Photonic crystal slabs in flexible organic light-emitting diodes

(整期优先)网络出版时间:2015-02-12
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Photoniccrystalslabsintegratedintoorganiclight-emittingdiodes(OLEDs)allowfortheextractionofwaveguidemodesandthusanincreaseinOLEDefficiency.WefabricatedlinearBragggratingswitha460-nmperiodonflexiblepolycarbonatesubstratesusingUVnanoimprintlithography.Ahybridorganic–inorganicnanoimprintresistisusedthatservesalsoasahighrefractiveindexlayer.OLEDscomposedofapoly(3,4-ethylenedioxythiophene)polystyrenesulfonate(PEDOT:PSS)polymeranode,anorganicemissionlayer[poly(p-phenylenevinylene)(PPV)-derivative'SuperYellow'],andametalcathode(LiF/Al)aredepositedontotheflexiblegratingsubstrates.TheeffectsofphotoniccrystalslabdeformationinaflexibleOLEDarestudiedintheoryandexperiment.Thesubstratedeformationismodeledusingthefinite-elementmethod.Theinfluenceofthechangeinthegratingperiodandthewaveguidethicknessunderbendingareinvestigated.Thechangeinthegratingperiodisfoundtobethedominanteffect.Atanemissionangleof20°achangeintheresonancewavelengthof1.2%ispredictedforastrainof1.3%perpendiculartothegratinggrooves.ThisvalueisverifiedexperimentallybyanalyzingelectroluminescenceandphotoluminescencepropertiesofthefabricatedgratingOLEDs.