Taking OLEDs to Unexplored Frontiers

Conventional OLEDs are limited to thin transport layers and special electrode materials and/or pre-treatment due to the following restrictions: The conductivity of the charge carrier transport layers is low, leading to    ohmic losses. The injection of charge carriers from the electrodes into the transport layers    has a high barrier, leading again to an additional driving voltage increase. The organic stack of doped and undoped OLEDs is similar. In contrast to conventional OLED, Novaled PIN OLEDTM introduces an additional degree of freedom when it comes to product design. Hole and electron-transport as well as charge carrier injection are dramatically enhanced using Novaled PIN technology. As a result of doping, additional process steps, such as ITO treatment, are not needed. Additionally, a much wider range of materials used for the anode and cathode becomes available using p and n doping. In combination, this results in a very low driving voltage and high substrate compatibility of the Novaled PIN OLEDTM. Meanwhile the highest possible power efficiency and the longest possible life-time are maintained. Novaled has developed a number of doping and transport materials to be used in organic OLEDs to further enhance and support the already existing advantages. Furthermore Novaled uses a number of different interlayers and emitter materials, which can be easily integrated into Novaled's PIN structure. The principle architecture of a bottom emission OLED incorporating the intrinsic emission layers into the Novaled PIN OLEDTM technology by using doped transport layers: holes are injected from the anode and transported by p-hole transport layer (p-HTL) to the emitting layer (EML). Electrons are injected from the cathode and transported by the n-electron transport layer (n-ETL). Recombination of the charge carriers takes place in the EML and light is emitted.