有机/无机复合矩阵显示屏

Since C.W. Tang and his colleagues first reported bright emission from a tris 8-hydroxyquinolinato aluminum(Alq3)/diamine bilayer structure, organic light-emitting diodes (OLEDs) have been studied extensively for its application background of active elements in flat-panel color displays. The production of OLED displays will offer numerous advantages over the two primary competing display technologies: liquid crystal display(LCD) and inorganic light emitting diode(LED). The main advantages of OLED display include following:thinner form factor, less weight, resistance to fracture, light emitting display, lower overall power consumption, wide viewing angles, good contrast ratio, high efficiency, extreme fast response time, high resolution and lower fabrication cost. Attributing to its numerous advantages, OLED display can be used in mobile telephones, digital panel meters, vehicular dashboards, analytical instruments, test equipment and portable computer. OELD is thought as most potential panel display technology. For its excellent application background, many companies and research groups join the competition for the fabrication of OEL display. Great effort has produced impressive results. Up to date, external efficiencies for OLEDs exceed 21 lm/W, and extrapolated lifetimes of more than 100,000 hours at a starting brightness of 100 cd/m2 appear to be attainable. Despite this progress, full optimization of commonly used OLED structures remains elusive. There are still many problems to resolve for the fabrication of OEL display. There are still many argument to the mechanisms concerned OEL. The very low carrier mobility still limits the application of organic materials in some fast optoelectronic devices. The probes to OEL have been continued. .Many research results showed that inorganic electrode modification layers such as SiO2, CaO and LiF3 can efficiently improve the characteristics of OEL devices. Substantial energy barriers are present at the electrodes, which means that device performance is often injection-limited, especially at the low voltages desired for display applications. The mismatch of barriers for different carriers, the difference of charge-carrier mobilities and the variety of electrical field distribution result in an imbalance in electron and hole concentrations in the emission layer. For the reason of imbalance, electrons and holes are often lost to the opposite contacts before they recombine radiatively. In order to overcome these deficiencies, some concept from inorganic semiconductor device technology were applied and extended. It is known that insulating layers sandwiched between the metal electrode and the semiconductor of a conventional Schottky diode can significantly enhance minority carrier injection MIS structure. The reason for this is a reduction of the energy barrier at the Schottky contact caused by the voltage drop across the insulating layer during operation. As a consequence, light output is markedly intensified. This concept has recently been successfully applied to OLEDs, and improvements in efficiency of more than a factor of 30 have been reported. .In this project, some inorganic materials were used as electrode modulation layers, charged-carrier transport and charged-carrier barrier layers to fabricate the hybrid EL devices from organic and inorganic materials. By choosing inorganic materials with suitable properties, these inorganic materials allow us to balance the injection, transport, and recombination processes in complex multilayer OLEDs. Depending on this project, some useful results were obtained. These results can provide some useful help .a. The different inorganic semiconductors and insulators, such as CdS, ZnS, MgF2, LiF3and TiO2 were used as carrier-transport, carrier-barrier and electrode modulation layers to fabricate the electroluminescent devices based on the hybrid of organic and inorganic materials. .b. Our research results showed that ultrathin inorganic layer could efficiently prevent from formation of exciplex in the interface b

利用P型和N型半导体材料代替有机薄膜发光二极管中的电子转移和空穴转移材料，同有机发光材料构成异质结，制备有机/无机复合式矩阵电致发光显示屏。此显示屏可以充分发挥两种材料的优势，实现优势互补，提高矩阵电致发光特别蓝光的亮度，增加器件使用寿命。本项目的实施将推动电致发光显示技术的实用化进程。.