| Top-emitting organic light emitting diodes (TOLEDs) own higher luminance, higherefficiency and high transmittance, which have attracted much attention in industry andacademic community. Based on the transfer matrix method and the orthogonal analysismethod, we designed and optimized the parameters and structures of fluorescent andphosphorescent TOLEDs to obtain high efficiency and high transmittance TOLEDs devices.We also evaluate theluminescence performance and analyzed the influencing factors for theas-prepared TOLEDs. The main research content as follows:1．Calculated and optimized the device parameters of MoO3/Ag/MoO3transparentanode based fluorescent TOLEDs with the best performance. Then the TOLEDs with theoptimized structure were fabricated to verify the accuracy of the simulated results Thefluorescent TOLED with the electrode of MoO3(10nm)/Ag(10nm)/MoO3(25nm) possessesthe highest performance.. The maximum transmittance is88.26%at the peak of532nm. Andthe maximum luminance and luminous efficiency are20076cd/m2and4.03cd/A, which areimproved by18.5%and56%, respectively. And the phosphorescent TOLED with thestructure of Al/LiF/Bphen/CBP:8wt%Ir(ppy)3/NPB/MoO3/Ag/MoO3was fabricated by thesame method. The phosphorescent TOLED with the electrode of MoO3(10nm)/Ag(10nm)/MoO3(25nm) exhibits the highest performance. The maximum transmittance is88.88%.And the maximum luminance and luminous efficiency are52457cd/m2and32.5cd/A. whichare improved by110%and47%respectively. Improvement of the device performance wasattributed to the high stability of MoO3/Ag/MoO3electrode, which can effectively improve the ability of hole injection. Finally, using MoO3(10nm)/Ag(10nm)/MoO3(25nm) aselectrode, tricolor phosphorescent TOLED were fabricated, and the luminous performancewas increased by comparing with the traditional phosphorescent OLED.2. On the basis of experimental results above, we investigated the effect ofm-MTDATA as the hole-injection materials in the transparent anode, which has the similarenergy level, transmittance and hole-injection ability with MoO3. The device structure wasAl/LiF/Bphen/CBP:8wt%Ir(ppy)3/NPB/m-MTDATA/Ag/MoO3. We found thatphosphorescent TOLED with the electrode of m-MTDATA(10nm)/Ag(12nm)/MoO3(25nm)exhibits the highest performance. The maximum transmittance is87.88%. And the maximumluminance and luminous efficiency are59743cd/m2and27.5cd/A, which are improved by139%and22.4%, respectively.The device also shows high brightness under a low voltage.3. Finally, we also optimized and fabricatd the phosphorescent TOLEDs with HAT-CNas hole-injection material. The device structure isAl/LiF/Bphen/CBP:8wt%Ir(ppy)3/NPB/HAT-CN/Ag/MoO3. We found that phosphorescentTOLED with the electrode of HAT-CN(10nm)/Ag(12nm)/MoO3(25nm) shows the highestperformance. The maximum transmittance is85.19%. And the maximum power andluminous efficiency are14.3lm/W and23.2cd/A, which are improved by13%and5%,respectively. The device efficiency roll-offs are not obvious, it still exhibits high efficiencyunder high current density. |
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