon annealing will be discussed.     

Highly efficient white phosphorescent organic light emitting diodes using a mixed host structure in deep blue emitting layer

Highly efficient phosphorescent white organic light-emitting diodes (PHWOLEDs) were developed using a deep blue phosphorescent emitter doped into a mixed host of high triplet energy host materials. The deep blue emitting layer was combined with a red:green emitting layer to fabricate PHWOLEDs. A high quantum efficiency of 19.5% with a color coordinate of (0.29,0.38) and 19.8% with a color coordinate of (0.39,0.46) were achieved in the PHWOLEDs using the mixed host emitting layer doped with a deep blue phosphorescent dopant. In addition, a low optimum doping concentration below 5% in red, green and blue dopants was realized in the PHWOLEDs.     

基于新型红色材料的有机发光二极管

对一种名为N，N－双－[4-2-(4-二氰甲烯基－6－甲基）－4H－吡喃－2－基]乙烯基]苯基苯胺的新型有机红色材料（BDCM）进行了薄膜发光行为的研究，此材料的一个三苯胺（给电子基）和两个二氰甲烯吡喃（受电子基）所形成的较好空间位阻和强荧光发射能力，使得其固体薄膜具有很高的红色荧光量子产率。所构成ITO／CuPc/DPPP/BDCM/Mg:Ag的红色薄膜电致发光器件，在外加19V直流电压时达到582cd/m^2的发光亮度，同时，此器件的发光色度具有不随所加电流密度变化而改变的特点，表明此材料有很好的电子传输和红色发射性能。