The main steps of OLED device production

The organic film and metal film of OLED devices will immediately oxidize and deteriorate when exposed to water and air, so measures must be taken to avoid this problem. Inorganic film protection can be used. Inorganic film protection materials include silicon nitride, magnesium fluoride, indium oxide, etc. Inorganic protective film materials are prepared by resistance heating or magnetron sputtering. After the protective film is formed, the manufactured device is packaged. The packaging process must be carried out in an inert gas without water and oxygen. The packaging materials include adhesives and covering materials. The adhesive uses UV-curing or heat-curing epoxy curing agent, and the covering material uses a glass cover. A desiccant is added to the cover to absorb residual water.

The first company to develop this technology was TDK of Japan. The light emitted by the white light device is colored by a color filter. The color filter is expensive and has low luminous efficiency. Although this mode can achieve high color purity, the aging characteristics of the red, green and blue light devices are different, and the color purity will change over time.

The encapsulated OLED device must be characterized by performance tests , mainly the luminous brightness -voltage curve and the current density-voltage curve. The steeper the curve rises, the faster the luminous brightness rises with voltage and the current density rises with voltage, and the higher the luminous efficiency will be.