Non‐linear charge conduction and emission behaviour of OELD fabricated with Alq3 and TPD‐doped soluble polyimide

We have attempted to investigate the non‐linear behaviour in the characteristics of organic electroluminescent devices (OELDs) fabricated with polyimide and an organometallic complex as a hole transport layer (HTL) and an emission layer, respectively. The thickness of the polyimide HTL and the kind of metal cathode were varied to study the mechanism of the charge conduction and the electroluminescence (EL). The conventional linear models well explained the voltage‐dependent charge injection and the current‐dependent EL. New non‐linear models proposed here predicted the characteristics almost completely, even though the physical meaning of the included parameters was not clearly defined. The OELD with the Mg cathode showed lower luminous efficiency in the high electric field than that with the Al cathode because of poor adhesion between Mg and Alq3. The maximum luminous efficiency was ca. 1.2 lm/W at 700 cd/m² in the case of the Al cathode. The emission colour did not change for the OELD with the Mg cathode irrespective of the polyimide HTL, whereas the OELD with the Al cathode and the thick HTL showed a red‐shifted EL of ca. 10 nm. Copyright © 2000 John Wiley & Sons, Ltd.     

平板显示器件技术与进展

阐述了各类显示器件目前的技术发展状况，着重介绍了等离子体显示器、有机电致发光器件、场致发射器件和液晶投影等。     

White light emission obtained by direct color mixing in multi-layer organic light-emitting devices

Three different structures of multi-layer organic light-emitting devices, which consisted of two emitting layers separated by a carrier blocking layer, were investigated. Since the emitting layers are constructed to emit different colors, the colors emitted from the structures are mixed. It was found that the colors were directly mixed in the structures of this study due to the carrier blocking layer sandwiched by the two emissive layers. The blocking layer splits the carrier recombination zone, and with the emission color is controlled by balancing the split. For the white light the CIE coordinate of (0.30, 0.33) is obtained at an applied voltage of 14 V. The luminance is measured to be 1,000 cd/m² at 14 V. with the power efficiency of 0.4 lm/W. For a luminance of 100 cd/m² at 11 V., the CIE coordinate is found to be (0.31, 0.34) and the power efficiency was as high as 0.53 lm/W.     

平板显示器产业化进展及发展趋势

从现在起,到2010年,FPD将以年均33%的速度增长。韩国第8代(2500mm×3000mm)生产线将于2007年投产,2004后半年台湾地区的TFT-LCD产能有可能居世界首位。PDP厂家纷纷扩大生产规模,PDP将成为大型彩电的主流,本文介绍了世界范围内平板显示器产业化进展和发展趋势。面对机遇和挑战,对我国发展平板显示器产业战略提出建议。     

有机电致发光彩色平板显示器

由于有机电致发光器件具有驱动电压低，亮度高，全彩色化及成本低等优点，因此，近年来用它制作平板显示器的工作备受关注。下文论述了彩色有机发光器件平板显示器的发展现状。     

OELD技术及市场发展前景探究

介绍了OELD的应用、技术特点,影响OELD性能与寿命的关键技术,近年来技术及市场状况,分析了OELD专利许可状况并提出了我国应采取的对策,预测了OELD产业在全球的发展前景。     

Cesium-incorporated indium-tin-oxide films for use as a cathode with low work function for a transparent organic light-emitting device

Transparent organic light-emitting devices (TOLEDs) were successfully fabricated utilizing a novel transparent conducting cathode with low work function. Cesium-incorporated indium-tin-oxide film was deposited on the organic layers with negligible damage by simultaneous operation of RF magnetron sputtering using an ITO target and vacuum evaporation of metallic cesium. Incorporation of cesium in the ITO film was confirmed by XPS analysis. The work function (4.3 eV) determined by photoelectron spectroscopy in air (PESA) was lower than that of 0.3-0.4-eV without cesium-incorporation and stable under the atmospheric environment. The electron injection efficiency of cesium-incorporated ITO cathode in the present transparent OLED fabricated was comparable to that of the previous double-layered structure comprising of ITO cathode and an organic buffer layer (BCP) doped by evaporation of cesium [T. Uchida, S. Kaneta, M. Ichihara, M. Ohtsuka, T. Otomo, D.R. Marx, Jpn. J. Appl. Phys., 44, No. 9 (2005) L282].