• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.635-638
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• 2002

In $ABCO_4$ and $ABC_3O_7$ (A=Ca, Sr; B=Y, Rare earth; C=Al, Ga), random distribution of static crystalline fields in activator sites results in inhomogeneous broadening of spectral lines of luminescent materials. In this study, we investigated luminescent properties of above-mentioned materials by excitation and emission spectra. In result, both $ABCO_4$:Tb and $ABC_3O_7$:Tb phosphors emit the green light. $ABC_3O_7$:Tb phosphors absorbed shorter wavelength energy than $ABCO_4$ phosphors so that the emission efficiencies of $ABC_3O_7$:Tb phosphors were higher than those of $ABCO_4$:Tb phosphors under vacuum UV.

• Journal of the Korean Ceramic Society
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• v.43 no.9 s.292
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• pp.569-574
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• 2006

Transparent glass-ceramics containing fresnoite crystals have been prepared by controlled heat treatment in $K_2O-BaO-TiO_2-SiO_2$ and their nonlinear optical and luminescent properties were investigated using Maker fringe method and Spectrofluorometer. The second harmonic generation was observed in all samples and the values decreased with increasing $K_2O$ content. The luminescence of blue light at ${\sim}482nm$ could be observed and it was shown that the luminescent property was controlled by the $K_2O$ content.

• Korean Journal of Materials Research
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• v.12 no.1
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• pp.21-26
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• 2002

In order to search new phosphors for plasma display panel(PDP), phosphate hosts which has a host excitation band at around 150nm were prepared and their luminescent properties were investigated. In the preparation of $YPO_4: Eu\; and\; (Y,Gd)PO_4: Eu$ phosphors, the effect of oxide and oxalate starting materials on prepared phosphors were compared in terms of relative emission intensities and particle characteristics. The results showed that oxalate starting materials gave better performance in emission intensities and smaller size and more round shape phosphors which would be more applicable for high resolution display. Additionally, Gd, V, Nb and Ta ions were doped to $YPO_4:Eu$ and the luminescent properties of the resulant solid solutions were investigated to find efficient sensitizer. Among these ions, Gd, V and Nb ions increased the emission intensities of parent phosphor to around 10%. While Nb ion gave the best result in emission intensities, CIE color coordinate were improved by doping V ion into $YPO_4:Eu$ phosphor to give x=0.6523, y=0.3406 compared to commercial sample.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1623-1626
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• 2005

The thiogallate phosphors which are well known for a long time as phosphor materials for CRT or EL device were reported. Those have high luminescent properties at long-wavelength region. Among those phosphors, the samples with divalent europium doped CaGa2S4 were prepared by a simple process under the reduction atmosphere $(5%\;H_2/\;95%\;N_2)$ without toxic gas such as H2S or CS2. The prepared phosphor shows a higher luminescent efficiency (about 120%) than that of $YAG:Ce^{3+}$ phosphor. Consequently, this phosphor is possible to be applicable to white LED lamp because of the high luminescent efficiency.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.2
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• pp.158-162
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• 2009

$Zn_2SiO_4$:Mn green phosphors doped with Ga for PDP were synthesized by solid state reaction method. Photoluminescence measurements showed a new emission peak at around 600 nm for $Zn_2SiO_4$:Mn phosphors doped with Ga. Also, the luminescent color with doping $Ga^{3+}$ in the $Zn_2SiO_4$:Mn phosphors changed to green from yellowish green. Consequently, the new peak and charge of the luminescent color in the $Zn_2SiO_4$:Mn, Ga phosphors were attributed to $^2E{\rightarrow}^6A_2$ transition of $Mn^{4+}$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.6
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• pp.582-587
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• 2023

The effects of the annealing temperature on the structural, morphological, and luminescent properties of SrWO₄:Sm³⁺ thin films grown on quartz substrates by radio-frequency magnetron sputtering were investigated. The thin films were annealed at various annealing temperatures for 20 min in a rapid thermal annealer after growing the thin films. The experimental results showed that the annealing temperature has a significant effect on the properties of the SrWO₄:Sm³⁺ thin films. The crystal structure of the as-grown SrWO₄:Sm³⁺ thin films was transformed from amorphous to crystalline after annealing at 800℃. The preferred orientation along (112) plane and a significant increase in average grain size by 820 nm were observed with increasing the annealing temperature. The average optical transmittance in the wavelength range of 500~1,100 nm was decreased from 72.0% at 800℃ to 44.2% at an annealing temperature of 1,000℃, where the highest value in the photoluminescence intensity was obtained. In addition to the red-shift of absorption edge, a higher annealing temperature caused the optical band gap energy of the SrWO₄:Sm³⁺ thin films to fall rapidly. These results suggest that the structural, morphological, and luminescent properties of SrWO₄:Sm³⁺ thin films can be controlled by varying annealing temperature.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.9
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• pp.846-850
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• 2005

[ $SrTiO_3$ ]:Al, Pr red phosphors for FED were synthesized by solid state reaction method. The dependence of their luminescent properties on Sr and Al concentration was investigated. The $SrTiO_3$: Al, Pr phosphors showed the characteristic X-ray diffraction patterns of the perovskite structure. Photoluminescence intensity and lattice constant in $SrTiO_3$: Al, Pr phosphors changed in quite a similar manner with Sr concentration. Photoluminescence intensity increased with increasing lattice constant, and the decrease of photoluminescence intensity and lattice constant occurred in the vicinity of 1 mol Sr concentration.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.784-787
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• 2008

Nanoscale $YVO_4:Eu^{3+}$ phosphor has been synthesized by a mild hydrothermal reaction at various experimental conditions. The particle and luminescent properties of nanophosphors were characterized with X-ray diffraction, electron microscopy and photoluminescence. It has been found that pH value play a key factor both controlling particle size and luminous efficiency.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.531-531
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• 2012

So many groups have been researching the green quantum dots such as InP, InP/ZnS for overcoming the semiconductor nanoparticles composed with heavy metals like as Cd and Pb so on. In spite of much effort to keep up CdSe quantum dots, it does not reach the good properties compared with CdSe/ZnS quantum dots. This quantum dot has improved its properties through the generation of core/shell CdSe/ZnS structure or core/multi-shell structures like as CdSe/CdS/ZnS and CdSe/CdS/ CdZnS/ZnS. In this research, we try to synthesize the InP multi-shell structure by the successiveion layer absorption reaction (SILAR) in the one pot. The synthesized multi-shell structure has improved quantum yield and photo-stability. To generate white light, highly luminescent InP multi-shell quantum dots were mixed with yellow phosphor and integrated on the blue LED chip. This InP multi-shell improved red region of the LEDs and generated high CRI.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.05a
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• pp.80-80
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• 1998