1. Field
Exemplary embodiments relate to display technology, and, more particularly, to organic light emitting displays and methods of manufacturing the same.
2. Discussion
Conventional organic light emitting devices typically include two electrodes and an organic emission layer disposed therebetween. One of the two electrodes injects holes and the other injects electrons into the organic emission layer. The injected electrons and holes are combined to form excitons that emit light as discharged energy. It is noted that the organic emission layer may be configured to emit the light in at least one range of wavelengths, such as, for example, red, green, and blue color wavelengths. To this end, various methods may be utilized to fabricate such organic emission layers, such as, for instance, laser induced thermal imaging and laser-induced sublimation transfer techniques.
Laser induced thermal imaging (LITI) is a laser addressed thermal patterning technique for exposing a mask pattern with a laser beam to generate a patterned laser beam that is irradiated onto a donor film including a base film and a transfer layer. Exposed regions of the transfer layer may be released from the transfer layer, and, thereby, adhered to a portion of the organic light emitting display to form an emission layer of the organic light emitting display. It is noted that LITI enables each emission layer to be precisely patterned and placed using a “dry” manufacturing process.
Blue organic emission layers, however, may be vulnerable to heat transfer, which typically occurs when a blue organic emission layer is irradiated with the patterned laser beam. As such, blue organic emission layer may be vacuum deposited on a larger surface than intended for the blue organic emission layer. That is, when forming an organic light emitting layer using LITI, a blue organic emission layer may be formed in association with other colored pixels, such as red pixels and green pixels, in addition to a blue colored pixel. This may be referred to as an organic light emitting display including a blue common layer (BCL) structure. It is noted, however, that the red organic emission layer and the green organic emission layer may require higher driving voltages due to the presence of the blue organic emission layer formed thereon. In this manner, luminous efficiency may be decreased and life-span may be deteriorated.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
USPTO Backgrounds
USPTO Backgrounds