The effects of electron injection layers on magnetoconductance and magnetoelectroluminescent in polymer light emitting diodes

• Main Authors: Jin-HanWu, 吳晉翰
• Other Authors: Ten-Chin Wen
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/06576443466495050594

碩士 === 國立成功大學 === 化學工程學系碩博士班 === 100 === In this thesis, the study is focus on effects of electron injection layers on magnetoconductance (MC) and magnetoelectroluminescent (MEL) in polymer light emitting diodes. By the change of electrical properties, we could infer the effect on exciton and carrier in the devices with magnetic field. Further, we could investigate the mechanism of electron injection layers. In the experiment, we used tetraoctylammonium bromide, lithium fluoride and sodium borohydride as electron injection layers to fabricate devices. We compared electrical properties between devices with electron injection layers and without electron injection layers. The results show that electron injection layers do enhance the current density of devices and increasing the external quantum efficiency. To study the mechanism of electron injection layers, we put devices on magnetic field measuring electrical properties. This result demonstrated that current and brightness of device are dependent on magnetic field and the curves are different with electron injection layers. To unravel the meaning of curves, we used fitting method to simulate curves of MC and MEL at different bias than deducing the physics phenomenon from the result of simulation. From the result of simulation, there are main effects on MC and MEL curves. First one is intersystem crossing between excitons. Second one is exciton-charge interaction. The last one is trap –charge interaction. In the final, we determined the effects of device with different electron injection layers from the three mechanisms.