| 초록 |
Solution process such as spin-coating and inkjet-printing method has also attracted much attention due to its potential advantage of easy production for large-area lighting and extremely low production cost. However, multilayer is difficult to be made with solution process, which means low device efficiency compared to that of evaporation method. In this study, we report high-efficient single emitting layer based on co-host system by using solution process. The device configuration is as the following: ITO / PEDOT: PSS (40nm) /EML (50nm)/TPBi (20nm)/LiF/Al. Double host (NPB and TATa) and dopant (DPAVBi and Ruburene) in emitting layer were used. These devices show two-colored white emission having a CIE (0.307, 0.409). α-NPB and β-NPB were used to compare the effects of energy transfer mechanism from host to dopant. As a result, the device using α-NPB as host shows 3.87 cd/A, which leads to higher efficiency than that of device using β-NPB. |
