| 초록 |
There has been ongoing dispute about realization of blue phosphorescence materials for full-fledged application for AMOLEDs. To guarantee sufficient life time, much effort has been exerted not only on the material design but also on the optimization of the device structure. Color coordinates of 0.15 and 0.15, respectively, and power efficiency greater than 15 lm/W with lifetime of 15,000 h would be the minimum requirement. Material specifications of wide band gap (＞2.8 eV), higher charge mobilities, and thermal stability are of uttermost importance. Along the line, we have developed suitable common layers of hole and electron and emitting materials of host and dopant; we found charge mobilities differentiate device performance as well as stability of the device. Detailed investigation on solid state emission behavior as well as photodynamic studies will be elaborated. Also, for the high performance deep blue phorsphorescence, understanding of photo-deactivation mechanism is indispensable. To this end, TDDFT calculations along with electrochemical studies that enable to estimate T1 or T2 state will be presented. |
