Applied Physics Letters · 2006 · 33 citations · 10 references
Natural SciencesChemistryMaterials ScienceElectronic MaterialsOptical MaterialsSemiconductor MaterialsHybrid MaterialsLight-emitting DiodesOptoelectronic MaterialsOrganic Electronic MaterialsOrganic SemiconductorsWide Band Gap SemiconductorsElectroluminescenceElectronic Band GapLayer Thickness EffectsOrganic ElectronicsOrganic Light-emitting DiodesOrganic Light-emitting MaterialsPhotoluminescence Quantum YieldSemiconductor Heterojunctions
Combinatorial screening of exciplex formation in blends of 4,4′,4″-tris[2-naphthyl (phenyl)-amino] triphenylamine (2-TNATA), and 2,2′,7,7′-tetrakis(2,2′-diphenylvinyl) spiro-9,9′-bifluorene (spiro-DPVBi) is described. The blended layer was incorporated in ITO/[2-TNATA]/[1:1 2-TNATA:spiro-DPVBi]/[N,N′ - diphenyl - N,N′ - bis (1-naphthylphenyl) - 1,1′ - bi-phenyl - 4,4′-diamine (NPB)]/[spiro-DPVBi]/[tris(8-hydroxy quinoline) Al]/CsF∕Al organic light-emitting devices; the thickness of the blend and NPB layers were varied systematically. The electroluminescence quantum yield decreased as the blended layer thickness increased. The NPB spacer layer reduced the exciplex formation; an 8-nm-thick layer completely suppressed it.
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