• 제목/요약/키워드: LB films

검색결과 391건 처리시간 0.022초

메틸렌기의 길이에 따른 LB막의 유전 특성 비교 (Comparison to Dielectric Properties of LB Films for Length of Methylene Group)

  • 강기호;김도균;최용성;장정수;권영수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 D
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    • pp.1843-1845
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    • 1999
  • We have investigated the dielectric characteristics of palmitic acid(PA), stearic acid (SA) and arachidic acid(AA) Langmuir-Blodgett(LB) films because these fatty acid systems have a same hydrophilic group and a different hydrophobic one (alkyl chain length). In this work. fatty acid systems were used as LB films and the status of the deposited films was confirmed by evaluating the transfer ratio. the UV absorption and the capacitance. Also, the dielectric characteristics such as the frequency-capacitance characteristics and the dielectric dispersion and absorption characteristics of PA, SA and AA through-plane were measured. The relative dielectric constants of PA, SA and AA LB films were about $2.6\sim4.6$, $2.4\sim4.1$ and $2.2\sim3.8$, respectively. That is, the relative dielectric constants were decreased in proportion to the chain length of methylene group. And, the dielectric dispersion and absorption of each fatty acid LB films have arisen from spontaneous polarization of dipole polarization in the range of $10^4\sim10^5[Hz]$.

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공중합체 LB막의 제작과 유기가스 반응 특성 (Fabrication and organic gas response characteristics of the copolymer LB films)

  • 신훈규;최용성;장정수;권영수
    • E2M - 전기 전자와 첨단 소재
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    • 제9권2호
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    • pp.180-187
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    • 1996
  • The use of preformed copolymers and their cross-linking have been attempted in order to improve the intrinsic fragility of monolayers and Langmuir-Blodgett (LB) films and to make their technological applications. It has shown that an imidization followed a polyion-complexation can stabilize the LB films against heat and solvents. And, when the polymer structure was properly designed, concurrent removal of the alkyl tails together with imide formation could be accomplished. In this paper, the monolayers of the polymers which were polyion-complexed with PAA at the air-water interface can be transferred onto solid substrates such as porous fluorocarbon membranes filter and quartz crystal microbalance. The properties of the monolayers and the LB films will be discussed by .pi.-A isotherms, FT-IR, DSC, deposition ratio, QCM, and SEM. In addition, it was attempted to investigate the response characteristics of polymer LB films to the organic gases by the use of QCM.

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금속이온 착체에 의한 G4-48PyP 덴드리머 LB막의 전기적 특성 (Electrical Properties of G4-48PyP Dendrimer LB Films complex with Metal Ions)

  • 정상범;유승엽;박재철;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.769-772
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    • 2002
  • Dendrimers are well-defined macromolecules exhibiting a tree-like structure, first derived by the cascade molecule approach. Peculiar features of the dendritic geometry are the large number of end groups as well as the shape persistence in higher generations, approaching spherical geometry. And one of the most peculiar characteristics of dendritic macromolecules is their controlled molecular structure and orientation, which means that they have a practical application in achieving a highly organized molecular arrangement. We attempted to fabricate a dendrimer LB films containing 48 pyridinepropanol functional end group. As the pyridinepropanol functional group could form a complex structure with metal ions. We investigated the surface activity of dendrimer films at air-water interface compared with pure dendrimer and its complex with $Fe^{2+}$ ions into subphase. We though that metal ions are contributed to networking or branching reaction between dendrimers. And we expected that it can result in the differences on the electrical properties. We have studied the electrical properties of the ultra thin dendrimer LB films investigated by the current-voltage characteristics of metal dendrimer LB films/metal (MIM) structure.

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Stearic acid와 PDA LB막의 특성 분석과 막 형성 조건에 관한 연구 (A study on the characterization of stearic acid and PDA LB films and the optimum conditions for the stable films on the water)

  • 전용주;권오대;정상돈;정철형;김장주
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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    • pp.102-104
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    • 1989
  • The characteristics of stearic acid and PDA (pentacosaDiyonicAcid) LB films were studied using the XRD spectra for regularity of layers and ellipsometer for the total thickness of multilayer films. From the experiments of varying the PH and temperature, it was found that the stability of monolayer on the water subphase was very sensitive to its PH and temperature. The optimum condition of PH for the stable stearic acid LB film was 6$\sim$6.5. The PDA LB films were stable at the lower temperature than room temperature: we obtained very uniform PDA LB films at 12$^{\circ}C$.

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Functional Polymer Thin Films based on the Layer-by-Layer Deposition

  • Char, Kook-Heon
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.192-192
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    • 2006
  • Organic/organic and organic/inorganic multilayer films composed of organic polyelectrolytes (PE) and inorganic nanoparticles/platelets were prepared from the layer-by-layer (LbL) deposition using both spinning and dipping. The difference in both LbL methods is quantitatively compared in terms of internal layer ordering and physical properties of the multilayered films. Additionally, we suggest that the patterned multilayer films can be easily prepared by the combination of the spin SA and the lift-off method. Freestanding films were also prepared with the LbL deposition on low energy substrates, which allows the detailed analysis of composition within the films. Other LbL thin films prepared with block copolymer micelles will be discussed.

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LB법으로 제작된 octadecylviologen-$(TCNQ^-)_2$ 박막의 전자기적 특성 연구 (A study on the electromagnetic characteristics of the octadecylviologen-$(TCNQ^-)_2$ thin films with The Langmuir-Blodgett technique)

  • 신동명;박제상;;강도열
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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    • pp.423-426
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    • 1995
  • Langmuir-Blodgett technique offers a convenient and elegant way to organic conducting systems for ultra thin films. In conducting systems based on LB films, TCNQ derivatives have been extensively studied as electron acceptor molecules in a large number of organic conducting systems.[1] A very interesting UV-visible spectra of octadecylviologen-$(TCNQ^-)_2$ was obtained from a methylenechloride and acetonitrile mixture, and from Langmuir-Blodgett films. The ESR characteristics of octadecylviologen-$(TCNQ^-)_2$ were studied to understand conducting mechanism and structure of LB films. The ESR spectra infer that the N-dococylquinolinium-TCNQ LB films has anisotropic property. But octadecylviologen-$(TCNQ^-)_2$ does not show angular dependence. As the temperature increases from 350K to 450K, the ESR signal of LB films becomes sharp. Scanning calorimetry(DSC) of octadecylviologen-$(TCNQ^-)_2$ provides the endothermic reaction temperature of the films, 340K, which corresponds to the temperature, 365K, of the new ESR signal.

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LB 초박막의 기전력 발생 (The Electro-Motive Force Generation in LB Insulating Films)

  • 권영수;강도열;국상훈
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1993년도 춘계학술대회 논문집
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    • pp.126-128
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    • 1993
  • It is well known that D.C voltage is generated at the element of MIM structure which is sandwiched between two electrode of Langmuir-Blodgett(LB) ultra-thin films. In this paper, the experiments are processed for the sample which is leaved at the atomosphere since it is fabricated in 1986. we measureed the same voltage as the time of fabricating in LB films.

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LB막이 누적된 QCM의 저항 및 주파수 특성해석 (Resistance and Frequency Properties Analysis of QCM Coated with LB Films)

  • 강현욱;진철남;김정명;권명수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 추계학술대회 논문집
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    • pp.465-467
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    • 1997
  • The oscillating properties of quartz Crystal Microbalance(QCM) were analyzed by electrical measurement. We tried to analyze the properties of quartz crystal coated with Langmuir-Bladgett(LB) films using the frequency and resistance at resonance in the electrical equivalent circuit. The resonant frequency was decreased linearly as to layers of LB films, however, there are some gap between theoretical values, Sauerbrey's equation and experimental values. The resistance was increase nonlinearly as to layers.

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PECCP LB 박막을 이용한 유기 발광 타이모드의 제작과 이의 특성 (Fabrication and Properties of OLEDs using PECCP Langmuir-Blodgett(LB) Films)

  • Lee, Ho-Sik;Lee, Won-Jae;Park, Myung-Gyu;Songe, Min-Jeng;Park, Jong-Wook
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.831-834
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    • 2000
  • Characteristics of organic light-emitting diodes(OLEDs) were studied with devices made by PECCP[poly(3,6-N-2-ethylhexyl carbazolyl cyanoterephthalidene)] Langmuir-Blodget(LB) films. The emissive organic material was synthesized and named PECCP, which has a strong electron donor group and an electron accepter group in main chain repeated unit. The LB technique was employed to investigate the identification of the recombination zone in the ITO/PECCP LB films/Alq$_3$/Al structure by varying the LB film thickness. PECCP was considered as an emissive layer and Alq$_3$was used as an electron-transport layer. We measured current-voltage(I-V) characteristics, UV/visible absorption, PL spectrum, and EL spectrum of those devises.

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Octa-dodecyloxy Copper- phthalocyanine LB 막의 $NO_2$가스 탐지 특성과 전기 전도도에 관한 연구 (A Study on the $NO_2$ Gas Detection Characteristics and Electrical Conductivity of the Octa-dodecyloxy Copper-phthalocyanine LB Films)

  • 구자룡;김영관;김정수
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권2호
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    • pp.80-85
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    • 1999
  • In this paper, $NO_2$ gas detection characteristics of Octa-dodecyloxy copper-phthalocyanine films prepared by LB method was investigated measuring the electrical conductance of these films. The electivity characteristics of these LB films exposed to $NO_2, NO, and SO_2$ gas was also investigated. Conductivity activation energy of these films as a function of temperature was obtained.

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