| Popis: |
UV-violet OLEDs based on ITO/[copper phthalocyanine]/[4,4-bis(9carbazolyl)biphenyl]/[bathocuproine]/CsF/Al, with a peak emission at ~380 nm, were fabricated and optimized using a single-batch combinatorial fabrication. The optimal device had a peak radiance of 20 W/m at 500 mA/cm with CBP and BCP thicknesses of 500 and 250 , respectively. The maximum luminance was 142.9 Cd/m o A o A 2 at 11.74 V. Adding a thin layer (1.5 nm) of NPB as hole transport layer was sufficient to degrade the UV emission. This UV performance deterioration is due to energy transfer from the wide band-gap CBP to NPB; it limits the choice of HTL materials that are usable for enhancing such UV-OLEDs. 2. |
