• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.268-269
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• 2006

The estimation of applicability $SrTiO_3:Pr^{3+}$, Al to a class low-voltage flat-panel displays based on field emission effect, which have average value anode voltage $U_a=300V$ and current density $j=100\;mA/sm^2$ at duty 240, has given positive result. In the same time observably for the most effective sample in similar conditions of excitation high brightness - more than $500\;Kd/m^2$ and linear brightness dependences from current density and voltage allows to decrease greatly the power which consumed by the device.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.885-886
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• 2003

A bilayer is used as an anode electrode for organic electroluminescent devices. The bilayer consist of an ultrathjn ZnO layer adjacent to an hole-transporting layer and an Indium tin oxide(ITO) outerlayer. We tried to bring low the barrier between the devices as deposited ZnO films on ITO substrates. We fabricated the organic EL structure consisted of Al as cathode, $Al_{2}O_{3}$ as electro transport layer, Alq3 as luminously layer, triphenyl diamine(TPD) as hole transport layer and ZnO(l nm )/ITO(l50 nm) as anode. The result of this experiment was not good compared with the case of using ITO, Nevertheless, at this structure we obtained the lowest turn-on voltage as the value of 19 V and the good brightness (6200 $cd/m^{2}$) of the emission light from the devices. Then the quantum efficiency was to be 1.0%.

• Proceedings of the Korea Crystallographic Association Conference
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• 2003.05a
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• pp.6-6
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• 2003

Highly crystalline 5H-polytypic form of sp3-bonded boron nitride (BN) was grown by pulsed-laser-vaporization of BN, where synchronous reactive-plasma packets assisted the crystal growth in the vapor phase. The structure of the product crystallites (˙5 micrometers) was confirmed by using transmission electron diffraction and electron energy loss spectroscopy. This material proved to have a sharp and dominant band at 225 nm by cathode luminescence at room temperatures and corresponding monochromatic images revealed that they uniformly emitted the ultraviolet light. Considering that cubic BN has already been doped as p- and n- type semiconductors, this material may be applied to the light-emitting devices working at almost the deepest limit of the UV region that is functional without vacuum.

• Proceedings of the KIEE Conference
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• 2008.11b
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• pp.89-91
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• 2008

Organic EL has been expected to adopt to a new styles of technology that make flat display after Tang & Vanslyke made good electric luminescence device in late 1980s. Their studies based on multi layer structure that consists of emitting layer and carrier transporting layer using proper organic material. But oxidization of organic layer by ITO, energy walls in both pole interface, contaminations of ITO surface, importance of protecting membrane, diffusive dimming of light to cathode organic layer, these causes of degradations are common facts of a macromolecule and micro molecule. We think these degradation caused by the impact of heat and electro-chemical factor, bulk effect and interface phenomenon, and raise a question.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.57-57
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• 2010

Self assembled $Zn_{x-1}Cd_xS$ nanowires, synthesized on a Indium tin oxide coated glass substrate with low composition of Cd as x=0.09, were fabricated non-precursor via a co-evaporation method using of solid sources of CdS and ZnS. We studies that ZnCdS nanowires are dislocation-free and the single crystalline hexagonal wurtzite structure showed by transmission electron microscopy and selected area electron diffraction pattern. Cathode luminescence spectra showed an near band edge peak at 383nm originated from nanowires at 80K and 300K. Core level spectra of the Cd 3d, Zn 2p and S 2p in the ZnCdS nanorods were obtained by x-ray photoelectron spectroscopy. Prepared ZnCdS nanorods showed different shape with increase of substrate temperature at the growth.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.555-558
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• 2004

The efficiency of electron injection from the cathode is strongly dependent on the thickness of the LiF buffer-layer. We used LiF to electron Injection layer. We compared characteristics of organic light emitting device changing LiF thin film thickness from 1.0 m to 10.0 nm. Experiment result, we found that LiF thickness has the optimized electrical characteristics in 3.0 m. In this paper, we did research about electrical characteristics of organic light emitting device by LiF thickness change using method numerical analysis method. We proved adequate experimental results that compare results of numerical analysis, and come out through an experiment results is validity.

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.284-285
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• 2003

Significant research interest in the growth and characterization of $Y_2$O$_3$：Eu$^{3+}$ thin films has been shown over the last few years because of the promise for applications of display devices. Although an Eu-doped oxysulfide (Eu： $Y_2$O$_2$S) which has an efficiency of 13％ has been used for a traditional cathode ray tube (CRT) red phosphor, the sulfide system is known to degrade rapidly under the high current densities needed for field-emission display (FED) technology. (omitted)d)

• Journal of the Korean Chemical Society
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• v.48 no.4
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• pp.371-378
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• 2004

The $SrGa_2S_4:Eu^{2+}$ green emitting phosphor has been studied as a luminous device for CRT (Cathode Ray Tube) or FED (Field Emission Display) and EL (Electroluminescence). This phosphor, also, is under noticed for LED (Lighting Emitting Diode) phosphor, which makes use of excitation characteristics of long wavelength region. The $SrGa_2S_4:Eu^{2+}$ phosphor was prepared generally conventional synthesis method using flux. However, this method needs high heat-treated temperature, long reaction time, complex process and harmful $H_2S$or $CS_2$ gas. In this works, therefore, we have synthesized $SrGa_2S_4:Eu^{2+}$ using SrS, $Ga_2S_3$, and EuS as starting materials, and the mixture gas of 5% H2/95% N2 was used to avoid the $H_2S$or $CS_2$. We investigated the luminescence characteristic of $SrGa_2S_4:Eu^{2+}$ phosphor prepared in various synthesis conditions, performed post-treatment and sieving process for application to LED.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.309-310
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• 2005

In the fabrication of high performance red organic light emitting diode, 2-TNA TA [4,4',4" -tris (2-naphthylphenyl- phenylamino)-triphenylamine] as hole injection material and N PH [N,N'-bis (1-naphthyl) -N,N' -diphenyl-1, 1'-biphenyl-4,4'- diamine] as hole transport material were deposited on the ITO (indium tin oxide)/glass substrate by vacuum evaporation, And then, red color emission layer was deposited using Alq3 as a host material and Rubrene (5,6,11,12- tetraphenylnaphthacene) and GDI 4234 as dopants. Finally, small molecular weight OLED with the structure of ITO/2-TNATA/ NPB/Alq3+Rubrene+GDI4234/Alq3/LiF/Al was obtained by in-situ deposition of Alq3, LiF and Al as electron transport material, electron injection material and cathode. respectively. Green OLED fabricated in our experiments showed the color coordinate of CIE(0.65,0.35) and the maximum luminescence efficiency of 2.1 lm/W at 7 V with the peak emission wavelength of 632 nm.

• Journal of Korea Society of Industrial Information Systems
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• v.10 no.2
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• pp.76-81
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• 2005

This research approached electrical characteristics of organic light emitting diodes getting into the spotlight by next generation display device. Basic mechanism of OLED's emitting is known as that electron by cathode of lower work function and hole by anode of higher work function are driven and recombine exciton-state being flowed in emitting material layer passing carrier transport layer In order to make many electron-hole pairs, we must manufacture device in multi-layer structure. There are Carrier Injection Layer(CIL), Carrier Transport Layer(CTL) and Emitting Material Layer(EML) in multi-layer structure. It is important that regulate thickness of layer for high luminescence efficiency and set mobility of hole and electron.