Performance improvement for organic light emitting diodes by changing the position of mixed-interlayer

Abstract

Organic Light-Emitting Diode (OLED) is presently the most sought-after display technology. It provides low-cost, flexible, rollable displays in addition to wide viewing angles and excellent colour qualities. Still, the organic displays have not reached at their best performance and there is a lot of scope for improvement in their performance. In addition to the injection layer, emission layer, transport layer, etc, researchers are looking forward to the charge carrier transport layer, spacer layer, mixed interlayer, etc. to further enhance the device performance. In this article, a depth analysis related to the impact of the position of the mixed interlayer is performed to analyze the impact on device performance. It is observed that on shifting mixed interlayer (MI) towards the cathode; luminescence and current density depict depreciation. However, on shifting MI towards anode there is a significant performance improvement. The complete analysis includes seven device structures, wherein the position of MI is varied. The best performing device depicts luminescence of 17139 cd/m2 and a current density of 84.6 mA/cm2, which is 40.05% higher for luminescence and 111.5% for current density than that of reference device. Additionally, the internal analysis of device structure is thoroughly evaluated using the cut line method to better understand the internal device physics in terms of the electric field, electron concentration, total current density, Langevin’s recombination rate, and Singlet exciton density.