• 한국세라믹학회지
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• 제49권4호
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• pp.375-379
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• 2012

Nitride phosphors are now attracting significant attention of material scientists and phosphor engineers, because they promise red-shifted photoluminescence spectra, small Stokes shift, high quantum efficiency and low thermal degradation. A number of interesting nitride phosphors have been developed and practiced for producing white light with LED chips. In this paper, the applications of nitride phosphors in highly reliable wLEDs will be overviewed.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1545-1546
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• 2007

Zinc gallate-based RGB phosphors and vertically aligned carbon nanotube emitters are prepared for flat field-emission lamp. The blend phosphors of blue $ZnGa_2O_4$, green $ZnGa_2O_4:Mn^{2+}$ and red $ZnGa_2O_4:Cr^{3+}$ are coated on the front glass, and the carbon nanotubes are chemically bonded on the rear ITO glass as a cathode.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1132-1133
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• 2015

In this paper, we are presents production and operation characteristics for inorganic EL phosphors device using screen printed. The EL device is composed as ITO PET / EL phosphors dielectric $(2{\times}2cm^2)/TiO^2$ paste/Ag electrode. At 100Vac 400Hz, the luminescence of inorganic EL phosphors were $60.33cd/m^2$ of red phosphor, $42.12cd/m^2$ of green phosphor and $58.45cd/m^2$ of blue phosphor. The output current was 12.57 mA, 17.11 mA and 11.98 mA, respectively. The inorganic EL phosphors of EL device are increasing efficiency EL device.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.788-791
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• 2002

The phosphors of high luminous efficiency for PDP application must have high purity, single phase, and dense surface. In this work, the polymeric reaction was applied to preparation of spherical phosphor by aerosol pyrolysis in order to enhance mechanical and optical characteristics. The red phosphor of (Y,Gd)$BO_3$:Eu was prepared from polymeric precursor, in which citric acid and ethylene glycol were used as ion carriers, i.e monomers. For enhancing the luminescence intensity and mechanical characteristics. optimum synthesizing condition were investigated through concentration of monomers, synthetic temperature. doped activator concentrations, and annealing process. The phosphors synthesized with monomers showed quite different morphology from those without monomers. It was observed that polymeric precursor made an effect on particle formation mechanism and status of particles surface. The resultant spherical phosphors show the comparable luminescent properties to the commercial product (product by Nichia co.). Also, they were observed to have the rigid surface.

• 한국전기전자재료학회논문지
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• 제21권11호
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• pp.1019-1023
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• 2008

Photoluminescence properties of $SrTiO_3$:Sm red phosphors synthesized by solid state reaction method were studied under 254 nm excitation. Emission bands at 576 nm and 616 nm in heavily $Sm^{3+}$ ion doped $SrTiO_3$:Sm phosphors were observed, which were attributed to $^4G_{5/2}\rightarrow{^6}H_{5/2}$ and $^4G_{5/2}\rightarrow{^6}H_{7/2}$ transition of $Sm^{3+}$, respectively. The $Sm^{3+}$ ion concentration exhibiting the maximum emission intensity in the $SrTiO_3$:Sm was 30 mol%. The luminescence caused by $Sm^{3+}$ in the $SrTiO_3$:Sm phosphors was interpreted by the energy transfer between $Sm^{3+}$ ions.

• 한국전기전자재료학회논문지
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• 제21권9호
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• pp.825-828
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• 2008

$Sr_xBa_{(1-x)}TiO_3$ red phosphors doped with Pr(0.13 mol%) and Al(O.23 mol%) were synthesized by solid state reaction method. Orthorhombic perovskite structure with increasing value of x in $Sr_xBa_{(1-x)}TiO_3$:Pr,Al phosphors changed to cubic perovskite structure. Emission bands at 615 nm and 492 nm in $Sr_{0.25}Ba_{0.75}TiO_3$:Pr,Al and $BaTiO_3$:Pr,Al phosphors were observed at room temperature. The main cause of green luminescence at 492 nm was explained by the change of the 4f5d band.

• 반도체디스플레이기술학회지
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• 제19권2호
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• pp.22-25
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• 2020

Deep red EuSi₂O₂N₂ phosphors were synthesized under various sintering gas pressures (1 atm, 2 atm, and 3 atm). They were in good agreement with the standard EuSi₂O₂N₂ ICSD card # 41-6046 (a monoclinic crystal system with space group of P2₁/a). Their photoluminescence intensities were significantly increased with increasing the gas pressures. They showed a broad band emission peaking at 680 nm due to 4f⁶5d¹ - 4f⁷ of Eu²⁺ ion, which can be efficiently excited in the visible range up to 550 nm. The best one at 3 atm was applied for red LED based on blue chip, which showed the strong deep red emission.

• 한국표면공학회지
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• 제48권5호
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• pp.211-217
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• 2015

To fabricate white LED having a high color rendering index value, red color phosphor mixed with the green color phosphor together in the blue chip, namely the blue chips with RG phosphors packaging is most favorable for high power white LEDs. In our previous papers, we reported on successful syntheses of $Sr_{2-}$ $Si_5N_8:Eu^{2+}$ and $CaAlSiN_3$ phosphors for red phosphor. In this work, for high power green phosphor, greenemitting ternary nitride $Ba_3Si_6O_{12}N_2:Eu^{2+}$ phosphor was synthesized in a high frequency induction furnace under $N_2$ gas atmosphere at temperatures up to $1400^{\circ}C$ using $EuF_3$ as a raw material for $Eu^{2+}$ dopant. The effects of molar ratio of component and experimental conditions on luminescence property of prepared phosphors have been investigated. The structure and luminescence properties of prepared $Ba_3Si_6O_{12}N_2:Eu^{2+}$ phosphors were investigated by XRD and photoluminescence spectroscopy. The excitation spectra of $Ba_3Si_6O_{12}N_2:Eu^{2+}$ phosphors indicated broad excitation wavelength range of 250 - 500 nm, namely from UV to blue region with distinct enhanced emission spectrum peaking at ${\approx}530nm$.

• 대한화학회지
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• 제45권6호
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• pp.577-588
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• 2001

조합화학 기법을 적용하여 $YRO_4$ (R=As, Nb, P, V)계 모체에 Eu을 활성하여 적색형광체를 합성하였다. 합성된 형광체는 UV PL,VUV PL, 및 색좌표 분석을 하였고, 254nm 및 147nm 여기하에서의 발광세기 및 색좌표 사면체 라이브러리를 완성하였다. Eu이 0.1 mol 도핑된 적색 형광체는 254nm로 여기 시켰을 때 $YRO_4$를 중심으로 다른 중심으로 다른 성분이 미량 첨가되었을 때 가장 좋은 발광 세기를 나타내었으나. 147nm에서는 $YRO_4$를 중심으로 좋은 발광 세기가 나타났다. 합성된 형광체 중 $Y_{0.9}$(A$S_{0.06}$N$B_{0.06}$$P_{0.83}$$V_{0.06}$) $O_4$: $Eu_{0.1}$의 조성으로 1200$^{\circ}C$에서 소성하였을 때 상용 형광체와 대등한 발광세기가 색순도가 우수하였다.

• 한국결정성장학회지
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• 제17권5호
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• pp.204-209
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• 2007

형광체-변환 3파장 백색 발광 다이오드(LED)의 응용을 위하여 일련의 $CaS_{1-x}Se_x:Eu$ 형광체를 합성하였다. $CaS_{1-x}Se_x:Eu$의 구조와 발광 특성을 조사하였다. $CaS_{1-x}Se_x:Eu$ 형광체는 청색 발광 다이오드의 발광 파장인 455nm에서 강한 흡수가 있다. $Eu^{2+}$의 $4f^65d^1(T_{2g}){\rightarrow}4f^7(^8S_{7/2})$ 전이 때문에 CaS:Eu는 651nm에서 적색 발광 봉우리를 가지고 있다. $CaS_{1-x}Se_x:Eu$의 발광 봉우리는 Se이 증가함에 따라서 651nm에서 598nm으로 이동이 된다. $CaS_{1-x}Se_x:Eu$ 형광체는 청색 LED로 여기하면 가변 파장의 적색 발광을 하는 형광체로 사용될 수 있다. $SrGa_2S_4:Eu$와 $CaS_{0.50}Se_{0.50}:Eu$ 형광체를 청색 발광 다이오드에 도포하여 백색 발광 다이오드를 제작하였다.