Improving the Performance of a Hybrid Inorganic–Organic Light-Emitting Diode Through Structure Optimization

摘要

Significant performance enhancement of a green hybrid inorganic-organic light-emitting diode (HyLED) based on a simplified ${hbox{WO}}_{3}$/organic layer structure has been achieved through structure optimization. A 20–50 nm as-deposited ${hbox{WO}}_{3}$ layer allowed for facile hole injection and transport. In the meantime, it had high transparency and good robustness required for efficient and reliable operation of the HyLED. Inserting a 30 nm undoped 4,4 $^{prime}$-N,N $^{prime}$-dicarbazolebiphenyl (CBP) layer between the ${hbox{WO}}_{3}$ and emitting layer resulted in a broadened exciton generation zone and improved the brightness by 87.4% at 20 ${hbox{mA/cm}}^{2}$. At this injection level, the optimized HyLED reached a luminance of 11642 ${hbox{cd/m}}^{2}$ and a current efficiency of 58.2 cd/A, and exhibited good reliability under constant-current stressing.