• 제목/요약/키워드: Dielectric Coating

검색결과 273건 처리시간 0.031초

유전가열물질을 코팅한 활성탄소섬유의 휘발성 유기화합물 흡착 및 마이크로파 인가에 의한 탈착 연구 (A Study on Adsorption of Volatile Organic Compound by Activated Carbon Fiber Coated with Dielectric Heating Element and Desorption by Applying Microwave)

  • 김상국;장예림
    • 한국대기환경학회지
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    • 제25권2호
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    • pp.122-132
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    • 2009
  • Adsorption of toluene by activated carbon fiber (ACF) coated with dielectric heating element and desorption by applying microwave were investigated. In order to prepare adsorbent so that VOC can be desorbed by microwave heating, fine dielectric heating element with nano size was coated on the surface of the ACF using hybrid binder. Eight adsorbents (ACF-DHE, Activated Carbon Fiber coated with Dielectric Heating Element) were prepared with different amount of dielectric heating element, kinds of hybrid binder, and solvent. In order to investigate adsorption characteristics, BET surface area, pore volume, and average pore size were measured for each adsorbent including ACF. Breakthrough experiments with toluene concentration, flow rate, bed length using fixed bed reactor were performed to investigate adsorbality of adsorbent, and results were compared with that of the ACF. Desorption reactor was constructed with modified microwave oven to investigate heating effect on ACF-DHE by applying microwave power. Each adsorbent saturated with toluene were put into desorption reactor. Composition of desorbed gas generated by applying controlled microwave power to reactor was measured. Up to now, hot air desorption method has been used. Experimental results showed that desorption method with new adsorbent prepared by coating dielectric heating element on ACF can be used for industrial application.

유전박막이 도포된 나노원뿔 패턴된 단결정 Si 기판의 광특성 (Optical Characteristics of Nanocone-patterned c-Si Wafers Coated with Dielectric Thin Films)

  • 김은아;박지민;고은지;김동욱
    • Current Photovoltaic Research
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    • 제5권2호
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    • pp.55-58
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    • 2017
  • We investigated the influences of dielectric thin film coating on the optical characteristics of c-Si wafers with nanocone (NC) arrays using finite-difference time-domain (FDTD) simulations. Dielectric thin films on high-refractive-index surface can lower optical reflection and reflection dips appear at the wavelengths where destructive interference occurs. The optical reflection of the NC arrays was lower than that of the dielectric-coated planar wafer in broad wavelength range. Remarkable antireflection effects of the NC array could be attributed to beneficial roles of the NCs, including the graded refractive index, multiple reflection, diffraction, and Mie resonance. Dielectric thin films modified the optical reflection spectra of the NC arrays, which could not be explained by the interference alone. The optical properties of the dielectric-coated NC arrays were determined by the inherent optical characteristics of the NC arrays.

솔-젤법에 의한 강유전성 PFN 박막의 제조 및 특성평가 (Fabrication and Characterization of Ferroelectric PFN Thin Film by Sol-Gel Processing)

  • 류재율;김병호;임대순
    • 한국세라믹학회지
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    • 제33권6호
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    • pp.665-671
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    • 1996
  • Ferroelectric Pb(Fe1/2Nb1/2)O3 thin films were successfully fabricated on ITO/Glass substrate by sol-gel proces-sing and characterized to determine the dielectric and electric properties. Viscosity of PEN sol measured to investigate rheological properties was 3.25 cP which was proper for coating. The sol also showed Newtonian behavior. RTA(Rapid Thermal Annealing) was used for the annealing of the thin film and 1200~1700$\AA$ thick PEN thin films were fabricated by repeating the intermediate and the final annealing. After the deposition of Pt as top electrode by vacuum evaporation dielectric and electric properties were measured. Dielectric properties of FFN thin film were enhanced by increasing the perovskite phase fraction with increasing the annealing temperature. Measured dielectric constant of 1700$\AA$ PFN thin film annealed at $650^{\circ}C$ was 890 at 1kHz Capacitatnce density and dielectric loss were 47 fF/${\mu}{\textrm}{m}$2 and 0.47 respectively. As a result of measuring Curie temperature PFN thin films had Curie point with a rang of 110~12$0^{\circ}C$ and showed broad dielectric peak at that point. Leakage current of the PFN thin films were increased with increasing the annealing tempera-ture.

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유전체가 다층으로 코팅된 평행 2선식 전송선로 해석 (Analysis of a Parallel-Two-Wire Transmission Line Coated with Multi-layer Dielectric Material)

  • 천동완;김원기;신철재
    • 대한전자공학회논문지TC
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    • 제41권12호
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    • pp.131-137
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    • 2004
  • 본 논문에서는 등각사상 법을 이용해 유전체가 다층으로 코팅된 평행 2선식 전송선로의 특성임피던스 및 유효 유전상수 등을 계산하는 방법을 제안하였다. 먼저 두께 및 유전상수가 다른 유전체가 임의의 N 층으로 코팅되었을 때 평행 2선식 전송선로의 정전용량을 계산하였으며, 이를 이용해 임피던스 및 유효 유전상수 등을 계산하였다. Ansoft 사의 Maxwell 2D를 이용한 시뮬레이션 결과와 비교하였을 때, 계산 결과가 오차범위 4% 이내로 거의 일치함을 알 수 있었다.

다층 및 불균일 SiON 박막을 이용한 광간섭필터의 설계 및 제작 (Design and Fabrication Optical Interference Filters using Multiple and Inhomogeneous Dielectric Layers)

  • Lim, Sung kyoo
    • 전자공학회논문지A
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    • 제32A권11호
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    • pp.44-51
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    • 1995
  • Homogeneous, compositionally graded, and superlattice-like silicon oxynitride(SiON) dielectric layers, with the refractive index varying from 1.46 to 2.05 as a function of film thickness, were grown by computer-controlled plasma-enhanced chemical vapor deposition (PECVD) using silane, nitrogen, and nitrous oxide reactant gases. An antireflection(AR) coating and thin-film electroluminescent(TFEL) devices with multiple dielectrics were designed and fabricated using real time control of reactant gases of the PECVD system.

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PMD(Pre-Metal Dielectric) 선형 질화막 공정의 최적화에 대한 연구 (Optimization of PMD(Pre-Metal Dielectric) Linear Nitride Precess)

  • 정소영;김상용;서용진
    • 한국전기전자재료학회논문지
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    • 제14권10호
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    • pp.779-784
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    • 2001
  • In this work, we studied the characteristics of nitride films for the optimization of PMD(pro-metal dielectric) linear process, which can be applied to the recent semiconductor manufacturing process. We split the deposit condition of nitride films into four parts such as PO(protect overcoat) nitride, baseline, low hydrogen and high stress and low hydrogen, respectively. We tried to find out correlation between BPSG deposition and densification. In order to analyze the changes of Si-H and Si-NH-Si bonding density, we used FTIR area method. We also investigated the crack generation on wafer edge after BPSG densification, and the changes of nitride film stress as a function of RF power variation to judge whether the deposited films.

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졸-겔법에 의한 $Nb_2O_5$ 유전박막의 형성 및 박막의 결정상과 유전특성의 분석 (Formation of $Nb_2O_5$ Thin Films by Sol-Gel Technique and Analysis of Their Crystalline Phases and Dielectric Characteristics)

  • 조남희;강희복;이전국;김윤호
    • 한국세라믹학회지
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    • 제30권1호
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    • pp.17-24
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    • 1993
  • Sol-gel spin-coating technique was used to produce Nb2O5 thin films on silicon substrates from Nb(OC2H5)5 precursor. The films were heat-treated at temperatures between $600^{\circ}C$ and 100$0^{\circ}C$ in oxygen atmosphere and their crystalline phases, chemical states, and dielectric characteristics were investigated by X-ray diffractometry (XRD), Auger electron spectroscopy (AES), and C-V measurements, respectively. After 1 hour heat-treatment at 80$0^{\circ}C$, T-type Nb2O5 was formed, and its chemical composition was homogeneous with no appreciable SiO2 oxide at interfaces between the films and substrates. The films heat-treated at temperatures between $600^{\circ}C$ and 80$0^{\circ}C$ exhibit dielectric constant of less than 20 while the films heat treated at 100$0^{\circ}C$ show dielectric constant of 28.

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Characterization of Ceramic Oxide Layer Produced on Commercial Al Alloy by Plasma Electrolytic Oxidation in Various KOH Concentrations

  • Lee, Jung-Hyung;Kim, Seong-Jong
    • 한국표면공학회지
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    • 제49권2호
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    • pp.119-124
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    • 2016
  • Plasma electrolytic oxidation (PEO) is a promising coating process to produce ceramic oxide on valve metals such as Al, Mg and Ti. The PEO coating is carried out with a dilute alkaline electrolyte solution using a similar technique to conventional anodizing. The coating process involves multiple process parameters which can influence the surface properties of the resultant coating, including power mode, electrolyte solution, substrate, and process time. In this study, ceramic oxide coatings were prepared on commercial Al alloy in electrolytes with different KOH concentrations (0.5 ~ 4 g/L) by plasma electrolytic oxidation. Microstructural and electrochemical characterization were conducted to investigate the effects of electrolyte concentration on the microstructure and electrochemical characteristics of PEO coating. It was revealed that KOH concentration exert a great influence not only on voltage-time responses during PEO process but also on surface morphology of the coating. In the voltage-time response, the dielectric breakdown voltage tended to decrease with increasing KOH concentration, possibly due to difference in solution conductivity. The surface morphology was pancake-like with lower KOH concentration, while a mixed form of reticulate and pancake structures was observed for higher KOH concentration. The KOH concentration was found to have little effect on the electrochemical characteristics of coating, although PEO treatment improved the corrosion resistance of the substrate material significantly.

Zirconium Titanate Thin FIlm Prepared by Surface Sol-Gel Process and Effects of Thickness on Dielectric Property

  • Kim, Chy-Hyung;Lee, Moon-Hee
    • Bulletin of the Korean Chemical Society
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    • 제23권5호
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    • pp.741-744
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    • 2002
  • Single phase of multicomponent oxide ZrTiO4 film could be prepared through surface sol-gel route simply by coating the mixture of 100 mM zirconium butoxide and titanium butoxide on $Pt/Ti/SiO_2Si(100)$ substrate, following pyro lysis at $450^{\circ}C$, and annealing it at 770 $^{\circ}C.$ The dielectric constant of the film was reduced as the film thickness decreased due to of the interfacial effects caused by layer/electrode and a few voids inside the multilayer. However, the dielectric property was independent of applied dc bias sweeps voltage (-2 to +2 V).The dielectric constant of bulk film, 31.9, estimated using series-connected capacitor model was independent of film thickness and frequency in the measurement range, but theoretical interfacial thickness, ti, was dependent on the frequency. It reached a saturated ti value, $6.9{\AA}$, at high frequency by extraction of some capacitance component formed at low frequency range. The dielectric constant of bulk ZrTiO4 pellet-shaped material was 33.7 and very stable with frequency promising as good applicable devices.

$BaTiO_3/SrTiO_3$ 이종층 박막/후막의 유전특성 ($BaTiO_3/SrTiO_3$ Heterolayered Thin/Thick films Dielectric Properties)

  • 한상욱;김지헌;박인길;이성갑;이영희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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    • pp.1850-1852
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    • 2005
  • $SrTiO_3$ and $BaTiO_3$ sol-liquids and powders were prepared by the sol-gel method. $SrTiO_3/BaTiO_3$ heterolayered thin/thick films have been prepared on the $Al_2O_3$ substrates by screen printing and spin-coating method. The thin films were sintered at $750^{\circ}C$ in the air for 1 hour and the thick films sintered at $1325^{\circ}C$ in the air for 2 hours, respectively. The $SrTiO_3/BaTiO_3$ thin/thick films's structural and dielectric properties were investigated. Increasing the spin-coating times, (110), (200), (211) peaks of the $SrTiO_3$ were increased. The X-ray diffraction(XRD) patterns and SEM photographs indicated that the $SrTiO_3$ phase were formed in the surface of $BaTiO_3$ thick films. The average thickness of a $BaTiO_3$ thick films and $SrTiO_3$ thin films were $50{\mu}m$ and 400nm, respectively The dielectric constant and dielectric loss of the $SrTiO_3/BaTiO_3$ thin/thick films with $SrTiO_3$ coated 5 times were 1598 and 0.0436 at 10KHz.

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