• 제목, 요약, 키워드: Dielectric material

검색결과 2,569건 처리시간 0.043초

Dependence of Ozone Generation in a Micro Dielectric Barrier Discharge on Dielectric Material and Micro Gap Length

  • Sakoda, Tatsuya;Sung, Youl-Moon
    • KIEE International Transactions on Electrophysics and Applications
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    • v.4C no.5
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    • pp.201-206
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    • 2004
  • In order to investigate the optimum conditions for the effective ozone formation in a dielectric barrier discharge, measurements of ozone concentration were carried out for various conditions such as the gap length, the dielectric material and the operating gas. It was found that the optimum discharge conditions differed exceedingly in the types of operating gases and dielectric materials. In dry air, dielectric material with low dielectric constant and thermal conductivity, which might contribute to the restriction of the gas temperature rise in the discharge region, proved effective in obtaining both high ozone yield and concentration. The optimum gap length was considered to be in the range of 600-800 mm. In oxygen, using a quartz glass disk as a dielectric material, the required condition to obtain the high ozone yield and concentration was expanded.

적색 유기발광소자의 휘도향상을 위한 Dielectric layer 설계 및 제작에 관한 연구 (The Study on Dielectric layer Design and Manufactor for Luminance Improvement of Red Organic Light Emitting Device)

  • 기현철;김선훈;김두근;김상기;정행윤;최용성;홍경진
    • 전기학회논문지
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    • v.59 no.5
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    • pp.918-921
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    • 2010
  • We have proposed an dielectric layer to improve the luminance of red organic light emitting device. Here, we have calculated refractive index of dielectric layer material that was revised refractive index of organic material, ITO and glass. Refractive index of dielectric layer material was 1.711. The structure of dielectric layer was designed in organic material/ITO/dielectric layer/glass. Dielectric material changed thickness that deposited by ion-assisted deposition system. Transmittances of ITO were 95.66-98.85 [%]. Red OLED was fabricated with the structure of TPD($400[{\AA}]$)/DCMII($20[{\AA}]$), Rubrene($20[{\AA}]$)/Alq3($500[{\AA}]$)/LiF($15[{\AA}]$)/Al($1,000[{\AA}]$). Turn-on voltage and Luminance of Red OLED were 10 [V] and 5,857 cd/m2.

Magneto-Dielectric Material을 이용한 소형 Composite Right/Left-Handed Transmission Line Metamaterial 안테나 (A Small Composite Right/Left-Handed Transmission Line Metamaterial Antenna Using a Magneto-Dielectric Material)

  • 장경덕;김재희;김기호;성원모;박위상
    • 한국전자파학회논문지
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    • v.19 no.2
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    • pp.223-230
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    • 2008
  • 본 논문에서는 magneto-dielectric material을 이용하여 CRLH-TL 안테나를 소형화 시키는 방법을 제안하였다. 제안된 안테나는 patch와 via를 이용하여 구현한 mushroom 구조의 CRLH-TL 안테나에 SRR을 이용한 magneto-dielectric material을 장하한 구조이다. 시뮬레이션을 통해 SRR의 동작 특성을 살펴보았고, SRR을 이용하여 기판의 투자율 값을 증가시킬 수 있음을 확인하였다. 또한, magneto-dielectric material을 이용함으로써 CRLH-TL 안테나의 공진 주파수를 감소시킬 수 있음을 확인하였다. -1차 공진 모드에서 7.13 %, 0차 공진 모드에서 23.9 %의 주파수 감소 효과를 얻을 수 있었다. 0차 공진 모드에서 동작하는 안테나를 제작하여 반사 손실과 방사 패턴을 살펴보았다. 제작된 안테나의 동작 주파수는 1.888 GHz이며, 측정된 대역폭은 0.48 %이고, 이득은 0.534 dBi, 효율은 51.7 %이다.

Numerical Method for Computing the Resonant Frequencies and Q-factor in Microwave Dielectric Resonator

  • Kim, Nam-young;Yoo, Hojoon
    • 한국전기전자재료학회:학술대회논문집
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    • pp.245-248
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    • 1997
  • The dielectric resonators(DRs) with dielectric properties are widely used in microwave integrated circuit(MICs) and monolithic microwave integrated circuits(MMICS). The variational method as numerical simulation scheme would be applied to calculate the resonant frequencies(fr) and Q-factors of microwave dielectric resonators. The dielectric resonator with a cylindrical “puck” structure of high dielectric material is modeled in this simulation. The parameters, such as the diameter, the height, and the dielectric constant of dielectric resonator, would determine the resonant frequency and the Q-factor. The relationship between these parameters would effect each other to evaluate the approximate resonant frequency. This simulation method by the variational formula is very effective to calculate fr, and Q-factor. in high frequency microwave dielectric resonator The error rate of the simulation results and the measured results would be considered to design the microwave dielectric resonators.

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액체유도체의 절연특성에 미치는 초음파의 영향 (Ultransonic Effect on the Break-Down Characteristics of Liquid Dielectrics)

  • 전춘생;김홍근;홍봉식
    • 전기의세계
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    • v.26 no.4
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    • pp.61-67
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    • 1977
  • This paper treats the Ultrasonic effects on the break down characteristics of Liquid Dielectric Material 1) Relative Dielectric constant, Es of Liquid Dielectric Material at a constant temperature decreases in proportion to the irradiated time of Ultrasonic radiation and its intensity, and reaches to a certain saturated value. The saturated value varies with the intensity of Ultrasonic radiation. 2) Power factor of Liquid Dielectric Material at a constant temperature increases in proportion tothe irradiated time of Ultrasonic radiation and its intensity, and reaches to a certain saturated value. The saturated value varies with the intensity of Ultrasonic radiation. 3) Relative resistance of Liquid Dielectric Material at a constant temperature decrease with the irradiated time of Ultrasonic radiation, but the effect of its intensity is very irregular. 4) Break-down strength of Liquid Dielectric Material, at a constant temperature decreases with the irradiated time of Ultrasonic radiation and its intensity, and then reaches to a saturated value.

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복합산화물 $(Ba Ca)TiO_3$-ZnO의 구조적 및 유전분극 특성 (The structural and dielectric polarization characteristics of composite oxide material in $(Ba Ca)TiO_3$-Zn)

  • 홍경진;임장섭;정우성;민용기;김용주;김태성
    • E2M - 전기 전자와 첨단 소재
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    • v.10 no.3
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    • pp.239-246
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    • 1997
  • The ZnO is stabilize dielectric constant over a broad temperature range because its addition makes the relaxation time short. In this study, the composite oxide material (B $a_{0.85}$ $Ca_{0.15}$)Ti $O_{3}$ was mixed by ZnO additive material and the dielectric polarization characteristics was studied. The relative density was over 90[%] at all specimen in the structural characteristics. Among of the specimen, the relative density of (B $a_{0.85}$ $Ca_{0.15}$)Ti $O_{3}$ with ZnO (0.4mol) has a 95[%]. The grain size of composite oxide material with an increasing ZnO increased and it was 1.0[.mu.m]-1.22[.mu.m]. In the electrical characteristics, the charge and discharge current was increased by ZnO addition. The dielectric relaxation time was increased by space charge polarization at above 110[.deg. C] and the dielectric relaxation time was fixed by space charge polarization of para-dielectric layer at below 110[.deg. C]. The dielectric relaxation time was maximum when the grain size was small. The dielectric relaxation time is decreased with an additive material ZnO and interface polarization, existing void at the grain and grain boundary. The remnant polarization is increased and the coercive electric field is decreased by ZnO.

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Dielectric Polymers for OTFT Application

  • Choi, Sung-Lan;Kim, Yeon-Ok;Kim, Hong-Doo
    • Journal of Information Display
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    • v.11 no.3
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    • pp.95-99
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    • 2010
  • A series of new dielectric polymers with phenyl, epoxy, and carboxylicacid functional groups was prepared via free-radical polymerization. The effect of such dielectric polymers with various functional groups on the performance of OTFT was investigated. The nonpolar groups of terpolymer made the surface of the dielectric layer more hydrophobic and improved the crystal growth of pentacene on the gate insulator, resulting in higher mobility. By controlling the functional group, the electric characteristics of OTFT performance was varied, with $0.00017-0.15\;cm^2/V{\cdot}s$ mobility.

마이크로전자 응용에서의 저유전율 고분자 재료 (Low Dielectric Constant Polymeric Materials for Microelectronics Applications)

  • 이호영
    • 마이크로전자및패키징학회지
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    • v.9 no.3
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    • pp.57-67
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    • 2002
  • 반도체 칩의 신호처리속도를 향상시키기 위한 방법에는 세 가지가 있다. 첫 번째 방법은 금속배선의 배치(layout)를 바꾸는 것이고, 두 번째 방법은 배선으로 사용되는 금속의 비저항을 감소시키는 것이며, 세 번째 방법은 절연재료(insulating material)의 유전상수(dielectric constant)를 감소시키는 것이다. 첫 번째나 두 번째의 방법에 대해서는 많은 연구가 이루어졌고, 지금도 연구가 이루어지고 있다. 그러나 첫 번째나 두 번째의 방법을 통하여 얻을 수 있는 신호처리속도의 향상보다는 세 번째 방법을 통하여 얻을 수 있는 신호처리속도의 향상이 더 크다. 본 논문에서는 먼저 마이크로전자에 응용되기 위한 절연재료의 요구조건을 살펴보고, 지금까지 개발된 저유전율 고분자재료들을 간략하게 소개할 예정이다. 아울러 유전상수를 낮추기 위하여 최근 개발된 기공을 갖는 고분자재료들과 이들을 제조하기 위한 공정에 대해서도 간략하게 소개할 예정이다.

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ITO/$Alq_3$/Al 구조 박막의 유전분산과 흡수에 관한 연구 (A Study on the Dielectric Dispersion and Absorption of ITO/$Alq_3$/Al Thin Film)

  • 오용철;김상진;성낙진
    • 한국전기전자재료학회:학술대회논문집
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    • pp.490-491
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    • 2007
  • We have investigated dielectric dispersion and absorption in organic light-emitting diodes using 8-hydroxyquinoline aluminum($Alq_3$) as an electron transport and emissive material. We analyzed the dielectric dispersion and absorption of organic light emitting diodes using impedance characteristics measurement by the auto-balancing bridge technique of ITO/$Alq_3$/Al. Impedance characteristics was measured complex impedance Z and phase e in the frequency range of 40Hz to $10^8Hz$. We obtained dielectric constant and loss tangent (tan $\delta$) of the device. From these analyses, we are able to interpret a dielectric dispersion and dielectric absorption contributed by an interfacial and orientational polarization.

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고주파 기판용 PTFE 복합체 형성 압력에 따른 유전 특성 (Dielectric Characteristics of Polytetrafluoroethylene-based Composites for Microwave Substrates with Formation Pressure)

  • 최홍제;전명표;조용수;조학래
    • 한국전기전자재료학회논문지
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    • v.26 no.6
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    • pp.429-433
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    • 2013
  • PTFE composites for use of microwave substrate were fabricated by impregnation and heat treatment fabrication with glass fabric. This study shows dielectric properties such as dielectric constant and loss can be controlled by thickness of PTFE composite with change of pressure condition in heating press process. The dielectric constant of the PTFE composites has decreasing tendency as given higher pressure condition. The dielectric loss has similar result too. Especially, the case of the dielectric loss was affected by the condition of pressure at heating press and had the best performance under 3 MPa. In order to see the reason why thickness conditions make different, their microstructures were also observed.