• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.37-38
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• 2000

The ZnS:Tb thin-film electroluminescent devices were grown by atomic layer deposition with utilizing single-layer aluminum oxide and/or multilayered tantalum aluminum oxide, $Ta_xAl_yO$, as upper and lower insulating layers. These devices were investigated in terms of the luminescent and electrical characteristics. From this analysis, the devices using the $Ta_xAl_yO$ instead of $Al_2O_3$ were observed to have a lower threshold voltage for emission due to the higher relative dielectric constant of $Ta_xAl_yO$ insulators than that of the $Al_2O_3$ device. And there was a large amount of dynamic space charge generation in the phosphor of the device with the $Ta_xAl_yO$ insulators seemingly due to electron multiplication such as trap ionization.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.149-150
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• 2000

Lead-doped calcium sulfide(CaS:Pb) thin film electroluminescent devices were deposited using atomic layer deposition(ALD). CaS:Pb is a very promising blue phosphor showing very high luminance and the color coordinate close to the blue of cathode ray tube. The luminance, $L_{25}$, of CaS:Pb(1.6 mol.%) EL device was higher than 80 $cd/cm^2$ at a driving frequency of 60Hz. The color coordinates of blue EL emission of CaS:Pb deposited by ALD are consistent with the Pb concentration ranging from approximately 0.5 to 3 mol.%.

• 센서학회지
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• 제6권1호
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• pp.63-71
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• 1997

ZnS:Mn/$ZnS:TbF_{3}$적층구조의 TFEL(thin-film eletroluminescent)소자를 제작하였으며, 이때 절연층으로 (Pb,La)$TiO_{3}$(이하PLT)와 $SiO_{2}$박막을 이용하였다. TFEL소자는 $78V_{rms}$의 문턱전압과 $100V_{rms}$의 인가전압에서 $400{\mu}W/cm^{2}$의 휘도를 나타내었다. TFEL소자의 발광스펙트럼은 450nm에서 630nm사이의 파장대를 보이고 있다. 제작된 TFEL소자는 컬러필터를 병용함으로서, 적 녹 청의 색상을 구현하는 TFEL소자로 활용할 수 있다.

• 센서학회지
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• 제11권2호
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• pp.118-123
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• 2002

$ZnGa_2O_4$ 형광체 박막을 기판 온도를 $550^{\circ}C$에 고정시키고 산소 분압을 100, 200, 300 mTorr로 변화시키며 $Al_2O_3$(0001) 기판 위에 펄스 레이저 증착법을 이용하여 증착하였다. 다른 산소 분압에서 성장한 박막들의 미세 결정구조와 형광특성을 조사하였으며, 산소분압이 증가할수록 박막의 결정성이 변화하였으며 박막의 조성비가 다름을 형광특성을 통하여 알 수 있었다. 발광 스펙트럼은 460 nm에서 최고 피크값 을 나타내었으며, 300 nm에서 600 nm까지 갖는 넓은 밴드의 형광 특성을 나타내었다. 최적의 조건에서 성장된 박막의 형광 밝기를 고려해볼 때 $Al_2O_3$(0001) 기관이 우수한 $ZnGa_2O_4$ 형광체 박막을 성장시킬 수 있는 기판들 중 하나임을 확인하였다.

• Transactions on Electrical and Electronic Materials
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• 제5권4호
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• pp.133-137
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• 2004

The development of digital x-ray detector has been extensively progressed for the application of various medical modalities. In this study, we introduce a new hybrid-type x-ray detector to improve problems of a conventional direct or indirect digital x-ray image technology, which composed of multi-layer structure using a CaWO$_4$ phosphor and amorphous selenium (a-Se) photoconductor. The leakage current of our detector was found to be ∼180 pA/cm$^2$ at 10 V/m, which was significantly reduced than that of a single a-Se detector. The x-ray sensitivity was measured as the value of 4230 pC/cm$^2$/mR at 10 V/m. We found that the parylene thin film between a CaWO$_4$ phosphor and an a-Se layer acts as an insulator to prevent charge injection from indium thin oxide (ITO) electrode into an a-Se layer under applied bias.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.271-274
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• 1999

In this paper, we studied the matrix type Powder AC Electroluminescence using ZnS:Cu,Cl Phosphor. Previously, Powder AC EL was used in Backlighting of LCD. Rescently, organic Thin Film EL was rapidly developed because of high Luminescence and low applied voltage. But Powder AC EL has Superior features that include sheet like flexibility thickness, low weight, self-emission, a wide viewing angle and a fast response time. We tried to change of phosphor thickness and binder mixture rate in order to obtain the good condition of powder AC EL and we obtained the very low breakdown voltage that was just 15V. Till now, we measured the current-voltage(V-I), luminance-voltage(V-L), Luminance-current (L-I), color coordinate (CIE), and phosphor Intensity of variable thickness. In experiment result, the devices has the luminance of 840 cd/$m^2$ and improved color coordinate, x=0.1557, y=0.2145, using a 10kHz drive frequency.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 디스플레이 광소자분야
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• pp.111-114
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• 2003

Compared to a conventional atomic layer deposition (ALD) grown Al203 film, Plasma enhanced ALD (PEALD) grown AION film was revealed to possess a large breakdown field, which is necessary for stable operation of thin film electroluminescent (TFEL) device. Also, AION is more stable than Al203 films grown by PEALD or by ALD after post-annealing process, which is inevitably required to improve luminance property of phosphor. Furthermore, AION films were applied to insulators of ZnS:Tb TFEL device. Resultant1y, they show better stability than ALD grown insulators under high electric field.

• 한국세라믹학회지
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• 제50권1호
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• pp.50-56
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• 2013

Phosphorescent materials coated with titanium dioxide were fabricated and photocatalytic reactions between these materials and VOCs gases were examined. A thin film (approx. 100 nm) of nanosized $TiO_2$ was deposited on the $Sr_4Al_{14}O_{25}$ : $Eu^{2+}$, $Dy^{3+}$, $Ag^+$ phosphor using low-pressure chemical vapor deposition (LPCVD). The characteristics of the photocatalytic reaction were examined in terms of the decomposition of benzene gas using a gas chromatography (GC) system under ultraviolet (${\lambda}$ = 365 nm) and visible light (${\lambda}$ > 420 nm) irradiation. $TiO_2$-coated $Sr_4Al_{14}O_{25}$ : $Eu^{2+}$, $Dy^{3+}$, $Ag^+$ phosphor showed different photocatalytic behavior compared with pure $TiO_2$. $TiO_2$-coated phosphorescent materials showed a much faster photocatalytic decomposition of benzene gas under visible irradiation compared to the pure $TiO_2$ for which the result was practically negligible. This suggests that the extension of the absorption wavelength to visible light occurred through energy band bending by a heterojunction at the interface of the $Sr_4Al_{14}O_{25}-TiO_2$ composite. Also, the $Sr_4Al_{14}O_{25}-TiO_2$ composite showed the photocatalytic decomposition of benzene in darkness due to the photon light emitted from the $Sr_4Al_{14}O_{25}$ phosphors.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1062-1065
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• 2004

The importance of display is becoming increasingly important due to the development of information and industry where it leads to diverse and abundant information in today's society. The demand and application range for FPD(Flat Panel Display), specifically represented by LCD(Liquid Crystal Display) and PDP(Plasma Display Panel), have been rapidly growing for its outstanding performance and convenience amongst many other forms of display. The current focus has been on OLED(Organic Light Emitting Diode) in the mobile form, which has just entered into mass production amid the different types of FPD. Many studies are being conducted in regards to device, vacuum evaporation, encapsulation, and drive circuits with the development of device as a matter of the utmost concern. This study develops a new type of light-emitting materials by synthesizing medical polymer organic chitosan and phosphor material CuS. Chitosan itself satisfies the Pool-Frenkel Effect, an I-V specific curve, with a thin film under $20{mu}m$, and demonstrates production possibility for a living body sensors solely with the thin film. Furthermore, it enables production possibility for EML of organic EL device(Emitting Layer) with liquid Green light emitting and Blue light emitting as a result of synthesis with phosphor material.

• 한국광학회:학술대회논문집
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• 한국광학회 2003년도 하계학술발표회
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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)