Microcavity Electroluminescent Optical Devices

The basic organic light-emitting device(OLED) consists of a number of ultra-thin organic layers between two electrodes. It has the characteristic of self-light-emitting, full-color display, high brightness, high contrast, low voltage(-5V~20V), low power-consume, light and thin(it's volume and weight is only 1/3 of LCD, high light-emitting efficiency, fast response, broad visual angle, single slice structure, simple craftwork, low cost, can be fabricated on soft underlay, flectional and folding and so on. After C.W.Tang reported two layers purification small molecule thin film electro-light-emitting organic diode with high efficiency in 80's and Burroughes reported polyer electro-light-emitting in 1990, OLEDs have achieved flying development and have the competition of becoming the leading of next display. Optic microcavity arouses great interest in condensed state physics. It can change characters of spontaneous emission, such as spectral full width at half-maximum, light-emitting intensity at peak and so on. Inducting the optic microcavity into OLEDs, it can change the spectral of organic elctro-light-emitting film, narrow the spectral width and obtain good homochromatism light-emitting; if the microcavity's structure is designed reasonably, the emitting wavelength will be controlled effectively and the light-emitting efficiency can be heightened. ITO thin film is usually used as the transparency electrode of organic light-emitting device. There are many methods to fabricate ITO thin film such as split, heat aggradation, chemic gas aggradation, electron beam evaporation, spay heat decompound, micro-latex, sol-gel and so on. Comparing the sol-gel method with other methods, it has the following virtue: the consistency and uniformity can be controlled easily, the craftwork is simple, the temperature of craftwork is low, the price of the raw and processed materials is cheaper, the cost of the equipments is cheap, the film can grow on both of the two surface of the underlay and can easily grow film with broad area, et al. This article introduced the research actuality of OLED,the microcavity theory and application and the thin film optic theory. Detailed all kinds of microcavity effects of microcavity OLED(MOLED) and the calculating program .