• Journal of the Korean Ceramic Society
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• v.38 no.12
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• pp.1085-1092
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• 2001

The high efficient AC powder EL devices classified by low cost and low power consumption type fabricated using screen printing method with film thickness and organic binder. Brightness and current density were measured at frequency range of 400Hz∼1kHz and voltage range of 50∼300V$\_$rms/ to estimate optoelectrical properties of AC powder EL devices, respectively. Frequency generator was used as system producing frequency and voltage of a sine wave. Also brightness and current density were measured by luminometer and multimeter. In the case of low cost type AC powder EL device, brightness and current density were about 43 cd/m$^2$and 20$\mu$A/cm$^2$when the thickness of phosphor and dielectric layer was 45∼50$\mu$m under no addition of plasticizer respectively. In the case of low power consumption type AC powder EL device, brightness and current density were about 74 cd/m$^2$and 30∼40$\mu$A/cm$^2$when the thickness of phosphor and dielectric layer was 45∼50$\mu$m and 15∼20$\mu$m under addition of 15wt% plasticizer respectively. Also, AC powder EL device fabricated in this study showed absolutely excellent characteristics as the lifetime was longer than products of other company.

• Journal of Sensor Science and Technology
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• v.7 no.2
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• pp.97-102
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• 1998

Organic thin film EL devices using PPV(poly (p-phenylenevinylene)) as emitter were fabricated on various conditions and structures, their electro-optical properties were estimated. Fabricated EL devices had structures of single layer(ITO(indium tin oxide)/PPV/Mg), double layer(ITO/PVK(poly(N-vinylcarbazole))/PPV/Mg and ITO/PPV/Polymer matrix + PBD/Mg) and three layer (ITO/PVK/PPV/PS(polystyrene)+PBD(butyl-2-(4-bipheny])-5-(4-tert-butylphenyl-1,3,4-oxadiazole))/Mg), their electro-optical characteristics were compared with each other. In structure of double layer (ITO/PPV /Polymer matrix + PBD/Mg), the used polymer-matrices were PMMA(poly(methyl methacrylate), PC(polycarbonate), PS and MCH(side chain liquid crystalline homopolymer). When PS as a hole transport layer was used, the luminance characteristics on concentration of PBD was obtained. In results, current-voltage-luminance curves of fabricated devices had characteristics of tunneling effect and the device showed a stable light emitting.

• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.315-320
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• 1999

Novel electroluminescent materials, polymer material, PU-BCN and low molar mass material, D-BCN with the same chromophores were designed and synthesized. A molecular structure of chromophore was composed of bisstyrylbenzene derivative with cyano groups as electron injection and transport and phenylamine groups as hole injection and transport. Device structures with PU-BCN and D-BCN as an emission layer were fa-bricated, which were a single-layer device(SL), Indium-tin oxide(ITO)/emission layer/MgAg, and two kinds of double-layer devices which were composed of ITO/emission layer/oxadiazole derivative/MgAg as a DL-E device and ITO/triphenylamine derivative/emission layer/MgAg as a DL-H device. The two emission materials, PU-BCN and D-BCN with the same emission-chromophore were evaluated as having excellent performance of charge injection and transport and revealed almost the same emission characteristics in high current density. EL emission maximum peaks of two material were detected at about 640 nm wavelength of red emission region.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1516-1518
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• 1997

Recently lots of study on EL have been performed by other researcher. Organic multilayer system of TPD/$Alq3$ and Rhodamine 101 perchrolate/Alq3/ was constructed on ITO and finally Al as cathodic electrode. The thickness of emitting layer was $150{\AA}$ and device was fabricated by changing amount of dopant. AFM image for each surface morphology and EL spectra using fluoromax-2 was investigated. Electrical and emission properties of EL device was dependent on deposition method and condition.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.12a
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• pp.114-118
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• 2006

We investigated the transient electroluminescence (EL) and modulation characteristics of red organic light-emitting diodes (OLEDs), which consist with 4-(dicyanomethylene)-2-i -propyl-6-(1,1,7,7-tetramethyljulolidyl-9-cnyl)-4H-pyran (DCJTI) and rubrene doped into tris(8-hydroxyquinoline)aluminum ($Alq_3$). The transient EL waveforms showed two components, the overshooting peak and constant component, indicating that the excess amount of accumulated charges simultaneously recombine at the onset moment. This overshooting effect reduced the rise time of transient EL and enhanced the optical output of OLEDs when the pulse voltage applied to the device. We demonstrated that the red OLEDs could be use for the high-speed switching application by driving at more than 100 MHz and transmitting the video signals utilized as the electro-optical conversion device

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1990.06a
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• pp.860-862
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• 1990

• Polymer Science and Technology
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• v.14 no.2
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• pp.242-246
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• 2003

• Transactions of Materials Processing
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• v.14 no.9 s.81
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• pp.731-740
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• 2005

• Electrical & Electronic Materials
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• v.12 no.6
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• pp.11-17
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• 1999

• Electrical & Electronic Materials
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• v.12 no.6
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• pp.35-40
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• 1999