• 제목/요약/키워드: LB

검색결과 1,396건 처리시간 0.028초

Polyimide LB막내의 탄성 및 비탄성 tunneling 전기전도특성 (Elastic and inelastic electron tunneling characteristics in polyimide LB films)

  • 김태성;김현종
    • E2M - 전기 전자와 첨단 소재
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    • 제7권6호
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    • pp.473-480
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    • 1994
  • The electron tunnel effect in polvimide LB films sandwiched between metal electrodes has been investigated in the present work by a study of both the elastic and inelastic tunneling components. By the results of elastic tunneling experiments in Au/Pl/Au tunneling junction, we can judge the height and thickness of tunnel barrier. The inelastic current in Inelastic Electron Tunneling Spectroscopy(IETS) is due to the interaction of the tunneling electron with the vibrational modes of the molecular species in the barrier. Measurements are done on Au/PI/Pb tunneling junctions. The spectra obtained are the second derivatives of the current-voltage characteristics of these junctions : specifically, d$^{2}$1/dV$^{2}$ as a function of voltage V. Because the energies measured by IETS can be directly compared to those measured by infrared and Raman spectroscopy, IR-RAS spectroscopy also measured for reference.

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유비쿼터스 컴퓨팅 환경에서 LBS를 위한 이동 객체 관리 아키텍처 (A Moving Object Management Architecture for LBS in the Ubiquitous Computing Environment)

  • 김동오;홍동숙;박치민;한기준
    • 한국공간정보시스템학회:학술대회논문집
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    • 한국공간정보시스템학회 2005년도 GIS/RS 공동 춘계학술대회
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    • pp.29-35
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    • 2005
  • 최근 이동 객체의 위치 데이타를 활용한 위치 찾기 서비스, 교통 정보 서비스, 모바일 광고 서비스와 같은 LBS가 활성화되고 있다. 그러나, 유비쿼터스 컴퓨팅 환경이 발전함에 따라 위치를 비롯한 다양한 데이타를 획득하기 위한 센서의 종류가 다양해지고, 획득하는 데이타가 많아졌다. 이로 인해 기존에 제시된 특정 위치 인식 시스템만을 고려한 이동 객체관리 시스템을 활용할 경우 유비쿼터스 컴퓨팅 환경에서 효율적으로 LBS를 지원하기가 쉽지 않다. 따라서, 본 논문에서는 유비쿼터스 컴퓨팅 환경에서 이동 객체의 특성을 살펴보고, 유비쿼터스 컴퓨팅 환경에서의 데이타 관리 기법을 연구하였다. 그리고, 유비쿼터스 컴퓨팅 환경에서 LBS를 위해 대용량으로 발생하는 이동 객체의 위치 데이타는 물론 다양한 센서의 데이타를 효율적으로 관리할 수 있는 이동 객체 관리 아키텍처를 제시하였다. 마지막으로, 본 논문에서 제시한 유비쿼터스 컴퓨팅 환경에서 LBS를 위한 이동 객체 관리 아키텍처의 활용에 대해 살펴본다.

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UV 조사에 의한 메로시아닌 색소 LB박막의 J-aggregation 특성 (J-aggregation Property of Merocyanine Dye LB Thin Film by UV Irradiation)

  • 양창헌;이지윤;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 춘계학술대회 논문집 센서 박막재료연구회 및 광주 전남지부
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    • pp.123-124
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    • 2008
  • We investigate characteristics of J-aggregation as take advantage of LB technic. In order to confirm the applications possible for the molecular electronic device, the morphological properties of merocyanine dye were investigated by AFM. $\pi$-A curves investigated the surface pressure of the LB film from a liquid to a solid state ranged between 90 and 100 mN/m. We observed aggregation and it's characteristics by using visible reflection spectroscopy. This paper focuses on results obtained in mercocyanide dye. When LB films of merocyanine dye are mixed with arachidic acid, J-aggregate formation is exhibited. J-aggregate formation has been serving as typical systems in revealing the physical and structural aspects of nano-sized molecular aggregates constructed as muiltilayers.

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DLPC LB박막의 전기특성에 관한 연구 (A Study on the Electrical Properties of DLPC LB films)

  • 조수영;이경섭;오재한;이우선;최충석
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 추계학술대회 논문집
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    • pp.97-100
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    • 1998
  • We studied on the ultra thin L-${\alpha}$-DLPC by LB method. The $\pi$-A isotherm of the L-${\alpha}$-DLPC was measured at the air-water interface varying with the compressing speed and amounts of solutions for spreading. The molecular arrangement of deposited films were evaluated by measuring the absorption with the UVspectrometer. And we made structures of metal(Au)/L-${\alpha}$-DLPC/Metal(Au) and examined electron through L-${\alpha}$-DLPC LB films by means of current-voltage(I-V) measurement.

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고분자감응성 LB막의 유변학적인 특성을 이용한 가스센서 연구 (The Study of Gas Sensor Using Rheological Properties of Polymeric Sensitive LB Films)

  • 강현욱;김정명;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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    • pp.198-201
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    • 1997
  • The new system for identification of organic vapours and analysis method of mechanism between organic vapours and sensitive materials were attempted using the resonant resistance and resonant frequency of Quartz Crystal Analyzer (Q. C. A.). The resonant resistance shift means rheological changes in sensitive LB films occurred by the adsorption of organic vapours, while the resonant frequency shift represent the mass of organic vapour loaded in or on the sensitive LB films. It is thought that we can obtain more accurate response mechanism of organic vapour using the resonant frequency and resonant resistance diagram. The polymeric sensitive material were quantitively depositied using the LB method. In the experimental results, the adsorption behavior of organic vapour response can be decided by two type ; surface adsorption and penetration into sensitive material. Organic vapours had different positions in the Frequency-Resistance (F-R) diagram as to the kinds and concentrations of organic vapours. Thus F-R diagram can be applied to the development of one channel gas sensing system using the Quartz Crystal Analyzer.

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ITO전극위의 Hetero형 폴리피리딘Ru착체 LB막의 표면측정과 전기화학적 감광특성 (Photoelectrochemical and Microscopic Studies in Hetero Type LB Films of Polypyridine Ru Complexes on ITO Electrodes)

  • 최인희;박수길;임기조;이주성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
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    • pp.240-243
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    • 1995
  • The basic electrochemical and photochemical behavior of ultrathin mono- and hetero-type LB film of amphiphilic Ru bipyridine complex adsorbed on ITO electrode by the Langmuir- Blodgett(LB) method as monolayer and alternating multilayer state. With theoretical equation of cyclic voltammetry for redox species, the cyclic voltammogram were simulated successfully taking account the interaction parameters. We could fit almost all measured voltammograms with k$^{\circ}$=72s$\^$-1/, ${\alpha}$$\sub$a/=0.44, ${\alpha}$$\sub$c/=0.54, $\Gamma$$\sub$T/=1.4${\times}$10$\^$-10/, k=0.015s$\^$-1/ values. The AFM images of mono and hetero type LB film surfaces on ITO were also studied.

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포화지방산계 LB막의 수평방향에 대한 전기적 특성 비교 (A Comparison to Electrical properties of Fatty Acid System LB Films in Horizontal Direction)

  • 김도균;최용성;장정수;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1997년도 춘계학술대회 논문집
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    • pp.194-197
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    • 1997
  • The LB technique is one of the most powerful fabricating methods of organic ultra-thin film, which deposits a monolayer films in molecular level on the surface of the substrate. We have investigated the electrical characteristics of Myristic acid, Stearic acid and Arachidic acid LB films for horizontal direction to develop for the gas sensor. The optimum conditions for a film deposition were obtained by measurement of $\pi$-A isotherm. The status of the deposited film was confirmed by measurement of UV absorbance. We could distingished the difference of I-V characteristics for the fatty acid for the horizontal direction. The conductivity of fatty acid LB films for horizontal direction was 10$^{-7}$ ~ 10$^{-9}$ [S/cm] that mean like semiconductor.

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Flavin-Viologen 복합 LB막으로 구성된 분자광다이오드에서의 광유도 전자전달 (Photoinduced Electron Transfer in Molecular Photodiode Consisted of Flavin-Viologen Hetero-LB Films)

  • 김민진;최정우;정성욱;오세용;이원흥;신동명
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1995년도 추계학술대회 논문집
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    • pp.281-284
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    • 1995
  • A molecular photodiode was fabricated with hetero-Langmuir-Blodgett (LB) film consisting of an electron accepter(A) and sensitizer. N-Allyl-N-[3-propylamido-N\",N\"-야(n-octadecyl)]-4,4-bipyridum Dibromide and 7,8-dimethyl-10-dodecyl isoalloxan-zine were used as A and S units, respectively. By aligning hefter-LB film of A/S units on ITO glass with an aluminium thin film, a molecular photodiode with the structure of Metal/Insulator/Metal(MIM) was constructed. Due to excitation by irradiation with a 460nm monochromatic light source, the photo-induced unidirectional flow of electrons in the MIM device could be achieved and was detected as photocurrents. The direction of energy flow was in accordance with the energy level profile across the LB films. The photo switching function was achieved and the rectifying characteristics was obserbed in the molecular devise.

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LB-DECK를 이용한 철근콘크리트바닥판의 펀칭전단강도 (Punching Shear Strength of Reinforced Concrete Bridge Decks with LB-DECK)

  • 윤석구;이재홍;조선규;정재동;원용석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.390-393
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    • 2006
  • LB-DECK is used for both of permanent formwork and structural component with cast-in place concrete of concrete bridge decks. Current Korean design code recommends that concrete bridge deck with precast concrete panels have to be designed only using conventional flexural design method and does not allow the empirical design method which is based on punching shear strength of bridge deck. This paper present experimental test results of punching shear strength of concrete bridge decks with LB-DECKs. Six full-scaled concrete bridge decks, which are designed with the empirical design method, are fabricated with variation of girder spacings. Test results are presented in the paper and compared with the code predictions of ACI 318, CEB-FIP MC90. Based on the test results, it is proposed that LB-DECK is suitable to apply the empirical design method for concrete bridge decks.

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말레에이트계 공중합체 L8막의 전기적 특성 (Electrical Characteristics of Maleate Copolymer LB Films)

  • 유승엽;정상범;박재철;권영수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 C
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    • pp.1562-1564
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    • 1996
  • Langmuir-Blodgett (LB) method have been used by many rescarcher because of its facility to control the thickness of film as molecular order and orientation of molecular. We fabricated MIM device using copolymer LB films of $2C_{18}MA-VE_2$ and elecctrical conduction mechanism in ultra-thin LB film were investigated. In our experimental results, the maleate copolymer LB film have the properity of insulator like organic ultra-thin fiim. Its diclcctric constant was about 3.5 and its voltage generation about 0.1 Volt. And Schottky current was apeared as electrical conduction current and Schottky barrier was about 0.9(eV).

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