발광층에 분산된 Dielectric particle의 표면상태에 따른 OLED의 발광 특성

Abstract

For similar effect of plasmon, we used space charge by embedded dielectric particle. The difference of the surface charge distribution might be changed because of the charge injection and device operating characteristics. So, we created certain scratches on the surface of embedded dielectric particles and used these to control the surface charge distribution. We prepared three solutions which has different stirring time of BaTiO3. The dopant BaTiO3’s stirring time were 6hours, 9hours and 12hours. Single layer of ITO/BaTiO3@PFO/Al device was made by using this solution. We measured applied voltage versus current and luminescence characteristics. The stirring time much longer, even the BaTiO3 particle has been grinded. At that time, grinded BaTiO3 particles were recombination each other and particles size was growth. Consequently, Dielectric particle’s effect will not occur. For this reason, the selection of a suitable stirring time is necessary. The luminescence characteristics were much better and we could observe an increasing green band. This effect appeared by PFO excimer and trap assisted recombination's improvement of embedded BaTiO3. Just embedding BaTiO3 in PFO layer, color conversion effect that blue + green was observed. If we use these improvements in current & luminescence characteristics and color conversion effects, it expected to be helpful for study of White OLED.