Design of Large Area PLEDs on Flexible Substrates: Highly Efficient Flexible Devices Using a Statistical Copolymer of Oxadiazole-Containing PPV

摘要

With polymers as the active layer on a plastic substrate, construction of flexible devices is possible, although the use of calcium cathodes places stringent requirements on the encapsulation of the device. Our work focuses on the development of polymers that will function with higher work function cathodes, making encapsulation less problematic. Additionally, we seek to fabricate stable, flexible PLEDs with a simple device configuration for military display applications. To this aim we have made efficient multi-layered flexible PLEDs using a statistical copolymer of hole transporting dialkoxy- substituted PPV with an electron transporting oxadiazole containing PPV derivative as the emissive layer. Even in single layered devices, this polymer shows good performance. When PEDOT/PSS was coated on the ITO and LiF was evaporated between the emissive layer and Al, device efficiency is improved significantly. Several other cathode materials were also screened, and those results will be reported as well.