Tham khảo tài liệu 'organic light emitting diode part 9', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 153 Optimum Structure Adjustment for Flexible Fluorescent and Phosphorescent Organic Light Emitting Diodes Al 65nm has a maximum luminance efficiency of cd A by optimizing organic layer thicknesses. This device performance improvement is attributed to increased hole injection and improved hole-electron balance. In addition extending the charge carrier recombining area and using more suitable HBL material and suitable thickness of its thin film will gradually increase and improve the luminance efficiency of the device. Comparing devices with TPBi and BCP as the HBL it was found that devices fabricated with TPBi as the HBL exhibited better luminance efficiency than BCP. We also discussed the effect with without a spin-coated buffer layer on device performance. It was found that devices inserted with a spin-coated buffer layer had better brightness luminance efficiency and lifetime than conventional devices without spin-coating buffer layer . Furthermore the research demonstrated the advantage of using spin-coating codoping NPB a-NPD THF exhibit the similar p-type doping properties and metal-like Ohmic contact interface plus thermal-evaporation in fabricating flexible fluorescent organic light emitting diodes with double-hole transport layer structures. The performance of the best Device G1 exhibited a luminance of 4634 cd m2 at 9 V and a luminance efficiency cd A at 68 mA cm2. Compared with the single thermal-evaporated NPB only HTL structure the luminance efficiency of device with spin-coated NPB a-NPD THF as buffer layer was increased by about cd A and its half-lifetime was increased by about 41 longer than the device without spin-coated buffer layer. 5. References 1 C. W. Tang and S. A. VanSlyke 1987 . Organic electroluminescent diodes. Appl. Phys. Lett. Vol. 51 pp. 913-915. 2 Z. Liu J. Pinto J. Soares E. Pereira 2001 . Efficiency multilayer organic light emitting diode. Synth. Met. Vol. 122 pp. 177-179. 3 Y. Shirota Y. Kuwabara H. Inada T. .
