When the OLED energy, metal cathode generates electrons, ITO anode to generate holes, to do with all the electric force, the electrons pass by way of the electron transport layer, a hole through the hole transport layer, towards the organic light emitting layer meet, electrons and holes are positively charged and negatively charged, they are attracted to one another, in the appeal (Coulomb force) action to be tied with each other, yin and yang combine to type excitons. Exciton excited luminescent molecules, to ensure that the power on the light-emitting elements raise, in an excited state, and in an excited state with the molecule is unstable, it wants to return to a steady state, in a incredibly quick time period, it releases power back to a stable state, And around the issue of energy released inside the form of light, on account of the ITO anode segment is transparent, people can see the light it emitted a. Television screen to bring us a visual feast, not with only 1 colour, and distinct colors are produced of distinct material for the organic light-emitting layer triggered.
OLED have such great functionality, it's tips on how to make out? Right here a short overview of this method amongst the least bit. Excellent functionality of organic light emitting device prepared employing a number of sophisticated equipment necessary, the require to get a clean atmosphere, if doable, must be carried out within the laboratory or workshop in clean. Initial prepare very good conductivity and light transmission properties in the conductive glass, ordinarily ITO glass, ITO glass and photolithography, a high-performance ITO glass substrate; secondly will have to rigorously cleaned ITO substrate. Then evaporated organic thin film deposition and also the cathode; and ultimately to get rid of the device do packaging and testing. Amongst them, evaporation deposition from the organic thin film is really a crucial technology. An organic thin film vapor deposition system include vacuum thermal evaporation, organic vapor deposition approach, a spin coating technique and an inkjet printing method.
Vacuum thermal evaporation deposition course of action can be a standard modest molecule OLED. Till now, the longest life expectancy OLED is produced of vacuum thermal evaporation course of action made. For this reason, today's smaller molecule OLED establish prospects for commercialization of OLED displays. ITO glass substrate being cleaned, the vacuum chamber must be placed on the sample holder, the alignment beam source, at this time, ITO glass corresponds towards the target, the beam source in the evaporated organic molecules can be a bullet, where, bullet can not hit the target center, but to evenly hit the target. This process can be a bit like a piece of glass into a cup filled with hot water in the mouth on the cup, you can gradually see a layer of white mist on the glass, but the conditions here are considerably necessary to be harsh.
Just before the deposition approach of vacuum film 1st eligible, it need to be higher than the degree of vacuum is usually 10-3Pa, if less than the degree of vacuum, the vacuum chamber includes a specific concentration of air, there is going to be some gas molecules, organic molecules after injection, aspect with the organic molecules will collide with all the gas molecules, like two balls collide, organic molecules might be bounced to transform the original path of motion, which can not hit the ITO glass substrate. The organic molecules is deposited around the substrate to price uneven, simple to kind irregular arrangement, resulting in defects or pinholes. At the similar time also bring about other complications: waste materials, scattering out of organic molecules cause cavities contaminated film will air molecules and also other impurities. When you need greater overall performance OLED, it needs ultra-high vacuum organic molecular beam deposition (OMBD) program, in such a program, the degree of vacuum reached 10-6Pa or 10-7Pa magnitude. But the heat of evaporation deposition resulting from restrictions by the vacuum chamber size, can not be produced huge area OLED screen.