• 한국결정성장학회지
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• 제10권6호
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• pp.400-406
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• 2000

전구체인 (Y,Gd,Eu)(OH)$CO_3$.$H_2O$를 $900^{\circ}C$에서 열처리하여 얻은 분말을 플라즈마 디스플레이용 적색 형광체 $(Y,Gd)_2O_3$: Eu를 제조하기 위하여 이용하였다. 크기가 대략 1$\mu\textrm{m}$의 구형 형광체 $(Y,Gd)_2O_3$: Eu는 위의 분말에 소량의 융제를 첨가하여 $1350^{\circ}C$에서 2시간 소성하면 얻을 수 있다. 제조된 형광체의 발광 스펙트럼은 여기원이 254 nm와 147 nm인 파장에서 측정하였으며 최적인 활성제의 농도는 254 nm 하에서는 15 몰 %, 147 nm에서는 10 몰 %로 결정되었다. 또한 발광세기를 비교한 결과 BaCO$_3$, $AlF_3$및 $Li_3PO_4$중 $BaCO_3$가 가장 우수한 것으로 나타났다. 최적화된 형광체 $(Y,Gd)_2O_3$: Eu의 상대 휘도 및 색좌표는 상용품인 $Y_2O_3$: Eu 보다 개선되는 것으로 평가되고 있다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.918-920
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• 2006

Metal sulfide powders such as MnS, $MoS_2$ and FeS are simply used to the machinery processing improvement agent and solid lubricant in powder metallurgy industrial. And then, metal sulfide powders have received relatively little attention from powder metallurgy. Recently, the portable machine is one of the important interfaces between human or human and electronic machine. With the increase of the intelligent activity, the social and industrial demands for information display device and power source are increasing. The transition metal sulfide materials (FeS, ZnS) have received considerable attention due to the large variety of its electric, optical and magnetic properties. Among the metal sulfide, $FeS_2$ is appealing superior material for applications in $Li-2^{nd}$ battery because of high capacity. ZnS is also a famous phosphor material with various luminescence properties, such as photoluminescence (PL) and electroluminescence (EL). So generally used in the fields of display, sensors and laser. Metal sulfide materials, therefore, are provided for most widely application in all industries. In recent years, material researchers have become increasingly interested in studying with synthesis of metal sulfide.

• 한국결정성장학회지
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• 제30권4호
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• pp.131-135
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• 2020

단결정상을 가지는 CaZrO₃ : Eu³⁺ 형광체를 스컬용융법으로 합성하였다. 합성된 형광체의 결정구조, 형태 및 광학적 특성은 XRD, SEM, UV 형광반응 및 PL을 분석하였다. 출발 원료는 CaO : ZrO₂ : Eu₂O₃를 0.962 : 1.013 : 0.025 mol%로 하여 냉각도가니에 충진하였다. 냉각도가니는 내부 직경 120 mm, 높이 150 mm이며, 혼합된 파우더 3 kg은 3.4 MHz의 출력 주파수로 1시간 이내에 완전히 용융되어 2시간 동안 유지시킨 후 자연냉각 시켰다. XRD 측정에서는 다른 결정상은 측정되지 않았으며 페로브스카이트 구조의 정방정계로 분석되었다. 합성된 형광체는 UV 광에 의해 여기 될 수 있고 방출 스펙트럼 결과는 615 nm에서 자기 쌍극자 전이 ⁵D₀→⁷F₂로 인해 CaZrO₃ : Eu³⁺의 밝은 적색 발광이 우세하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.27-32
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• 2006

The present status and prospects for further development of thin-film electroluminescent (TFEL) devices using oxide phosphors are described. High-luminance oxide TFEL devices have been recently developed using a new combinatorial deposition technique featuring rf magnetron sputtering with a subdivided powder target. In addition, new flexible oxide TFEL devices have been fabricated on an oxide ceramic sheet and operated stably in air above $200^{\circ}C$.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2005년도 춘계학술발표대회 및 제8회 신소재 심포지엄 논문개요집
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• pp.147-147
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• 2005

• 한국분말재료학회지
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• 제19권6호
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• pp.442-445
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• 2012

The quantum dots (QD) have unique electrical and optical properties due to quantum dot confinement effect. The optical properties of QDs are decided by various synthesis conditions. In a prior QDs study, a study on the QDs size with synthesis condition such as synthesis time and temperature is being extensively researched. However, the research on QDs size with composition ratio has hitherto received scant attention. In order to evaluate the ratio dependence of CdSe crystal, synthesis ratio of Se precursor is changed from 16.7 mol%Se to 44 mol%Se. As the increasing Se ratio, the band gap was increased. This is caused by red shift of emission. We confirmed optical property of CdSe QDs with composition ratio.

• 대한방사선기술학회지:방사선기술과학
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• 제23권1호
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• pp.97-101
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• 2000

In this study, the highly sensitive $CaSO_4:Tm$-PTFE TLDs has been fabricated for the purpose of measurement of high energy electron. $CaSO_4:Tm$ phosphor powder was mixed with polytetrafluoroethylene(PTFE) powder and moulded in a disk type(diameter 8.5 mm. thickness $90\;mg/cm^2$) by cold pressing. The absorbed dose distribution and ranges for high energy electron were measured by using the $CaSO_4:Tm$-PTFE TLDs. The ranges determined were $R_{100}=14.5mm$, $R_{50}=24.1mm$ and $R_P=31.8mm$, respectively and the beam flatness, the variation of relative dose in 80% of the field size, was 4.5%. The fabricated $CaSO_4:Tm$-PTFE TLDs nay be utilized in radiation dosimetry for personal, absorbed dose and environmental monitoring.

• 전기학회논문지
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• 제64권11호
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• pp.1587-1591
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• 2015

For a higher definition discharge cell, the method of high speed addressing is necessary. In order to modify the surface charges, the liquefied $TiO_2$ or MgO powder is added on MgO layer in front glass and on the phosphor in rear glass in micro barrier discharge. Both the electro-optical properties and the discharge time lag characteristics are measured from 4 inch. test panel, such as the discharge voltage, current, luminance, luminous efficacy and discharge time lag. As the results, the statistic time lag is improved by about 40 %.

• 반도체디스플레이기술학회지
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• 제20권2호
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• pp.73-76
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• 2021

This thesis described the optical and electrical properties of the alternating current powder electroluminescent device based on Ag nanowire as a transparent electrode. The Ag nanowire electrode showed the morphology of 20 nm in diameter and 15 ㎛ in length. The transparent electroluminescent devices that were fabricated using the nanomilled ZnS : Cu, Mn phosphor by bar-coating process showed the transmittance of 67%. In order to improve the luminous efficiency, it is necessary to apply the transparent dielectric layer and increase the amount of the nanophosphor while maintaining the transmittance.

• 한국재료학회지
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• 제8권7호
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• pp.601-606
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• 1998

고상반응법으로 $SrTiO_3$ : AI, Pr 적색 형광체를 합성하였다. PL 스펙트럼과 CL 스펙트럼의 발광 강도를 소결 온도와 소결 시간등의 형광체의 제조 변수에 대하여 최적화 하였다. 열처리한 분말은 XRD 분석 결과 페로브스카이트구조를 보였고, PSD 분석결과 평균입자크기는 약 3~5$\mu\textrm{m}$이었다. 또한 분말의 주사 전자 현미경 사진에 의한면 구형을 갖는잘 결정화된 입자들이 관찰되었다. 특히, 본 연구에서 합성된 분말의 특성은 상용화된 $Y_2O_3: Eu 형광체 보다 저전압에서의 CL 특성이 더 우수하였으며, 이 형광체는 저전압에서 구동하는 FED에 응용할 가능성이 높을 것으로 생각된다.