Research On Optical And Electrical Properties Of ITO/NPB/Alq₃/LiF/Al Oled

Organic light-emitting device have series of advantages: their manufacture process are simple and they have wide-viewing angle, short response time, light weight, high brightness, all-solid-based construction and they are able to be flexibly and full color displaying, so they are highly competitive in the field of flat panel display and considered to be the mainstream flat-panel display technology in future and they have attracted more and more attention. After several decades in development, electroluminescent technology has been becomming mature. The stability, life etc of OLED are more or less poor, therefore, researchers all over world have made great efforts to optimize the performance of OLED.This article mainly studies two new multi-layer light-emitting devices, whose content covers electroluminescence mechanism, preparation, and optical and electrical properties of these devices, introduced properties of different light-emitting materials, structure of OLED, and theoretical model of light-emitting. This experiment made use of multi-source organic molecular vapor phase deposition system and improved production process of this system. Prepared ITO/NPB/Alq₃/LiF/Al multi-layer organic light-emitting device, tested current-voltage characteristic, Brightness-voltage characteristic and electroluminescence spectra of the device. When the applied voltage is 14V, the current of device achieves 4.5mA; the brightness of device reached 3100cd/m2; When the applied voltage is 12V,the pectrum peak of device is at 528nm. Prepared and tested ITO/m-MTDATA/NPB/Alq₃/LiF/Al organic light-emitting device, Compared ITO/NPB/Alq₃/LiF/Al with ITO/m-MTDATA/NPB/Alq₃/LiF/Al organic light-emitting device in optical and electrical properties. When the applied voltage is 14V, the current of the ITO/m-MTDATA/NPB/Alq₃/LiF/Al OLED is 78.0mA; when the two devices are at the same working voltage 11V, the brightness of ITO/m-MTDATA/NPB/Alq₃/LiF/Al OLED reaches 19200cd/m² and the brightness of ITO/NPB/Alq₃/LiF/Al is only 190.0cd/m²; When the applied voltage is 12V, the electroluminescence spectra's peak of two devices are at the same location, they are located at 528nm.