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White Organic Light-Emitting Diodes with fine chromaticity tuning via ultrathin layer position shifting

Hakim Choukri·Alexis Fischer·Sebastien Forget·Sebastien Chenais·Marie-Claude Castex·Dominique Ades·Alain Siove·Bernard Geffroy
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Abstract

Non-doped white organic light-emitting diodes using an ultrathin yellow-emitting layer of rubrene (5,6,11,12-tetraphenylnaphtacene) inserted on either side of the interface between a hole-transporting NPB (4,4'-bis[N-(1-naphtyl)-N-phenylamino]biphenyl) layer and a blue-emitting DPVBi (4,4'-bis(2,2'-diphenylvinyl)-1,1'-biphenyl) layer are described. Both the thickness and the position of the rubrene layer allow fine chromaticity tuning from deep-blue to pure-yellow via bright-white with CIE coordinates (x= 0.33, y= 0.32), a external quantum efficiency of 1.9%, and a color rendering index of 70. Such a structure also provides an accurate sensing tool to measure the exciton diffusion length in both DPVBi and NPB (8.7 and 4.9 nm respectively).

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Hakim Choukri, Alexis Fischer, Sebastien Forget, Sebastien Chenais, Marie-Claude Castex, Dominique Ades, Alain Siove, Bernard Geffroy. 2006-09-27. White Organic Light-Emitting Diodes with fine chromaticity tuning via ultrathin layer position shifting. https://doi.org/10.1063/1.2382730

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