The Research Of Fabrication And Process Optimization On Organic Light-emitting Diodes

Organic light emitting diode?OLED?has broad application prospects which has great advantages such as wide viewing angle,high contrast,lower power consumption and so on.Although this research field has been developing well,there are still some shortcomings in monochromatic devices and white devices,which require process optimization to improve device performances.The fabrication and process optimization of devices were studied in the following three aspects.1.Based on the orange emitting material,?fbi?₂Ir?acac?,the energy-matching host materials Tc Ta and Cz Si were used to fabricate devices with single-light-emitting layer?EML?and double-EMLs,respectivelly.The doping concentrations and thickness of EMLs were optimized,respectivelly.When the doping concentration and the EML thickness were 2 wt% and 10 nm,respectively,the double-EMLs device achieved the best performances.The maximum brightness,current efficiency,power efficiency and external quantum efficiency were 22312 cd/m²,45.12 cd/A,36.33 lm/W and 17.0%,respectively.2.Complementary white OLEDs were fabricated with double-EMLs by combining?fbi?₂Ir?acac?with a blue phosphorescent material which was FIrpic.The device performances were improved and the range of Commission Internationale de l'Eclairage?CIE?variation was reduced by optimizing doping concentrations of?fbi?₂Ir?acac?and FIrpic,respectively.The maximum current efficiency and external quantum efficiency of white device with best performances were 62.29 cd/A and 25.8%,respectively.The device with the smallest CIE variation range has a CIE of?0.339,0.395?at 10 m A/cm².3.The process optimization of blue fluorescent DBz A devices was studied by using a complementary host material Cz Si.The device performances were improved by optimizing the doping concentrations of DBz A and Cz Si.When the DBz A and Cz Si doping concentrations were 16 wt% and 6 wt%,respectively,the device achieved the best performances.The maximum brightness,current efficiency,external quantum efficiency,and power efficiency of the best device were 28009 cd/m²,7.51 cd/A,6.8%,and 7.60 lm/W,respectivelly.