• Korean Journal of Optics and Photonics
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• v.26 no.5
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• pp.265-268
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• 2015

An inorganic electroluminescence device based on a green ZnS:(Cu,Al) phosphor was fabricated by a screen printing method. Graphene was added to the phosphor layer to increase the electroluminescence intensity. As the graphene concentration increased, the photoluminescence intensity decreased; on the other hand, the electroluminescence intensity increased, up to 0.6 wt%.

• Journal of the Semiconductor & Display Technology
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• v.21 no.2
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• pp.15-18
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• 2022

The ultraviolet-C emitting praseodymium doped yttrium phosphate (YPO₄:Pr³⁺) powder was synthesized by conventional solid-state reaction. The electroluminescence device was fabricated by simple screen-printing method using the synthesized YPO₄:Pr³⁺ powder, especially, polyvinylidene fluoride as an insulating layer was applied on the printed YPO₄:Pr³⁺ powder for stable performance of the electroluminescence. The electroluminescence properties were investigated under alternating current power system of 400 Hz. The device starts to emit at 350 V, which showed the ultraviolet-C emission peaking at the 233, 245, 264, 273 nm attributed to electronic transition of the Pr³⁺ ions. The electroluminescence intensity was increased as increasing the operating voltage and the device revealed stable performance up to 600 V due to the polyvinylidene fluoride serve as a protective layer.

• Journal of the Semiconductor & Display Technology
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• v.22 no.1
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• pp.83-87
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• 2023

Y₂SiO₅ Powder based on silicon and yttrium is well known as powder phosphors due to their excellent sustainability and efficiency. A new electroluminescence device was fabricated with Y₂SiO₅:Eu³⁺ powder phosphors though a simple screen printing method. The powder-dispersed electroluminescence device consisted of the Y₂SiO₅:Eu³⁺ powder-dispersed phosphor layer and BaTiO₃-dispersed dielectric layer. The annealing temperature of the phosphor for the best powder electroluminescence performance was optimized to high temperature in ambient atmosphere though a solid-state reaction. The Eu³⁺ concentration for the best device performance was also investigated and furthermore, the thermal dependence of the electroluminescence intensity was investigated at the operating voltage at 100℃, which is the Curie temperature of the BaTiO₃ layer. And the intensity was exponentially increased with voltage and increased linearly with frequency.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.112-116
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• 2001

Organic Electroluminescence device, which have the single-layer structure of ITO(indium-tin-oxide)/MEH-PPV (Poly[2-(2'-ethylhexyloxy )-5-methoxy-1,4-pheny lenevinylene])/Al(aluminium) and ITO/MEH-PPV/$Alq_3$(tris-8-hydroxyquinolinato aluminium)/Al were fabricated and electrical properties were investigated. Experimental results, in single-layer structure, shown that turn on voltage is about 12 V, and current density increases as a function of increasing temperature. It was explained by thermionic emission. In double-layer structure, thickness $200\AA$ of $Alq_3$ is shown electrical properties that turn on voltage is about 11 V, and current density decreases as a function of increasing temperature.ࠀȀ 耀Ѐ€

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.112-116
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• 2001

Organic Electroluminescence device, which have the single-layer structure of ITO(indium-tin-oxide)/MEH-PPV (Poly [2-(2'-ethylhexyloxy)-5-methoxy-1, 4-phenylenevinylene])/Al(aluminium) and ITO/MEH-PPV/Alq$_3$(tris-8-hydroxyquinolinato aluminium)/Al were fabricated and electrical properties were investigated. Experimental results, in single-layer structure, shown that alum on voltage is about 12 V, and current density increases as a function of increasing temperature. It was explained by thermionic emission. In double-layer structure, thickness 200 $\AA$ of Alq$_3$ is shown electrical properties that turn on voltage is about 11V, and current density decreases as a function of increasing temperature.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.261-264
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• 2000

Organic light emitting diodes(OLEDs) have been expected to find an application as a new type of display since C. W. Tang and VanSlyke first reported on high performance OLEDs. This paper has been stuied a green organic EL device using dye doped emitting layer such as C6(Coumarin 6). In the Alq-based e]ectroluminescence diodes, we applied highly fluorescent molecular(Coumarin 6) and obtained enhancement in the electroluminescence efficiency.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.439-442
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• 1998

In this paper, organic thin film LED(light emitting diode) having ITO glass/Alq$_3$/Al structure using an Alq$_3$ was fabricated by the vacuum evaporation and the absorbance, wave length, I-V characteristics were investigated, Electroluminescence of green and wavelength of 510[nm] were observed in this device. We observed absorbance form 320[nm] to 430[nm] and knew unstability of Alq$_3$ material as light emitting device.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.528-530
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• 2002

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.807-811
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• 2002

We present a hypothetical quantum scattering model to propose a novel electroluminescence device. Adoping with features of solid state semiconductor LED and exciplex laser, the cathode (electrol incoming potential) and anode(electron outgoing potential) are made to correspond to two 1-dimensional resonance supporting potentials, and the light emitting part to an interaction potential in the intermediate region. When an external voltage is applied, the electron flows into the cathode having small work function. Subsequently in flows via LUMO of the " electron incoming potential" loses kinetic energy emitting a photon, then continues to flow via LUMO of the "electron outgoing potential" unlike the conventional LUMO to HOMO transitions occurring in solid state semiconductor LED. In this model, the photon frequency can be controlled by adijusting the applied voltage. The model hopefully could be realized as partially conjugated hydrocarbon chains.

• ETRI Journal
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• v.18 no.3
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• pp.181-193
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• 1996

A blue light emitting device has been successfully fabricated using a polymer with regulated conjugation length containing trimethylsilyl substituted phenylenevinylene units. Electroluminescence from the device has an emission maximum at 470 nm. The device shows typical diode characteristics with operating voltage of 20 V and the light becomes visible at a current density of less than $0.5;mA/cm^2$. The electroluminescence spectrum is virtually identical with the photoluminescence spectrum, indicating that the radiation mechanisms are the same for both. A light emitting device using the blend of a large band gap polymer and a small band gap polymer was also fabricated. Light emission from the small band gap polymer shows much improved quantum efficiency, but there is no light emission from the large band gap polymer. Quantum efficiency of the blend increases up to about two orders of magnitude greater than that of the small band gap polymer with increasing proportion of the large band gap polymer. The improvement in quantum efficiency is interpreted in terms of exciton transfer and the hole blocking behaviour of the large band gap polymer. Finally, we have fabricated a patterned flexible light emitting device using the high quantum efficiency polymer blend system.