Research On Large Area Uniform Illumination OLEDs Device Based On Conductive Laterally And Transparent Electrode

With the need for sustainable development of the world economy and the increasing problem in global carbon emissions,energy conservation has become particularly important.Organic Light-Emitting Diodes(OLEDs)have begun to be used in large scale in the field of display and illumination due to their inherent energy-saving advantages.In addition,OLEDs,in applications for display and illumination,also have the advantages of flexibility,fast response,high display contrast,and low blue light damage to human eyes.In the structural composition of OLEDs,transparent conductive electrodes are a particularly important layer.The research subject of this thesis is to develop transparent conductive electrodes.A large-area uniform OLEDs device was manufactured based on a laterally extended conductive metal oxide/metal laminated transparent electrode structure.In this thesis,two research works have been conducted:OLEDs with LMO(Laminated Metal Oxide)structure of MoO3/Al periodic structure and MoO3/Mg/MoO3 structure are fabricated for use in OLEDs with LMO structure of MoO3/Al/MoO3.1.OLEDs devices with LMO structure of MoO3/Al periodic structure were prepared.It was found that the OLEDs fabricated by the partitions did not emit light uniformly.Therefore,the device was separately fabricated,and finally a large-area uniform OLED device was obtained,and the three-repeated LMOs OLED device had the best electrical performance.2.OLEDs devices with LMO structure of MoO3/Mg/MoO3 were prepared.By optimizing the thickness of each layer in LMO structure,a large-area uniform OLED device was successfully fabricated,and the highest current efficiency was 50.95 cd/A,and the highest power efficiency was 34.5 lm/W.The turn-on voltage is 2.8V.Compared with the OLEDs of MoO3/A1/MoO3 structure as the anode,similar in EL spectrum with half width is 61nm have been obtained.By measuring the sheet resistance of the periodic structure of MoO3/A1 and the MoO3/Al/MoO3 structure,the sheet resistances in both cases are much higher than that of the traditional transparent conductive electrode.The reason why the OLEDs device can still work normally is that,under the electric field of the cathode Al,holes can be laterally conducted between the grid Al through the LMO structure,and then injected into the organic layer through the LMO structure then illuminate by compositing with the electrons injected from the cathode.SEM and XPS results show that MoO3 and Mg react chemically in the laminated MoO3/Mg/MoO3,which is a good transparent conductive electrode.