A simple method of fabricating out-coupling structures was demonstrated via solution-processing to enhance light extraction from organic light-emitting diodes (OLEDs). Scattering layers were easily obtained by spin-coating an SiO2 sol solution that contained TiO2 particles. By introducing the scattering layer and the solution-processible corrugated structure as internal and external extraction layers, the OLEDs showed increased external quantum efficiency without a change in the electroluminescence spectrum compared to conventional devices. Using these solution-processible out-coupling structures, nearly all-solution-processed OLEDs with enhanced light extraction could be fabricated. The light extraction enhancement is attributed to the suppression by the out-coupling structures of the light-trapping that arose at the interface of the glass substrate and the air.
Bibliographical noteFunding Information:
This research was supported by the Basic Science Research Program of the National Research Foundation of Korea (NRF), which is funded by the Ministry of Education, Science, and Technology (CAFDC-20120000821). This work was supported by the collaborative R&D program with technology advanced country “Development of materials and stacked device structure for next-generation solar cells, 2010-advanced-B-105” by the Ministry of Knowledge and Economy.
- corrugated structure
- light extraction
- organic light-emitting diodes
- scattering layer